Central obesity, smoking habit, and hypertension are associated with lower antibody titres in response to COVID-19 mRNA vaccine

Mortality risk in patients with obesity and COVID-19 infection: a systematic review and meta-analysis

Obesity is a risk factor for severe respiratory diseases, including COVID-19 infection. Meta-analyses on mortality risk were inconsistent. We systematically searched 3 databases (Medline, Embase, CINAHL) and assessed the quality of studies using the Newcastle-Ottawa tool (CRD42020220140). We included 199 studies from US and Europe, with a mean age of participants 41.8-78.2 years, and a variable prevalence of metabolic co-morbidities of 20-80 %. Exceptionally, one third of the studies had a low prevalence of obesity of <20 %. Compared to patients with normal weight, those with obesity had a 34 % relative increase in the odds of mortality (p-value 0.002), with a dose-dependent relationship. Subgroup analyses showed an interaction with the country income. There was a high heterogeneity in the results, explained by clinical and methodologic variability across studies. We identified one trial only comparing mortality rate in vaccinated compared to unvaccinated patients with obesity; there was a trend for a lower mortality in the former group. Mortality risk in COVID-19 infection increases in parallel to an increase in BMI. BMI should be included in the predictive models and stratification scores used when considering mortality as an outcome in patients with COVID-19 infections. Furthermore, patients with obesity might need to be prioritized for COVID-19 vaccination.

Side effects of CoronaVac® COVID-19 vaccination: Investigation in North Jakarta district public health center communities in Indonesia

Background

The decreasing prevalence of COVID-19 has highlighted the value of vaccinations. CoronaVac® vaccine was one of the most widely used vaccines in Indonesia, in other Southeast Asian countries, as well as in Latin America. However, to date the safety and side effect profiles of CoronaVac® vaccine among the Indonesian population have not been reported.

Objective

In this study, the CoronaVac® safety profiles were determined in a community of a public health center in North Jakarta, Indonesia.

Method

This is a descriptive cross-sectional questionnaire-based study on vaccine side effects as recorded in the yellow form (MESO). Patients (n = 300) who received CoronaVac® vaccinations between July and August 2021 were enrolled. SPSS was used to analyze the descriptive data.

Results

Most respondents were women (72.7 %) between the ages of 17 and 21 years. A significantly (p = 0.009) positive correlation was established between the vaccine side effects (namely pain at the injection site) with the female gender. Other side effects such as fatigue (p = 0.034) and headache (p < 0.001) were also correlated with disease comorbidity.

Conclusion

Overall, the side effects following the first and the second doses were generally mild and included fever, pain in the injection area, fatigue, headache, drowsiness, diarrhea, cough, and nausea. Regarding vaccine efficacy, CoronaVac® confers better protection following the second dose administration where the percentage of respondents affected with COVID-19 (26.7 %) decreased to only 20.3 % following the second dose.

Poor immune response to inactivated COVID-19 vaccine in patients with hypertension

Purpose

The safety and efficacy of vaccination in people with hypertension (HTN) is important. There are currently a few data on the immunogenicity and safety of inactivated SARS-CoV-2 vaccinations in hypertension patients.

Methods

After receiving a two-dose immunization, 94 hypertension adult patients and 74 healthy controls (HCs) in this study, the evaluation included looking at antibodies (Abs) against receptor binding domain (RBD) IgG, SARS-CoV-2 neutralizing antibodies (NAbs), RBD-specific B cells, and memory B cells (MBCs).

Results

There was no discernible difference in the overall adverse events (AEs) over the course of 7 or 30 days between HTN patients and HCs. HTN patients had lower frequencies of RBD-specific memory B cells and the seropositivity rates and titers of Abs compared with HCs (all, p < 0.05). HTN patients with cardiovascular and cerebrovascular conditions (CCVD) have lower titers of CoV-2 NAb than in HCs. The titers of both Abs in HTN declined gradually over time.

Conclusion

Inactivated COVID-19 vaccinations were safe in hypertension patients; however humoral immune was limited, especially merged CCVD and declined gradually over time.

Short-term side effects of BNT162b2 vaccine in primary care settings in Qatar: a retrospective study

Background

Despite the established effectiveness of the BNT162b2 Vaccine, the novel technology demands careful safety monitoring. While global studies have explored its safety, local data remains limited and exhibits some variability. This study investigated short-term side effects among BNT162b2 vaccinated individuals in Qatar.

Methods

A retrospective analysis was conducted using data extracted from the electronic health records of individuals aged 18 or older across 8 primary health centers who received either the first or second dose of the BNT162b2 vaccine during the period from December 23, 2020, to April 24, 2021. The proportions of individuals experiencing short-term side effects after each dose were calculated. Logistic regression and log binomial regression analyses were used to explore associations with the side effects.

Results

Among 7,764 participants, 5,489 received the first dose and 2,275 the second, with similar demographics between the groups. After the first dose, 5.5% reported at least one local side effect, compared to 3.9% after the second, with a 1.4 times higher incidence after the first dose (RR 1.4, 95% CI 1.14-1.75) compared to the second. Systemic side effects after the second dose were 2.6 times more common than after the first (RR 2.6, 95% CI 2.15-3.14). Gender, nationality, history of prior COVID-19 infection, and obesity were significantly associated with side effects after the first dose, while age, gender, and nationality, were significant factors after the second dose.

Conclusion

The rates of side effects following the BNT162b2 vaccine in Qatar were relatively low, with age, gender, nationality, previous infection, and obesity identified as significant predictors. These results emphasize the need for tailored vaccination strategies and contributes valuable insights for evidence-based decision-making in ongoing and future vaccination campaigns.

Determinants of health as predictors for differential antibody responses following SARS-CoV-2 primary and booster vaccination in an at-risk, longitudinal cohort

Post vaccine immunity following COVID-19 mRNA vaccination may be driven by extrinsic, or controllable and intrinsic, or inherent health factors. Thus, we investigated the effects of extrinsic and intrinsic on the peak antibody response following COVID-19 primary vaccination and on the trajectory of peak antibody magnitude and durability over time. Participants in a longitudinal cohort attended visits every 3 months for up to 2 years following enrollment. At baseline, participants provided information on their demographics, recreational behaviors, and comorbid health conditions which guided our model selection process. Blood samples were collected for serum processing and spike antibody testing at each visit. Cross-sectional and longitudinal models (linear-mixed effects models) were generated to assess the relationship between selected intrinsic and extrinsic health factors on peak antibody following vaccination and to determine the influence of these predictors on antibody over time. Following cross-sectional analysis, we observed higher peak antibody titers after primary vaccination in females, those who reported recreational drug use, younger age, and prior COVID-19 history. Following booster vaccination, females and Hispanics had higher peak titers after the 3rd and 4th doses, respectively. Longitudinal models demonstrated that Moderna mRNA-1273 recipients, females, and those previously vaccinated had increased peak titers over time. Moreover, drug users and half-dose Moderna mRNA-1273 recipients had higher peak antibody titers over time following the first booster, while no predictive factors significantly affected post-second booster antibody responses. Overall, both intrinsic and extrinsic health factors play a significant role in shaping humoral immunogenicity after initial vaccination and the first booster. The absence of predictive factors for second booster immunogenicity suggests a more robust and consistent immune response after the second booster vaccine administration.

Temporal changes in factors associated with COVID-19 vaccine hesitancy among Chinese adults: Repeated nationally representative survey

Background

COVID-19 vaccine hesitancy has been cited as one of the main obstacles impacting vaccine coverage. However, factors that affect hesitancy may change over time. Understanding these evolving concerns and adapting strategies accordingly are crucial for effectively addressing vaccine hesitancy effectively and promoting public health. We aimed to explore the temporal changes in factors associated with COVID-19 VH during the COVID-19 pandemic and assess the dynamic evolution of VH.

Methods

In August 2022 and February 2023, repeated online surveys were undertaken to collect information from 5378 adults across four regions of China. Multiple linear regression models assessed the influencing factors of COVID-19 VH. The association between protective motive theory (PMT) (perceived severity, susceptibility, benefits, barriers, and self-efficacy) and VH was evaluated by structural equation modeling (SEM).

Results

Repeated measures showed that 573 (10.7%) and 1598 (29.7%) of the 5378 participants reported COVID-19 VH in the baseline and follow-up surveys, respectively. Educational levels, chronic disease, history of allergy, COVID-19 infection, and trust in medical staff and vaccine developers were positively associated with COVID-19 VH (P＜0.05). The application of SEM revealed that perceived severity, susceptibility, vaccination barriers, and self-efficacy in the PMT directly impacted on VH (P＜0.05). In addition, severity, susceptibility, benefits, and barriers had a significant direct effect on self-efficacy as β = 0.113, β = 0.070, β = 0.722, β = -0.516 respectively with P < 0.001.

Conclusion

The prevalence of COVID-19 VH was relatively low in the baseline survey and much higher in the follow-up survey, with a significant increase in hesitancy rates among mainland Chinese residents. Acknowledging the substantial impact on the shaping of COVID-19 VH, one must consider factors including perceived severity, susceptibility, vaccination barriers, and self-efficacy.

Seroprevalence of anti-SARS-CoV-2 IgG antibodies pre- and post-COVID-19 vaccination in staff members of Bandar Abbas Children's Hospital

BACKGROUND

Healthcare workers (HCWs) have a higher risk of contracting coronavirus disease 2019 (COVID-19) compared to the general population due to their frontline role and direct contact with the infected patients. Accordingly, they were among the first groups to receive vaccination against COVID-19. A higher risk of COVID-19 infection may also exist among hospital staff members other than HCWs. In this study, we assessed the seroprevalence of anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) IgG pre- and post-COVID-19 vaccination in hospital staff members.

METHODS

This cross-sectional study included 228 staff members of Bandar Abbas Children's Hospital, Bandar Abbas, Iran, who were recruited from 2020 to 2021. Staff members were vaccinated with vector and inactivated vaccines. Anti-SARS-CoV-2 spike protein IgG was measured in their blood samples pre- and post-COVID-19 vaccination.

