Effectiveness and Waning of Protection With Different SARS-CoV-2 Primary and Booster Vaccines During the Delta Pandemic Wave in 2021 in Hungary (HUN-VE 3 Study)

Vaccine effectiveness of JCOVDEN single-dose against COVID-19 hospitalisation in Europe: An id.DRIVE test-negative case-control study

BACKGROUND

JCOVDEN (Ad26.COV2.S), a viral-vector vaccine, was granted conditional marketing authorisation in the European Union for the prevention of COVID-19 in early 2021. We present JCOVDEN single-dose vaccine effectiveness (VE) estimates against COVID-19 hospitalisation.

METHODS

The id.DRIVE (previously COVIDRIVE) COVID-19 VE study is an ongoing European non-interventional, multi-centre study with a test-negative case-control design. Study participants were adults ≥ 18 years old, hospitalised with severe acute respiratory infection between 1 May 2021 and 28 February 2023. Estimated as a single measure over the entire study period, VE was stratified by risk group, time since vaccination intervals (14 days-12 weeks, 12-to-25 weeks, 25-to-52 weeks, >52 weeks), SARS-CoV-2 variant and calendar time categories. All estimates were adjusted for symptom-onset date, age, sex, and number of pre-defined chronic conditions.

RESULTS

Overall, VE was 55.6 % (95 % CI 23.6; 74.2) for a median time since vaccination of 146 days. For 18- to 49-year-olds, VE was 61.6 % (95 % CI 16.2; 82.4), 57.7 % (95 % CI 3.4; 81.5) for 50- to-64-years-olds, and 40.8 % (95 % CI -6.0; 66.9) for ≥ 65-year-olds. Most precise estimates were obtained for time since vaccination 12-to- 25-week interval (59.2 % [95 % CI 25.0; 77.8]) and for the calendar time period 1 Aug 2021 -30 Nov 2021 (Delta predominant; 51.2 % [95 % CI 21.7; 69.6]).

CONCLUSION

The JCOVDEN single-dose protected against COVID-19 hospitalisation. It is effective for at least six months, with VE estimates comparatively lower in the older age groups. Results had low to medium levels of certainty and are to be interpreted with caution.

Real-world evidence of remdesivir in formerly hospitalized COVID-19 patients: patient-reported and functional outcomes

BACKGROUND

Post-COVID condition (PCC) is characterized by persisting symptoms after the resolution of acute COVID-19. Remdesivir (RDV), a broad-spectrum antiviral drug, has been widely used in patients hospitalized with COVID-19 requiring oxygen therapy. We aimed to evaluate the effects of RDV on PCC by assessing patient-reported and functional outcomes.

METHODS

We used the data from a single-center registry, including formerly hospitalized post-COVID patients (N = 293). Propensity score matching (PSM) was used (16 criteria, 1:1 ratio) to obtain two comparable groups: those who received standard-of-care (SOC, N = 94) and those treated with RDV in addition to SOC (SOC + RDV, N = 94). Primary outcomes were asymptomatic status and at least 50% symptom score reduction at post-COVID follow-up. Secondary outcomes included results of pulmonary function (PF) tests, 6-minute walk test (6MWT), and quality-of-life (QoL) questionnaires.

RESULTS

After PSM, baseline patient characteristics showed no significant differences between the two groups. Most patients were still symptomatic (60% vs. 66%). In the SOC + RDV group, the use of oxygen supplementation (94 vs. 80%, p = 0.005) and steroids (97