RESULTS

Of the 228 hospital staff members evaluated in this study (mean age: 37.59 ± 8.70 years), 204 (89.5%) were female and 210 (92.1%) were HCWs. Only one staff member was not vaccinated, the rest received one dose (99.6%), and 224 (98.7%) two doses. Vector vaccines were administered to 71.4% of staff members and 72.9% of HCWs. Anti-SARS-CoV-2 IgG antibody was positive in 8.8% of staff members before vaccination, 9.3% after the first dose, and 50% after the second dose. The corresponding percentages were 9.5%, 9.5%, and 48.8% in HCWs. Being a HCW was not associated with the seroprevalence of anti-SARS-CoV-2 IgG after the second dose; however, multivariable binary logistic regression analysis revealed that the interval between two vaccine doses (adjusted odds ratio [aOR] = 0.595, 95% confidence interval [CI] 0.434; 0.816, P = 0.001) and age (aOR = 1.062, 95% CI 1.021; 1.105, P = 0.003) were associated with seroprevalence.

CONCLUSIONS

After receiving a second dose of vector or inactive virus vaccines, our hospital's staff members and HCWs had a seroprevalence of anti-SARS-CoV-2 IgG antibodies of around 50%. Seroprevalence increased with increasing age and shorter intervals between doses.

Determinants of SARS-CoV-2 IgG response and decay in Canadian healthcare workers: A prospective cohort study

INTRODUCTION

Healthcare workers (HCWs) from an interprovincial Canadian cohort gave serial blood samples to identify factors associated with anti-receptor binding domain (anti-RBD) IgG response to the SARS-CoV-2 virus.

METHODS

Members of the HCW cohort donated blood samples four months after their first SARS-CoV-2 immunization and again at 7, 10 and 13 months. Date and type of immunizations and dates of SARS-CoV-2 infection were collected at each of four contacts, together with information on immunologically-compromising conditions and current therapies. Blood samples were analyzed centrally for anti-RBD IgG and anti-nucleocapsid IgG (Abbott Architect, Abbott Diagnostics). Records of immunization and SARS-CoV-2 testing from public health agencies were used to assess the impact of reporting errors on estimates from the random-effects multivariable model fitted to the data.

RESULTS

2752 of 4567 vaccinated cohort participants agreed to donate at least one blood sample. Modelling of anti-RBD IgG titer from 8903 samples showed an increase in IgG with each vaccine dose and with first infection. A decrease in IgG titer was found with the number of months since vaccination or infection, with the sharpest decline after the third dose. An immunization regime that included mRNA1273 (Moderna) resulted in higher anti-RBD IgG. Participants reporting multiple sclerosis, rheumatoid arthritis or taking selective immunosuppressants, tumor necrosis factor inhibitors, calcineurin inhibitors and antineoplastic agents had lower anti-RBD IgG. Supplementary analyses showed higher anti-RBD IgG in those reporting side-effects of vaccination, no relation of anti-RBD IgG to obesity and lower titers in women immunized in early or mid-pregnancy. Sensitivity analysis results suggested no important bias in the self-report data.

CONCLUSION

Creation of a prospective cohort was central to the credibility of results presented here. Serial serology assessments, with longitudinal analysis, provided effect estimates with enhanced accuracy and a clearer understanding of medical and other factors affecting response to vaccination.

Covid-19 vaccination coverage and associated factors among older hypertensive patients in Hangzhou, China

BACKGROUND

Vaccination could provide effective protection against coronavirus disease 2019 (COVID-19). This study aims to describe the COVID-19 vaccination coverage and influential factors in Chinese older hypertensive patients.

METHODS

Using a cross-sectional design, participants were randomly selected from the electronic health records system during the pandemic era in Hangzhou, China. Logistic regression models were employed to compute the OR and 95% CI in order to assess the relationships between variables and the extent of COVID-19 vaccination coverage.

RESULTS

As of 3 August 2022, among a sample of 77 970 individuals, 75.11% had completed the full COVID-19 vaccination, while 57.66% had received a booster dose. Disparities in coverage were observed across genders, regions and age groups. Unhealthy lifestyles, cardiovascular disease, cancer, uncontrolled blood pressure, abnormal fasting plasma glucose, dyslipidemia and renal dysfunction were risk factors for COVID-19 vaccination coverage. The coverage rates continuously declined along with the number of risk factors. The ORs for full and booster vaccination in subjects with ≥4 risk factors were 2.55 (2.12∼3.07) and 2.60 (2.16∼3.13), compared to individuals without risk factors.

CONCLUSION

The COVID-19 vaccination program for older hypertensive patients must be strengthened further. Emphasis should be placed on patients who reside in urban areas, have comorbidities or multiple risk factors.

Evaluation of SARS-CoV-2 Antibody Levels in Pharmacists and Pharmacy Staff Following CoronaVac Vaccination

Objectives

The aim of this study was to determine the seropositivity rate of pharmacists and pharmacy staff after the administration of two doses of the CoronaVac-SinoVac vaccine and to assess changes in their antibody levels according to sociodemographic characteristics.

Materials and Methods

This descriptive study was conducted between June 04, 2021 and September 30, 2021 in pharmacies located in Istanbul, Türkiye. The results of self-initiated immunoglobulin (Ig) G testing of the pharmacists and pharmacy staff, conducted at diagnostic laboratories contracted by the Istanbul Chamber of Pharmacists, were obtained using an online data collection tool. IgG measurements taken from 15 days up to 120 days after the two vaccine doses were included in the study. Participants were asked whether they smoked, had any chronic diseases (hypertension, chronic obstructive pulmonary disease, asthma, diabetes, etc.), or took any medications. Subgroup analyses were performed for each method used to measure antibody levels.

Results

The study included 329 pharmacists/pharmacy staff (298 pharmacists and 31 pharmacy staff). The mean age of the participants was 49.7 ± 13.7 years, and 71.4% were female. The antibody positivity of the 329 participants was 94.9% following the two doses. The positivity rate was 95.4% in participants under 65 years of age, whereas it was 91.8% in those aged 65 years and over. There was no significant difference in the mean age between those with positive and negative antibody results (p > 0.05). Although antibody levels were lower older people, smokers, and those with chronic diseases, this difference was not statistically significant (p > 0.05).

Conclusion

Seropositivity developed following the administration of two doses of CoronaVac-Sinovac vaccines. IgG antibody levels were lower in older adults, smokers, and those with chronic diseases, although not to a statistically significant extent. Further studies are needed to better understand the reasons for the different immunological responses to COVID-19.

A Potential Association between Abdominal Obesity and the Efficacy of Humoral Immunity Induced by COVID-19 and by the AZD1222, Convidecia, BNT162b2, Sputnik V, and CoronaVac Vaccines

Abdominal obesity is highly prevalent in Mexico and has a poor prognosis in terms of the severity of coronavirus disease (COVID-19) and low levels of antibodies induced by infection and vaccination. We evaluated the humoral immune response induced by COVID-19 and five different vaccination schedules in Mexican individuals with abdominal obesity and the effects of other variables. This prospective longitudinal cohort study included 2084 samples from 389 participants. The levels of anti-S1/S2 and anti-RBD IgG antibodies were measured at various time points after vaccination. A high prevalence of hospitalization and oxygen use was observed in individuals with abdominal obesity (AO) who had COVID-19 before vaccination; however, they also had high levels of anti-S1/S2 and anti-RBD-neutralizing IgG antibodies. The same was true for vaccination-induced antibody levels. However, their longevity was low. Interestingly, we did not observe significant differences in vaccine reactogenicity between abdominally obese and abdominally non-obese groups. Finally, individuals with a higher body mass index, older age, and previous COVID-19 had higher levels of antibodies induced by COVID-19 and vaccination. Therefore, it is important to evaluate other immunological and inflammatory factors to better understand the pathogenesis of COVID-19 in the presence of risk factors and to propose effective vaccination schedules for vulnerable populations.

Reported side-effects following Oxford/AstraZeneca COVID-19 vaccine in the north-west province, Iran: A cross-sectional study

While the vaccination was introduced as a promising tool to control the Coronavirus disease 2019 (COVID-19) pandemic, concerns about vaccine-related side effects had grown. Due to the widespread administration of the COVID-19 vaccine worldwide for the first time, it was necessary to evaluate the safety and potential side effects in recipients. This study aims to assess, the incidence of adverse effects following Oxford-AstraZeneca vaccination and identify their related factors. In this cross-sectional survey-based study, 453 volunteers participated, including 235 men and 218 women. The reported adverse reactions from recipients of the ChAdOx1 nCoV-19 (Oxford-AstraZeneca) vaccine were collected by using a questionnaire. The findings showed that the incidence of adverse reactions, such as neurological, systematic, gastrointestinal, respiratory, and local symptoms were significantly higher after the first dose compared to the second dose. Systematic symptoms were the most prevalent reported side effects after the first and second dose injection. The demographical study of participants showed that individuals aged 18-34 and females were more prone to present adverse events following vaccination. However, no significant relationship was found between the occurrence of side effects and the recipients' body mass index. Despite the life-saving role of vaccination against SARS-CoV-2, it may have some adverse reactions in recipients. The severity and frequency of side effects were different. So, they were dependent on several factors, including gender and age. Altogether, post-vaccination adverse reactions were mild and tolerable.

An mRNA vaccine encoding the SARS-CoV-2 receptor-binding domain protects mice from various Omicron variants

Here, we assessed the efficacy of a lipid nanoparticle-based mRNA vaccine candidate encoding the receptor-binding domain (LNP-mRNA-RBD) in mice. Mice immunized with LNP-mRNA-RBD based on the ancestral strain (ancestral-type LNP-mRNA-RBD) showed similar cellular responses against the ancestral strain and BA.5, but their neutralizing activity against BA.5 was lower than that against the ancestral strain. The ancestral-type LNP-mRNA-RBD protected mice from the ancestral strain or BA.5 challenge; however, its ability to reduce the viral burdens after BA.5 challenge was limited. In contrast, immunization with bivalent LNP-mRNA-RBD consisting of the ancestral-type and BA.4/5-type LNP-mRNA-RBD or monovalent BA.4/5-type LNP-mRNA-RBD elicited robust cellular responses, as well as high and moderate neutralizing titers against BA.5 and XBB.1.5, respectively. Furthermore, the vaccines containing BA.4/5-type LNP-mRNA-RBD remarkably reduced the viral burdens following BA.5 or XBB.1.5 challenge. Overall, our findings suggest that LNP-mRNA-RBD is effective against SARS-CoV-2 infection.

Factors associated with IgG titers against SARS-CoV-2 spike protein after second vaccination in people living with HIV controlled with anti-retroviral therapy

OBJECTIVE

This study aimed to identify factors associated with the response to the SARS-CoV-2 vaccine in people living with HIV (PLWH).

METHODS

This study was conducted at the Jikei University School of Medicine, Tokyo, Japan. IgG antibodies against spike and nucleocapsid proteins were detected using Abbott SARS-CoV-2 IgG II Quant assays.

RESULTS

During the investigation period, 371 PLWH were enrolled in this study. PLWH with previous COVID-19 infection, untreated or poorly controlled HIV infection, and those whose blood samples were obtained within less than seven days after the second vaccination were excluded. A total of 310 PLWH controlled with anti-retroviral therapy were included in the final analysis. Multivariate analysis demonstrated that chronic kidney disease (CKD) (β = -0.353, p = 0.049) and the duration between the second vaccination and blood sampling (β = -0.005, p < 0.001) were associated with low spike protein IgG titers.

CONCLUSION

Even without hemodialysis or kidney transplant, CKD was associated with vaccine response in PLWH.

Mediating factors explain anxiety experienced by women with obesity during the Covid-19 pandemic

The Covid-19 pandemic could be a source of great anxiety, especially for those at higher risk, such as women experiencing obesity. The aim of this study was to measure how some personal characteristics such as BMI (from underweight to class 3 obesity), bariatric surgery (yes or no), comorbidities, or age (as antecedent variables), and mediating factors impacted state anxiety during the Covid-19 Pandemic. Mediating factors were related to subjective knowledge or attitudes (e.g. interest or beliefs and practices around Covid-19, subjective health perception, and confidence in the government). French women (N = 532) were invited to take part in a voluntary online health survey during lockdown in Paris and its suburbs. Results showed that women with higher BMI had higher anxiety scores, primarily because they feel less healthy than other people. Secondly, the larger the body size of the participants was (BMI), the less they reported that information about Covid-19 held their attention. This lack of interest resulted in feelings of anxiety not being generated. Thirdly, the larger their body size was, the less confidence they had in the effectiveness of the proposed measures by the government and therefore, the more anxious they were. Finally, older age predicted higher interest in the pandemic, higher subjective health, and higher confidence in the government. Identifying obesity as a potential risk factor for anxiety disorders is crucial, but measuring the relationship between state anxiety and personal characteristics (e.g. BMI) requires considering mediating variables (e.g. subjective health perception). To reduce anxiety in women with obesity, it appears necessary to focus on psychological programs that can help them improve their perception of their health, as well as the confidence they may have in institutions, especially for younger women.

Obesity and COVID-19 Pandemics: Epidemiology, Mechanisms, and Management

Obesity is a principle causative factor of various metabolic dysfunctions, chronic inflammation, and multi-organ impairment. The global epidemic of obesity has constituted the greatest threat to global health. Emerging evidence has associated obesity with an increased risk of severe infection and poor outcomes from coronavirus disease 2019 (COVID-19). During current COVID-19 pandemic, the interaction between COVID-19 and obesity has exaggerated the disease burden of obesity more than ever before. Thus, there is an urgent need for consideration of universal measures to reduce the risk of complications and severe illness from severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) in obesity population. In this review, we first summarized the clinical evidence on the effect of obesity on susceptibility, severity, and prognosis of COVID-19. Then we discussed and the underlying mechanisms, including respiratory pathophysiology of obesity, dysregulated inflammation, upregulated angiotensin-converting enzyme 2 (ACE2) expression, hyperglycemia, and adipokines. Finally, we proposed recommendations on how to reduce the spread and pandemic of SARS-CoV-2 infection by prevention and treatment of obesity.

Employment of a high throughput functional assay to define the critical factors that influence vaccine induced cross-variant neutralizing antibodies for SARS-CoV-2

The scale and duration of neutralizing antibody responses targeting SARS-CoV-2 viral variants represents a critically important serological parameter that predicts protective immunity for COVID-19. In this study, we describe the development and employment of a new functional assay that measures neutralizing antibodies for SARS-CoV-2 and present longitudinal data illustrating the impact of age, sex and comorbidities on the kinetics and strength of vaccine-induced antibody responses for key variants in an Asian volunteer cohort. We also present an accurate quantitation of serological responses for SARS-CoV-2 that exploits a unique set of in-house, recombinant human monoclonal antibodies targeting the viral Spike and nucleocapsid proteins and demonstrate a reduction in neutralizing antibody titres across all groups 6 months post-vaccination. We also observe a marked reduction in the serological binding activity and neutralizing responses targeting recently newly emerged Omicron variants including XBB 1.5 and highlight a significant increase in cross-protective neutralizing antibody responses following a third dose (boost) of vaccine. These data illustrate how key virological factors such as immune escape mutations combined with host demographic factors such as age and sex of the vaccinated individual influence the strength and duration of cross-protective serological immunity for COVID-19.

Elevated BMI reduces the humoral response to SARS-CoV-2 infection

Objective

Class III obesity (body mass index [BMI] ≥ 40 kg m-2) significantly impairs the immune response to SARS-CoV-2 vaccination. However, the effect of an elevated BMI (≥ 25 kg m-2) on humoral immunity to SARS-CoV-2 infection and COVID-19 vaccination remains unclear.

Methods

We collected blood samples from people who recovered from SARS-CoV-2 infection approximately 3 and 13 months of post-infection (noting that these individuals were not exposed to SARS-CoV-2 or vaccinated in the interim). We also collected blood samples from people approximately 5 months of post-second dose COVID-19 vaccination (the majority of whom did not have a prior SARS-CoV-2 infection). We measured their humoral responses to SARS-CoV-2, grouping individuals based on a BMI greater or less than 25 kg m-2.

Results

Here, we show that an increased BMI (≥ 25 kg m-2), when accounting for age and sex differences, is associated with reduced antibody responses after SARS-CoV-2 infection. At 3 months of post-infection, an elevated BMI was associated with reduced antibody titres. At 13 months of post-infection, an elevated BMI was associated with reduced antibody avidity and a reduced percentage of spike-positive B cells. In contrast, no significant association was noted between a BMI ≥ 25 kg m-2 and humoral immunity to SARS-CoV-2 at 5 months of post-secondary vaccination.

Conclusions

Taken together, these data showed that elevated BMI is associated with an impaired humoral immune response to SARS-CoV-2 infection. The impairment of infection-induced immunity in individuals with a BMI ≥ 25 kg m-2 suggests an added impetus for vaccination rather than relying on infection-induced immunity.

Nutrition, Immune Function, and Infectious Disease in Military Personnel: A Narrative Review

Consuming a diet that meets energy demands and provides essential nutrients promotes a healthy immune system, while both under- and over-nutrition have been associated with immune dysfunction. Military personnel comprise a unique population who frequently endure multi-stressor environments, predisposing them to immune decrements. Additionally, 49% and 22% of active duty U.S. military personnel are classified as overweight and obese, respectively. A literature search on PubMed was conducted to identify studies, reports, review papers, and references within those sources relevant to the topic area. Military personnel experiencing either under- or over-nutrition can suffer from degraded health, readiness, and performance. Insufficient intake of nutrients during military operations increases infection risk and negatively impacts infection recovery. Energy, protein, iron, zinc, and vitamins C and D are nutritional areas of concern that may impact immune competence in a multi-stressor environment. Over-nutrition can promote accretion of excess body fat and obesity, which contributes to a chronic inflammatory state that coincides with immune impairments. Prioritizing efforts to optimize nutrient intake is one approach for reducing disease burden and improving readiness. This review discusses nutritional concerns concomitant to multi-stressor environments that impact immune function, and the relevance of obesity to infectious disease risk in the military population.

Effect of SARS-CoV-2 vaccination in a vulnerable COVID-19 cohort: a real-life experience in an Italian Hospital

Clinical trials demonstrated that SARS-CoV-2 vaccines reduce COVID-19-related mortality and morbidity. We describe the effect of vaccination on COVID-19-patients admitted at our hospital. Retrospective, single-center study conducted in Genoa, Italy, including patients ≥18years hospitalized for COVID-19 from May to December 2021. Demographical and clinical data were collected, vaccinated (group-A) and not-vaccinated (group-B) patients were compared. Impact of vaccination on mortality, ICU admission, and oxygen need was studied using Cox proportional hazards and logistic regression models after adjusting for propensity scores. Overall, 395 patients SARS-CoV-2 infected were included, of which 150 (38%) were vaccinated and 245 (62%) were not vaccinated. Patients in group-A were older, more disable, and with higher morbidity. Overall, 64 patients (16%) died within 30 days from admission, 34 in Group A (23%), and 30 in group B (12%). However, no statistically significant differences were observed (group-A versus group-B: HR 0.83, 95% CI 0.49-1.40, p = 0.483). On the other hand, vaccination was protective in terms of ICU admission (OR = 0.23, p = 0.046) and oxygen need (OR = 0.33, p = 0.008). Our study confirms that SARS-CoV-2 vaccination reduces morbidity among patients hospitalized for COVID-19. The still high mortality in our cohort of vaccinated individuals could be partially due to vulnerable conditions of our patients.

BNT162b2 Booster Dose Elicits a Robust Antibody Response in Subjects with Abdominal Obesity and Previous SARS-CoV-2 Infection

Little is known about the long-term durability of the induced immune response in subjects with obesity, particularly in those with an abdominal distribution of adipose tissue. We evaluated SARS-CoV-2-specific antibody responses after BNT162b2 vaccine booster dose, comparing individuals with and without abdominal obesity (AO), discerning between individuals previously infected or not. IgG-TrimericS were measured in 511 subjects at baseline, on the 21st day after vaccine dose 1, and at 1, 3, 6, and 9 months from dose 2, and at 1 and 3 months following the booster dose. To detect SARS-CoV-2 infection, nucleocapsid antibodies were measured at baseline and at the end of the study. Multivariable linear regression evaluated the three-month difference in the absolute variation in IgG-TrimericS levels from booster dose, showing AO and SARS-CoV-2 infection status interactions (p = 0.016). Regardless of possible confounding factors and IgG-TrimericS levels at the booster dose, AO is associated with a higher absolute change in IgG-TrimericS in prior infected individuals (p = 0.0125). In the same regression model, no interaction is highlighted using BMI (p = 0.418). The robust response in the development of antibodies after booster dose, observed in people with AO and previous infection, may support the recommendations to administer a booster dose in this population group.

Monitoring of antibody levels in healthcare workers after inactivated coronavirus disease 19 vaccination

OBJECTIVE

Because of the coronavirus disease 19 pandemic, studies on vaccination are being conducted in our country as well as across the world. In this study, the antibody levels in healthcare workers vaccinated with two doses of inactivated vaccine and the factors affecting these levels were investigated.

METHODS

Randomly selected volunteers from healthcare workers, who had been vaccinated with two doses of inactivated vaccine in January to February 2021, were included in the study. Blood samples were drawn twice, 1 month and 6 months after the second dose vaccine (CoronaVac:Sinovac Life Science Co, Ltd, Beijing, China). The antibody levels were determined by the chemiluminescence microparticle immunoassay method using kits for quantitative detection of immunoglobulin class G antibodies to severe acute respiratory syndrome coronavirus 2.

RESULTS

The mean antibody levels of 129 volunteers were 1232.5 (min: 103 to max: 7151) AU/mL in the first month and 403.5 (min: 23 to max: 4963) AU/mL in the sixth month. According to the survey results, 91 (71%) volunteers had not been diagnosed with coronavirus disease 19 before vaccination. The antibody levels 1 month and 6 months after the second dose of vaccination were significantly higher in those who had been diagnosed with coronavirus disease 19 before vaccination than in those who had not. It was found that age, gender, fast food, or healthy nutrition had no effect on antibody levels.

CONCLUSION

Vaccines are very important both to protect against coronavirus disease 19 and to experience only a mild form of the disease. Immunoglobulin class G levels formed after vaccination may be affected by many factors and may decrease over time.

Impact of vaccination against severe COVID-19 in the French population aged 50 years and above: a retrospective population-based study

BACKGROUND

Given the widespread implementation of COVID-19 vaccination to mitigate the pandemic from the end of 2020, it is important to retrospectively evaluate its impact, in particular by quantifying the number of severe outcomes prevented through vaccination.

METHODS

We estimated the number of hospitalizations, intensive care unit (ICU) admissions and deaths directly averted by vaccination in France, in people aged ≥ 50 years, from December 2020 to March 2022, based on (1) the number of observed events, (2) vaccination coverage, and (3) vaccine effectiveness. We accounted for the effect of primary vaccination and the first booster dose, the circulating variants, the age groups, and the waning of vaccine-induced protection over time.

RESULTS

An estimated 480,150 (95% CI: 260,072-582,516) hospitalizations, 132,156 (50,409-157,767) ICU admissions and 125,376 (53,792-152,037) deaths were directly averted by vaccination in people aged ≥ 50 years, which corresponds to a reduction of 63.2% (48.2-67.6), 68.7% (45.6-72.4) and 62.7% (41.9-67.1) respectively, compared to what would have been expected without vaccination over the study period. An estimated 5852 (2285-6853) deaths were directly averted among the 50-59 years old, 16,837 (6568-19,473) among the 60-69 years old, 32,136 (13,651-36,758) among the 70-79 years old and 70,551 (31,288-88,953) among the ≥ 80 years old.

CONCLUSIONS

The vaccination campaign in France considerably reduced COVID-19 morbidity and mortality, as well as stress on the healthcare system.

Multifaceted effects of obesity on cancer immunotherapies: Bridging preclinical models and clinical data

Obesity, defined by excessive body fat, is a highly complex condition affecting numerous physiological processes, such as metabolism, proliferation, and cellular homeostasis. These multifaceted effects impact cells and tissues throughout the host, including immune cells as well as cancer biology. Because of the multifaceted nature of obesity, common parameters used to define it (such as body mass index in humans) can be problematic, and more nuanced methods are needed to characterize the pleiotropic metabolic effects of obesity. Obesity is well-accepted as an overall negative prognostic factor for cancer incidence, progression, and outcome. This is in part due to the meta-inflammatory and immunosuppressive effects of obesity. Immunotherapy is increasingly used in cancer therapy, and there are many different types of immunotherapy approaches. The effects of obesity on immunotherapy have only recently been studied with the demonstration of an "obesity paradox", in which some immune therapies have been demonstrated to result in greater efficacy in obese subjects despite the direct adverse effects of obesity and excess body fat acting on the cancer itself. The multifactorial characteristics that influence the effects of obesity (age, sex, lean muscle mass, underlying metabolic conditions and drugs) further confound interpretation of clinical data and necessitate the use of more relevant preclinical models mirroring these variables in the human scenario. Such models will allow for more nuanced mechanistic assessment of how obesity can impact, both positively and negatively, cancer biology, host metabolism, immune regulation, and how these intersecting processes impact the delivery and outcome of cancer immunotherapy.

A Systematic Evaluation of the SARS-CoV-2 Vaccine-Induced Anti-S-RBD-Ig Response in a Population of Health Care Workers

In the wake of the COVID-19 pandemic, the novel class of mRNA vaccines has been granted first-time approval for active immunization against SARS-CoV-2 alongside the already established viral vector-based vaccines. In this prospective single-center study, we set out to determine the vaccine-induced humoral immune response in a population of 1512 health care employees after the second and third vaccination, respectively. Anti-SARS-CoV-2 receptor-binding domain (RBD) and nucleocapsid antigen antibody concentrations were assessed using commercially available immunoassays. We could show that, in particular, young study subjects aged below 30 years, as well as those with a prior SARS-CoV-2 infection, developed significantly higher antibody concentrations. Our data further suggest that being in physically close contact with formerly SARS-CoV-2-positive people positively affects the post-vaccination response. Surprisingly, study subjects with a BMI > 30 produced the highest anti-S-RBD Ig antibody levels if they had recently received their third vaccination. Also, heterologous dual vaccine regimens consisting of a BNT162b2 and ChAdOx1 n-CoV-19, a homologous triple combination of BNT162b2, and an application of mRNA-1273 as the third vaccine, were most efficient at eliciting a humoral immune response. Our study substantiates existing evidence, but beyond that, scrutinizes the impact of vaccine agents and their respective combinations, as well as different time intervals on humoral immunogenicity.

Bidirectionality between Cardiometabolic Diseases and COVID-19: Role of Humoral Immunity

Cardiometabolic diseases and abnormalities have recently emerged as independent risk factors of coronavirus disease 2019 (COVID-19) severity, including hospitalizations, invasive mechanical ventilation, and mortality. Determining whether and how this observation translates to more effective long-term pandemic mitigation strategies remains a challenge due to key research gaps. Specific pathways by which cardiometabolic pathophysiology affects humoral immunity against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), and vice versa, remain unclear. This review summarizes current evidence of the bidirectional influences between cardiometabolic diseases (diabetes, adiposity, hypertension, CVDs) and SARS-CoV-2 antibodies induced from infection and vaccination based on human studies. Ninety-two studies among >408,000 participants in 37 countries on 5 continents (Europe, Asia, Africa, and North and South America) were included in this review. Obesity was associated with higher neutralizing antibody titers following SARS-CoV-2 infection. Most studies conducted prior to vaccinations found positive or null associations between binding antibodies (levels, seropositivity) and diabetes; after vaccinations, antibody responses did not differ by diabetes. Hypertension and CVDs were not associated with SARS-CoV-2 antibodies. Findings underscore the importance of elucidating the extent that tailored recommendations for COVID-19 prevention, vaccination effectiveness, screening, and diagnoses among people with obesity could reduce disease burden caused by SARS-CoV-2.

Vaccine-elicited B- and T-cell immunity to SARS-CoV-2 is impaired in chronic lung disease patients

Background

While vaccination against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) provides significant protection from coronavirus disease 2019, the protection afforded to individuals with chronic lung disease is less well established. This study seeks to understand how chronic lung disease impacts SARS-CoV-2 vaccine-elicited immunity.

Methods

Deep immune phenotyping of humoral and cell-mediated responses to the SARS-CoV-2 vaccine was performed in patients with asthma, COPD and interstitial lung disease (ILD) compared to healthy controls.

Results

48% of vaccinated patients with chronic lung diseases had reduced antibody titres to the SARS-CoV-2 vaccine antigen relative to healthy controls. Vaccine antibody titres were significantly reduced among asthma (p<0.035), COPD (p<0.022) and a subset of ILD patients as early as 3-4 months after vaccination, correlating with decreased vaccine-specific memory B-cells in circulation. Vaccine-specific memory T-cells were significantly reduced in patients with asthma (CD8+ p<0.004; CD4+ p<0.023) and COPD (CD8+ p<0.008) compared to healthy controls. Impaired T-cell responsiveness was also observed in a subset of ILD patients (CD8+ 21.4%; CD4+ 42.9%). Additional heterogeneity between healthy and disease cohorts was observed among bulk and vaccine-specific follicular T-helper cells.

Conclusions

Deep immune phenotyping of the SARS-CoV-2 vaccine response revealed the complex nature of vaccine-elicited immunity and highlights the need for more personalised vaccination schemes in patients with underlying lung conditions.

Comparative analysis of the effectiveness difference of SARS-COV-2 mRNA vaccine in different populations in the real world: A review

Coronavirus disease 2019 (COVID-19) has ravaged the world since December 2019. Up to now, it is still prevalent around the world. Vaccines are an important means to prevent the spread of COVID-19 and reduce severe disease and mortality. Currently, different types of novel coronavirus vaccines are still being developed and improved, and the relevant vaccines that have been approved for marketing have been widely vaccinated around the world. As vaccination coverage continues to grow, concerns about the efficacy and safety of vaccines after real-world use have grown. Some clinical studies have shown that vaccine effectiveness is closely related to antibody response after vaccination. Among them, the advantages of COVID-19 messenger ribonucleic acid (mRNA) vaccine, such as better adaptability to variant strains and better immune response ability, have attracted great attention. However, different populations with different genders, ages, previous COVID-19 infection history, underlying diseases and treatments will show different antibody responses after mRNA vaccination, which will affect the protection of the vaccine. Based on this, this paper reviews the reports related severe acute respiratory syndrome Coronavirus 2 mRNA vaccines, and summarizes the effectiveness of vaccines in different populations and different disease states and looked forward to the precise vaccination strategy of the vaccine in the future.

A Comparative Study of Immunogenicity, Antibody Persistence, and Safety of Three Different COVID-19 Boosters between Individuals with Comorbidities and the Normal Population

Data on immunogenicity, immune response persistency, and safety of COVID-19 boosters in patients with comorbidities are limited. Therefore, we aimed to evaluate three different boosters' immunogenicity and safety in individuals with at least one underlying disease (UD) (obesity, hypertension, and diabetes mellitus) with healthy ones (HC) who were primed with two doses of the BBIBP-CorV vaccine and received a booster shot of the same priming vaccine or protein subunit vaccines, PastoCovac Plus or PastoCovac. One hundred and forty subjects including sixty-three ones with a comorbidity and seventy-seven healthy ones were enrolled. The presence of SARS-CoV-2 antibodies was assessed before the booster injection and 28, 60, 90, and 180 days after it. Moreover, the adverse events (AEs) were recorded on days 7 and 21 postbooster shot for evaluating safety outcomes. Significantly increased titers of antispike, antiRBD, and neutralizing antibodies were observed in both UD and HC groups 28 days after the booster dose. Nevertheless, the titer of antispike IgG and anti-RBD IgG was lower in the UD group compared to the HC group. The long-term assessment regarding persistence of humoral immune responses showed that the induced antibodies were detectable up to 180 days postbooster shots though with a declined titer in both groups with no significant differences (p > 0.05). Furthermore, no significant difference in antibody levels was observed between each UD subgroup and the HC group, except for neutralizing antibodies in the hypertension subgroup. PastoCovac Plus and PastoCovac boosters induced a higher fold rise in antibodies in UD individuals than BBIBP-CorV booster recipients. No serious AEs after the booster injection were recorded. The overall incidence of AEs after the booster injection was higher in the UD group than the HC group among whom the highest systemic rate of AEs was seen in the BBIBP-CorV booster recipients. In conclusion, administration of COVID-19 boosters could similarly induce robust and persistent humoral immune responses in individuals with or without UD primarily vaccinated with two doses of the BBIBP-CorV. Protein-based boosters with higher a higher fold rise in antibodies and lower AEs in individuals with comorbidities might be considered a better choice for these individuals.

The Effect of Smoking on Inactivated and mRNA Vaccine Responses Applied to Prevent COVİD-19 in Multiple Sclerosis

Introduction

Coronavirus disease 2019 (COVID-19) is the biggest health challenge of recent times. Studies so far reveal that vaccination is the only way to prevent this pandemic. There may be factors that decrease or increase vaccine effectiveness. In multiple sclerosis (MS), some of these factors may cause changes in the effectiveness of the vaccine, depending on the nature of the disease and disease-modifying treatments (DMT). In this study, we aimed to investigate the relationship between antibody titer and smoking in non-treated and DMT-treated MS patients who received inactivated vaccine (Sinovac) and messenger RNA BNT162b2 (BioNTech) mRNA vaccines.

Method

Vaccine antibody responses were measured between 4-12 weeks after two doses of inactivated vaccine and mRNA vaccines. Patients were separated into 6 groups as: patients with MS without treatment PwMS w/o T, ocrelizumab, fingolimod, interferons (interferon beta-1a and interferon beta-1b), dimethyl fumarate, and teriflunomide. Antibody titers of smokers and non-smokers were compared for both vaccines and for each group.

Results

The study included 798 patients. In the mRNA vaccine group, smokers (n=148; 2982±326 AU/mL) had lower antibody titers compared to the non-smokers (n=244; 5903±545 AU/mL) in total (p=0.020). In the inactivated vaccine group, no significant difference was detected between smokers (n=136; 383±51 AU/mL) and non-smokers (n=270; 388±49 AU/mL) in total (p=0.149). In both vaccine groups, patients receiving ocrelizumab and fingolimod had lower antibody titers than those receiving other DMTs or PwMS w/o T. In untreated MS patients, antibody levels in smokers were lower than in non-smokers in the mRNA vaccine group. No difference was found between antibody levels of smokers and non-smokers in any of the inactivated vaccine groups.

Conclusion

Ocrelizumab and fingolimod have lower antibody levels than PwMS w/o T or other DMTs in both mRNA and inactivated vaccine groups. Smoking decreases antibody levels in the mRNA vaccine group, while it has no effect in the inactivated vaccine group.

MicroRNAs Derived from Extracellular Vesicles: Keys to Understanding SARS-CoV-2 Vaccination Response in Cancer Patients?

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) provoked a global pandemic identified as coronavirus disease (COVID-19), with millions of deaths worldwide. However, several important questions regarding its impact on public health remain unanswered, such as the impact of vaccination on vulnerable subpopulations such as cancer patients. Cytokine storm and a sustained inflammatory state are commonly associated with immune cell depletion, being manifested in most immunocompromised individuals. This strong immunosuppression can lead to a dysfunctional antiviral response to natural viral infection and compromised vaccination response. Extracellular vesicles (EVs) are membrane-bound vesicles released from cells that are involved in intercellular communication. EVs carry various molecules including microRNAs that play a crucial role in COVID-19 pathophysiology, influencing cellular responses. This review summarizes the state of the art concerning the role of EV-derived miRNAs in COVID-19 infection and their potential use as prognosis biomarkers for vaccination response in cancer patients.

Factors associated with antibody titer levels among an occupational cohort of fully vaccinated individuals and subsequent risk of COVID-19 infection: A cohort study

This study (1) determined the association of time since initial vaccine regimen, booster dose receipt, and COVID-19 history with antibody titer, as well as change in titer levels over a defined period, and (2) determined risk of COVID-19 associated with low titer levels. This observational study used data from staff participating in the National Football League COVID-19 Monitoring Program. A cohort of staff consented to antibody-focused sub-study, during which detailed longitudinal data were collected. Among all staff in the program who received antibody testing, COVID-19 incidence following antibody testing was determined. Five hundred eighty-six sub-study participants completed initial antibody testing; 80% (469) completed follow-up testing 50-101 days later. Among 389 individuals who were not boosted at initial testing, the odds of titer < 1000 AU/mL (vs. ≥1000 AU/mL) increased 44% (odds ratio [OR] = 1.44, 95% confidence interval [CI]: 1.18-1.75) for every 30 days since final dose. Among 126 participants boosted before initial testing with no COVID-19 history, 125 (99%) had a value > 2500 AU/ml; 86 (96%) of 90 tested at follow-up and did not develop COVID-19 in the interim remained at that value. One thousand fifty-seven fully vaccinated (330 [29%] boosted at antibody test) individuals participating in the monitoring program were followed to determine COVID-19 status. Individuals with titer value < 1000 AU/mL had twice the risk of COVID-19 as those with >2500 AU/mL (HR = 2.02, 95% CI: 1.28-3.18). Antibody levels decrease postvaccination; boosting increases titer values. While antibody level is not a clear proxy for infection immunity, lower titer values are associated with higher COVID-19 incidence, suggesting increased protection from boosters.

Dynamic Trends and Underlying Factors of COVID-19 Vaccine Booster Hesitancy in Adults: Cross-Sectional Observational Study

BACKGROUND

COVID-19 vaccine hesitancy reduces vaccination rates, which is detrimental to building herd immunity and halting the spread of COVID-19 and its variations. Most researches have simply identified the reasons affecting COVID-19 vaccination reluctance without delving into its dynamics, which makes forecasting future trends difficult.

OBJECTIVE

This study aimed to examine the current COVID-19 vaccine booster hesitancy rate in Chinese adults as well as the dynamics of vaccine hesitancy and its influencing factors. The results of this study will have practical implications for policy responses in mainland China, and effective COVID-19 booster vaccination in specific populations.

METHODS

The web-based survey was completed by creating questionnaires and using a stratified random sampling method to collect information from adults (≥18 years old) among 2556 households in 4 geographical regions of China. We collected sociodemographic information, health status, awareness of COVID-19 and its vaccine, self-perceptions, trust in medical staff and vaccine developers, and so on. The odds ratios and 95% CI for the statistical associations were estimated using logistic regression models.

RESULTS

Overall, 6659 participants (females: n=3540, 53.2%; males: n=3119, 46.8%) responded. In total, 533 (8%; 95% CI 7.4%-8.7%) participants presented a clear hesitancy in receiving the COVID-19 booster vaccination, while 736 (11.1%; 95% CI 10.3%-11.8%) expressed hesitancy in regular booster vaccination. A higher prevalence of vaccine hesitancy in both booster vaccination and regular booster vaccination was observed among participants with a history of allergies, experiencing chronic disease, lower levels of public health prevention measures or susceptibility or benefits or self-efficiency, higher levels of severity or barriers, and lower trust in both medical staff and vaccine developers (P<.05). The females and participants with higher education levels, higher levels of barriers, lower levels of susceptibility, and lower trust in vaccine developers preferred to have attitudinal changes from acceptance to hesitancy, while people with higher education levels, lower self-report health conditions, experiencing chronic disease, history of allergies, and lower trust in medical staff and developers were all positively associated with constant COVID-19 booster hesitancy.

CONCLUSIONS

The prevalence of COVID-19 vaccine booster hesitancy is not high in mainland China. However, there is a slight increment in hesitancy on regular booster vaccination. Conducting targeted information guidance for people with higher education levels and chronic diseases, as well as improving accessibility to booster vaccination and increasing trust in medical staff and vaccine producers may be highly effective in reducing vaccine hesitancy.

Immunogenicity and safety of inactivated SARS-CoV-2 vaccine in haemodialysis patients: a prospective cohort study

End-stage renal disease patients on haemodialysis (HD) have been largely excluded from SARS-CoV-2 vaccine trials due to safety reasons and shown to mount lower responses to vaccination. This study aims to evaluate the immunogenicity and safety of inactivated COVID-19 vaccine among HD patients compared to healthy controls. All subjects who received the primary inactivated COVID-19 vaccination had their blood samples tested 21 days after the second dose. We report the immunogenicity based on anti-RBD IgG titre (IU/mL), the inhibition rate of neutralizing antibodies (NAbs) (%) to RBD, and seroconversion rates. Adverse events were assessed within 30 min and on the 7th day after each dose. Among 75 HD patients and 71 healthy controls, we observed no significant difference in all immunogenicity measures: anti-RBD IgG GMT (277.91 ± 7.13 IU/mL vs. 315.50 ± 3.50 IU/mL, p = 0.645), NAbs inhibition rate (82% [53-96] vs. 84% [39-98], p = 0.654), and seroconversion rates (anti-RBD IgG: 86.7% vs. 85.9%, p = 0.895; NAbs: 45.3% vs. 60.6%, p = 0.065). The number of adverse events is not significantly different between the two groups. The primary inactivated SARS-CoV-2 vaccination elicits an adequate antibody response and can be safely administered in haemodialysis patients.

Longitudinal Observation of Immune Response for 23 Months in COVID-19 Convalescent Patients After Infection and Vaccination

To better understand dynamic changes of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) immune response, a prospective, single-center, cohort study was conducted on longitudinal immune response in 34 COVID-19 convalescent patients over 23 months in Chongqing. Two blood samples from convalescent patients were collected, first sample collected during 10-13 months (M10-13) after infection (pre-SARS-CoV-2 vaccination) and second sample collected during 20-23 months (M20-23) after infection (post-SARS-CoV-2 vaccination). The SARS-CoV-2-specific humoral and cellular immunity were traced by testing total antibody (Ab), anti-nucleocapsid (NP) immunoglobulin M (IgM), anti-NP immunoglobulin G (IgG), and anti-spike (S) IgG Abs, lymphocyte subset count, and Th1 cytokines. Healthy donors (30) were also included in the study as the uninspected healthy controls. Our data showed significant change in mean titer of SARS-CoV-2-specific Ab response from M10-13 to M20-23 included, namely, SARS-CoV-2-specific total Ab as 219 AU/mL increasing to 750.9 AU/mL; anti-NP IgM as 3.5 AU/mL decreasing significantly (p < 0.001) to 0.6 AU/mL; anti-NP IgG as 7.9 AU/mL increasing to 87.1 AU/mL; and anti-S IgG as 499.0 RU/mL increasing to 1,802.3 RU/mL. Our observations suggested that one vaccine dose might have been sufficient for COVID-19 convalescent patients. Larger sample sizes are needed to compare better immune effect of protein subunit vaccine. Besides, compared to healthy donors, patients had decreased CD3+ and CD8+ T lymphocyte counts during two periods. Patients had most cytokines recovered normally within 2 years, but IL-6 level was significantly elevated; however, IL-6 was negatively correlated with IgM and positively correlated with IgG. Changes in cytokines might have been caused by SARS-CoV-2 infection or vaccination. Patients with comorbidities were associated with decreased CD3+ and CD8+ T lymphocytes and lower Ab titers following SARS-CoV-2 vaccination. Vaccination enormously increased humoral immunity beneficial in COVID-19 convalescent patients. Elderly COVID-19 convalescent patients with comorbidities needed more attention.

Humoral immune response to SARS-CoV-2 vaccination in patients with inflammatory bowel disease on immunosuppressive medication: association to serum drug levels and disease type

OBJECTIVES

Immune responses following SARS-CoV-2 vaccination in patients with inflammatory bowel disease (IBD) are not well characterized. The aims of this study were to explore the serological response associated with IBD, and immunosuppressive medications including serum concentrations of biologics and thiopurine metabolites.

MATERIALS AND METHODS

This prospective, observational study included adult patients with ulcerative colitis (UC) and Crohn's disease (CD), and healthy controls. Antibodies to the receptor-binding domain of SARS-CoV-2 spike proteins, and serum concentrations of ongoing biologic and immunomodulatory medications were assessed prior to, and 2-5 weeks after the second vaccine dose. Serologic response was defined as anti-Spike antibodies ≥70 AU/ml.

RESULTS

In 958 IBD patients (380 UC, 578 CD) and 323 healthy controls, the median (Q1; Q3) anti-Spike antibody level (AU/ml) was lower in patients (618 (192; 4370)) compared to controls (3355 (896; 7849)) (p < 0.001). The antibody levels were lower in CD (439 (174; 3304)) compared to UC (1088 (251; 5975)) (p < 0.001). No associations were demonstrated between antibody levels and serum drug concentrations for TNF inhibitor (TNFi), vedolizumab and ustekinumab. Patients receiving TNFi + thiopurines with a subtherapeutic 6-thioguanine nucleotide (6-TGN) level had higher response rate (93%) compared to patients with 6-TGN within the therapeutic range (53%) (p = 0.003). A diagnosis of UC, mRNA-1273 vaccine, and other treatments than TNFi + thiopurines were associated with humoral response.

CONCLUSIONS

Patients with CD had an attenuated humoral response to SARS-COV-2 vaccination as compared to patients with UC. The lack of association between serum levels of biologics and serologic response indicates vaccination regardless of proximity to drug administration.

Antibody Response to COVID-19 Vaccines in Healthcare Workers: Which One is More Successful? Homologous or Heterologous?

Objectives

We aimed to determine the antibody levels created by COVID-19 vaccination in healthcare workers and the factors affecting the antibody response.

Methods

Our research is a single-center, observational study that was prospectively designed and retrospectively analyzed at the beginning of the COVID-19 pandemic, and included 103 healthcare workers who received the three-dose regimen of COVID-19 vaccine. In accordance with the recommendations of the Ministry of Health of Turkey, the first two doses of CoronaVac vaccine were administered routinely, while the booster dose was given as BioNTech or CoronaVac (heterologous or homologous vaccination) depending on the preference of the volunteers. Antibody titers against the SARS-CoV-2 were measured in all individuals at different time points (1 month after the second dose of CoronaVac, before the booster dose [BioNTech or CoronaVac] at the fifth month and one month after the booster dose) with AESKULISA® SARS-CoV-2 S1 IgG (AESKU DIAGNOSTICS, Wendelsheim, Germany).

Results

The mean age was 39.98±11.31 years, 62.1% of whom were women and 54.4% of them were accompanied by comorbid disease. After two doses of CoronaVac, the antibody titer averaged 49.50±33.15 U/mL in the 1st month (antibody seropositivity 86%) and the antibody titer decreased 24.01±33.48 U/mL (antibody seropositivity 49.5%) at 5th month. The mean antibody titer was found 59.73±60.20 U/ml in those who received the booster dose of homologous and 185.07±46.28 U/mL in those who were heterologous (p<0.001). Antibody levels were detected significantly lower after the booster dose of vaccination in patients with comorbidities (p<0.05).

Conclusion

Our study, which reflects the data within the scope of the Turkey Ministry of Health's COVID-19 vaccination program determined that the antibody response after heterologous vaccination is better than in homologous vaccination. Antibody titer level in the 5th month was 50% waned after two doses of inactivated vaccination. It was also shown that factors such as gender, age, body mass index, and smoking did not create a statistically significant difference in homologous and heterologous vaccination, but after the booster dose antibody levels decreased significantly in those with comorbidity.

Relationship between anthropometric and body composition parameters and anti-SARS-CoV-2 specific IgG titers in females vaccinated against COVID-19 according to the heterologous vaccination course: A cohort study

INTRODUCTION

The aim of this cohort study was to evaluate the relationship between anthropometric and body composition parameters and anti-SARS-CoV-2 IgG titers in a group of females who were vaccinated against COVID-19 with two doses of ChAdOx1 vaccine and then boosted with the BNT162b2 vaccine.

MATERIALS AND METHODS

The study group consisted of 63 women. Basic demographic and clinical data were collected. To assess the anti-SARS-CoV-2 immunoglobulin G titers following the vaccination, five blood draws were performed: 1) before the first dose, 2) before the second dose, 3) 14-21 days after the primary vaccination, 4) before the booster, and 5) 21 days after the booster. Blood samples were analyzed using a two-step enzymatic chemiluminescent assay. Body mass index and body composition were evaluated using bioelectrical impedance analysis. To select the most distinguishing parameters and correlations between anthropometric and body composition parameters and anti-SARS-CoV-2 IgG titers, factor analysis using the Principal Component Analysis was conducted.

RESULTS

Sixty-three females (mean age: 46.52 years) who met the inclusion criteria were enrolled. 40 of them (63.50%) participated in the post-booster follow-up. After receiving two doses of the ChAdOx1 vaccine, the study group's anti-SARS-CoV-2 IgG titers were 67.19 ± 77.44 AU/mL (mean ± SD), whereas after receiving a heterologous mRNA booster, the level of anti-SARS-CoV-2 IgG titers was about three-times higher and amounted to 212.64 ± 146.40 AU/mL (mean ± SD). Our data shows that seropositivity, obesity, non-fat-related, and fat-related body composition parameters all had a significant effect on the level of IgG titer after a two-dose vaccination of ChAdOx1. However, only non-fat-related and fat-related body composition parameters had a significant effect on the IgG titer after booster vaccination.

CONCLUSION

COVID-19 infection before the first dose of vaccination is not related to IgG titer after booster administration. Body composition has a significant effect on the production of anti-SARS-CoV-2 IgG after booster vaccination in females.

Transmission and Risk Factors of COVID-19 among Health Care Workers

Coronavirus disease 2019 (COVID-19) poses a significant occupational risk factor to health care workers (HCWs). As in previous events, this occupational risk amplifies and compounds the adverse impact of the pandemic. We conducted a narrative review summarizing risk factors associated with severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) transmission in HCWs. We searched for original observational studies (including case-control, cross-sectional, prospective and retrospective cohorts) using PubMed, Scopus, and Google Scholar. A total of 22 articles were reviewed, including eligible English articles published between April 2020 and May 2022. Job category, work environment, personal protective equipment (PPE) noncompliance, lack of PPE awareness and training, unvaccinated status, and competing community and household exposures were identified as risk factors for SARS-CoV-2 transmission among HCWs. Effective measures to protect HCWs from SARS-CoV-2 need to account for the identified occupational risk factors. Identifying and understanding COVID-19 risk factors among HCWs must be considered a public health priority for policy makers to mitigate occupational and community transmission in current and future epidemics.

Obesity and Viral Infections

The 2019 novel coronavirus disease (COVID-19) triggered a rapidly expanding global pandemic. The presence of obesity in patients with COVID-19 has been established as a risk factor for disease severity, hospital admission, and mortality. Thus, it is imperative those living with obesity be vaccinated against COVID-19. Although there is a timeframe COVID-19 vaccines are efficacious in those living with obesity, more studies need to be conducted to ensure that those long-lasting protection is maintained, as obesity has implications on the immune system.

COVID-19 vaccine coverage, safety, and perceptions among patients with diabetes mellitus in China: a cross-sectional study

Aims

Diabetes mellitus (DM), one of the most common chronic diseases in China, is a risk factor for SARS-COV-2 infection and poor prognosis of COVID-19. The COVID-19 vaccine is one of the key measures to control the pandemic. However, the actual coverage of COVID-19 vaccination and associated factors remain unclear among DM patients in China. We conducted this study to investigate the COVID-19 vaccine coverage, safety, and perceptions among patients with DM in China.

Methods

A cross-sectional study of a sample of 2200 DM patients from 180 tertiary hospitals in China was performed using a questionnaire developed through the Wen Juan Xing survey platform to collect information regarding their coverage, safety, and perceptions of COVID-19 vaccination. A multinomial logistic regression analysis model was performed to determine any independent relationships with COVID-19 vaccination behavior among DM patients.

Results

In total, 1929 (87.7%) DM patients have received at least one dose COVID-19 vaccine, and 271 (12.3%) DM patients were unvaccinated. In addition, 65.2% (n = 1434) were booster vaccinated against COVID-19, while 16.2% (n = 357) were only fully vaccinated and 6.3% (n = 138) were only partially vaccinated. The prevalence of adverse effects after the first dose of vaccine, the second dose of vaccine, and the third dose of vaccine were 6.0%, 6.0%, and 4.3% respectively. Multinomial logistic regression analysis showed that DM patients complicated with immune and inflammatory diseases (partially vaccinated: OR = 0.12; fully vaccinated: OR = 0.11; booster vaccinated: OR = 0.28), diabetic nephropathy (partially vaccinated: OR = 0.23; fully vaccinated: OR = 0.50; booster vaccinated: OR = 0.30), and perceptions on the safety of COVID-19 vaccine (partially vaccinated: OR = 0.44; fully vaccinated: OR = 0.48; booster vaccinated: OR = 0.45) were all associated with the three of vaccination status.

Conclusion

This study showed that higher proportion of COVID-19 vaccine coverage among patients with DM in China. The concern about the safety of the COVID-19 vaccine affected the vaccine behavior in patients with DM. The COVID-19 vaccine was relatively safe for DM patients due to all side effects were self-limiting.

Antibody Response to Inactive SARS-CoV-2 Vaccination in a Cohort of Elderly Patients Living with Obesity

INTRODUCTION

Obesity and aging negatively affect the immune system and host defense mechanisms, increasing vulnerability to and worsening prognosis of infectious diseases, leading to vaccine failure. Our aim was to investigate the antibody response against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike antigens and the risk factors affecting antibody levels in elderly patients living with obesity (PwO) after inactive SARS-CoV-2 vaccine (CoronaVac) administration.

METHODS

One hundred twenty-three consecutive elderly patients with obesity (age ≥65 years, body mass index [BMI] ≥30 kg/m2) and 47 adults with obesity (age 18-64 years, BMI ≥30 kg/m2) admitted between August and November 2021 were enrolled. Seventy-five nonobese elderly people (age ≥65 years, BMI 18.5-29.9 kg/m2) and 105 nonobese adults (age 18-64 years, BMI 18.5-29.9 kg/m2) were recruited from subjects who visited the Vaccination Unit. SARS-CoV-2 spike protein antibody titers were measured in patients with obesity and nonobese controls who received two doses of CoronaVac.

RESULTS

SARS-CoV-2 levels of patients with obesity were found to be significantly lower than those of nonobese elderly individuals who had non-prior infection. There was no difference in SARS-CoV-2 levels between patients with obesity and nonobese individuals with prior infection. Age and SARS-CoV-2 level were found to be highly correlated in the correlation analysis in the group of elderly individuals (r: -0.184). In multivariate regression analysis, when SARS-CoV-2 immunoglobulin class G (IgG) was regressed on age, sex, BMI, type 2 diabetes mellitus, and hypertension (HT), HT was found to be an independent factor of the SARS-CoV-2 level (β: -2,730).

CONCLUSION

In the non-prior infection group, elderly patients with obesity generated significantly reduced antibody titers against SARS-CoV-2 spike antigen after CoronaVac vaccine compared to nonobese people. It is anticipated that the results obtained will provide invaluable information about SARS-CoV-2 vaccination strategies in this vulnerable population. Antibody titers may be measured, and booster doses should be delivered accordingly in elderly PwO for optimal protection.

Association between Overweight/Obesity and the Safety and Efficacy of COVID-19 Vaccination: A Systematic Review

OBJECTIVE

The objective of this study was to appraise the interrelation between overweight/obesity and the safety and efficacy of COVID-19 vaccination by synthesizing the currently available evidence.

METHODS

A systematic review of published studies on the safety and efficacy of the COVID-19 vaccine in people who were overweight or obese was conducted. Databases including Embase, Medline Epub (Ovid), PsychInfo (Ovid), Web of Science, PubMed, CINAHL, and Google Scholar were searched to identify relevant studies. The databases of the Centers for Disease Control (CDC) and World Health Organization (WHO) were also searched for relevant unpublished and gray literature.

RESULTS

Fifteen studies were included in the review. All the included studies used observational study designs; there were ten cohort studies and five cross-sectional studies. The sample size of these studies ranged from 21 to 9,171,524. Thirteen studies reported using BNT162b2 (Pfizer-BioNTech, USA), four reported using ChAdOx-nCov19 (AstraZeneca, U.K), two were reported using CoronaVac (Sinovac, China), and two were reported using mRNA1273 (Moderna, USA). The efficacy and safety of COVID-19 vaccines have been extensively studied in individuals with overweight/obesity. Most studies have shown that the humoral response decreases with increasing BMI. The available evidence does not conclusively indicate that these vaccines are generally safe in this population.

CONCLUSION

While the efficacy of the COVID-19 vaccine may be less than ideal in people who are overweight or obese, it does not mean that obese people should not be vaccinated, as the vaccine can still provide some protection. There is a lack of evidence for conclusions to be drawn about the safety of the vaccine in the population. This study calls on health professionals, policymakers, caregivers, and all other stakeholders to focus on monitoring the possible adverse effects of injections in overweight/obese people.

Association of fat-soluble vitamins (A, D, and E) status with humoral immune response to COVID-19 inactivated vaccination

Background

Fat-soluble vitamins (A, D, and E) are essential for the proper functioning of the immune system and are of central importance for infection risk in humans. Vitamins A, D, and E have been reported to be associated with the immune response following vaccination; however, their effects on the immune response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination remain unknown.

Methods

We measured the neutralizing antibody titers against wild type and omicron within 98 days after the third homologous boosting shot of inactivated SARS-CoV-2 vaccine (BBIBP-CorV or CoronaVac) in 141 healthy adults in a prospective, open-label study. High-performance liquid chromatography-tandem mass spectroscopy was used to determine the concentrations of plasma vitamins A, D, and E.

Results

We found that the anti-wide-type virus and anti-omicron variant antibody levels significantly increased compared with baseline antibody levels (P < 0.001) after the third vaccination. 25(OH)D₃ was significantly negatively associated with the baseline anti-wide-type virus antibody concentrations [beta (95% CI) = -0.331 (-0.659 ~ -0.003)] after adjusting for covariates. A potentially similar association was also observed on day 98 after the third vaccination [beta (95% CI) = -0.317 (-0.641 ~ 0.007)]. After adjusting for covariates, we also found that 25(OH)D₃ was significantly negatively associated with the seropositivity of the anti-omicron variant antibody at day 98 after the third vaccination [OR (95% CI) = 0.940 (0.883 ~ 0.996)]. The association between plasma 25(OH)D₃ with anti-wild-type virus antibody levels and seropositivity of anti-omicron variant antibodies were persistent in subgroup analyses. We observed no association between retinol/α-tocopherol and anti-wide-type virus antibody levels or anti-omicron variant antibody seropositive in our study.

Conclusion

The third inactivated SARS-CoV-2 vaccination significantly improved the ability of anti-SARS-CoV-2 infection in the human body. Higher vitamin D concentrations could significantly decrease the anti-wide-type virus-neutralizing antibody titers and anti-omicron variant antibody seropositive rate after the inactivated SARS-CoV-2 vaccination in people with adequate levels of vitamin D, better immune status, and stronger immune response; further studies comprising large cohorts of patients with different nutritional status are warranted to verify our results.

Humoral and Cellular Response and Associated Variables Nine Months following BNT162b2 Vaccination in Healthcare Workers

In this study, we aimed to illustrate the trajectory of humoral and cellular immunity nine months after primary vaccination with the BNT162b2 mRNA vaccine among 189 healthcare workers (HCWs). Additionally, we endeavored to identify correlations between immunity parameters and a number of common variables and comorbidities. A total of 189 healthcare workers (HCWs), vaccinated against COVID-19, were finally included in the study. All of the subjects had received two doses of the BNT162b2 vaccine; had undergone antibody tests one, four and nine months post-vaccination; and had completed a medical questionnaire. Further samples taken at nine months were tested for cellular immunity. No participants had evidence of COVID-19 infection pre- or post-vaccination. An anti-S1 receptor binding domain (RBD) antibody assay was used to assess humoral response, and cellular immunity was estimated with an INF-γ release assay (IGRA). Statistical analysis was performed using STATA. We report a statistically significant antibody drop over time. Being above the age of 40 or a smoker reduces the rise of antibodies by 37% and 28%, respectively. More than half of the participants did not demonstrate T-cell activation at nine months. Female gender and antibody levels at four months predispose detection of cellular immunity at nine months post-immunization. This study furthers the qualitative, quantitative, and temporal understanding of the immune response to the BNT162b2 mRNA vaccine and the effect of correlated factors.

Validation of N Protein Antibodies to Diagnose Previous SARS-CoV-2 Infection in a Large Cohort of Healthcare Workers: Use of Roche Elecsys® Immunoassay in the S Protein Vaccination Era

The aim of this study was to validate the detection of anti-nucleocapsid protein (N protein) antibodies for the diagnosis of SARS-CoV-2 infection in light of the fact that most COVID-19 vaccines use the spike (S) protein as the antigen. Here, 3550 healthcare workers (HCWs) were enrolled from May 2020 (when no S protein vaccines were available). We defined SARS-CoV-2 infection if HCWs were found to be positive by RT-PCR or found to be positive in at least two different serological immunoassays. Serum samples from Biobanc I3PT-CERCA were analyzed by Roche Elecsys^® (N protein) and Vircell IgG (N and S proteins) immunoassays. Discordant samples were reanalyzed with other commercial immunoassays. Roche Elecsys^® showed the positivity of 539 (15.2%) HCWs, 664 (18.7%) were found to be positive by Vircell IgG immunoassays, and 164 samples (4.6%) showed discrepant results. According to our SARS-CoV-2 infection criteria, 563 HCWs had SARS-CoV-2 infection. The Roche Elecsys^® immunoassay has a sensitivity, specificity, accuracy, and concordance with the presence of infection of 94.7%, 99.8%, 99.3%, and 0.96, respectively. Similar results were observed in a validation cohort of vaccinated HCWs. We conclude that the Roche Elecsys^® SARS-CoV-2 N protein immunoassay demonstrated good performance in diagnosing previous SARS-CoV-2 infection in a large cohort of HCWs.

Factors affecting the immunogenicity of influenza vaccines in human

BACKGROUND

The influenza viruses pose a threat to human health and medical services, and vaccination is an important way to prevent infection. However, the effectiveness of influenza vaccines is affected by various aspects. This study aimed to explore factors related to the immune response to influenza vaccines.

METHODS

The study was conducted from September 2019 to September 2021, and a total of 593 volunteers were recruited from the Center for Disease Control and Prevention in 3 provinces in China. The hemagglutination inhibition assay was used to measure antibody levels. The Chi-square test, multivariable logistic regression analysis, and sum-rank test were used to analyze the factors associated with influenza vaccine immune response.

RESULTS

The Chi-square test showed that seroconversion rates and response rate were associated with age group, vaccination history, chronic conditions, the frequency of colds, and region (P < 0.05). The multivariable logistic regression analysis showed that age was an important factor that affected participants' seroconversion rates for A/H1N1, A/H3N2, B/Victoria, and response status (18-64 vs. ≤5: OR = 2.77, P < 0.001; ≥65 vs. ≤5: OR = 0.38, P = 0.01; 18-64 vs. ≤5: OR = 2.64, P = 0.03). Vaccination history was also an affecting factor for A/H1N1, B/Victoria, and response status (yes vs. no: OR = 0.4 / 0.44 / 0.25, P < 0.001). The frequency of colds and chronic conditions were also affecting factors for participants' seroconversion rates and response levels to different degrees. The sum-rank test showed that the fold changes for A/H1N1, B/Victoria, and B/Yamagata were associated with age group and vaccination history (P < 0.01). The fold changes for A/H3N2 were associated with the frequency of colds (P < 0.05), and those for B/Victoria were associated with gender and chronic conditions (P < 0.05).

CONCLUSIONS

Vaccination history, age, health condition, and frequency of colds were important factors affecting the seroconversion rate of the influenza vaccine in human. There is a need for developing optimized vaccination strategies for vulnerable groups to improve the efficacy of influenza vaccines in human.

Smoking cessation and vaccination

A significant proportion of COPD patients (∼40%) continue smoking despite knowing that they have the disease. Smokers with COPD exhibit higher levels of nicotine dependence, and have lower self-efficacy and self-esteem, which affects their ability to quit smoking. Treatment should be adapted to the needs of individual patients with different levels of tobacco dependence. The combination of counselling plus pharmacotherapy is the most effective cessation treatment for COPD. In patients with severe COPD, varenicline and bupropion have been shown to have the highest abstinence rates compared with nicotine replacement therapy. There is a lack of evidence to support that smoking cessation reduction or harm reduction strategies have benefits in COPD patients. The long-term efficacy and safety of electronic cigarettes for smoking cessation need to be evaluated in high-risk populations; therefore, it is not possible to recommend their use for smoking cessation in COPD. Future studies with the new generation of nicotine vaccines are necessary to determine their effectiveness in smokers in general and in COPD patients.

Elicitation of potent neutralizing antibodies in obese mice by ISA 51-adjuvanted SARS-CoV-2 spike RBD-Fc vaccine

Vaccination is considered to be the most effective countermeasure to prevent and combat the global health threats of COVID-19. People with obesity are at a greater risk of hospitalization, life-threatening illness, and adverse outcomes after having COVID-19. Therefore, a safe and effective COVID-19 vaccine for obese individuals is urgently needed. In the study, the vaccine composed of the ISA 51 adjuvant and the SARS-CoV-2 spike (S) receptor-binding domain (RBD) in conjugation with the human IgG1 Fc fragment (named as ISA 51-adjuvanted RBD-Fc vaccine) was developed and inoculated in the regular chow diet (RCD) lean mice and the high-fat diet (HFD)-induced obese mice. The S protein-specific IgG titers were largely induced in an increasing manner along with three doses of ISA 51-adjuvanted RBD-Fc vaccine without causing any harmful side effect. In the HFD mice, the S protein-specific IgG titers can be quickly observed 2 weeks post the first inoculation. The antisera elicited by the ISA 51-adjuvanted RBD-Fc vaccine in the RCD and HFD mice exhibited potent SARS-CoV-2 neutralizing activities in the plaque reduction neutralization test (PRNT) assays and showed similar specificity for recognizing the key residues in the RBD which were involved in interacting with angiotensin-converting enzyme 2 (ACE2) receptor. The immune efficacy of the ISA 51-adjuvanted RBD-Fc vaccine in the HFD mice can be sustainably maintained with the PRNT50 values of 1.80-1.91×10^-3 for at least 8 weeks post the third inoculation. Collectively, the RBD-Fc-based immunogen and the ISA 51-adjuvanted formulation can be developed as an effective COVID-19 vaccine for obese individuals. KEY POINTS: • The ISA 51-adjuvanted RBD-Fc vaccine can induce potent SARS-CoV-2 neutralizing antibodies in the obese mouse • The antibodies elicited by the ISA 51-adjuvanted RBD-Fc vaccine can bind to the key RBD residues involved in interacting with ACE2 • The immune efficacy of the ISA 51-adjuvanted RBD-Fc vaccine can be sustainably maintained for at least 8 weeks post the third inoculation.

A meta-analysis of the associations between insufficient sleep duration and antibody response to vaccination

Vaccination is a major strategy to control a viral pandemic. Simple behavioral interventions that might boost vaccine responses have yet to be identified. We conducted meta-analyses to summarize the evidence linking the amount of sleep obtained in the days surrounding vaccination to antibody response in healthy adults. Authors of the included studies provided the information needed to accurately estimate the pooled effect size (ES) and 95% confidence intervals (95% CI) and to examine sex differences.^{1,2,3,4,5,6,7} The association between self-reported short sleep (<6 h/night) and reduced vaccine response did not reach our pre-defined statistical significant criteria (total n = 504, ages 18-85; overall ES [95% CI] = 0.29 [-0.04, 0.63]). Objectively assessed short sleep was associated with a robust decrease in antibody response (total n = 304, ages 18-60; overall ES [95% CI] = 0.79 [0.40, 1.18]). In men, the pooled ES was large (overall ES [95% CI] = 0.93 [0.54, 1.33]), whereas it did not reach significance in women (overall ES [95% CI] = 0.42 [-0.49, 1.32]). These results provide evidence that insufficient sleep duration substantially decreases the response to anti-viral vaccination and suggests that achieving adequate amount of sleep during the days surrounding vaccination may enhance and prolong the humoral response. Large-scale well-controlled studies are urgently needed to define (1) the window of time around inoculation when optimizing sleep duration is most beneficial, (2) the causes of the sex disparity in the impact of sleep on the response, and (3) the amount of sleep needed to protect the response.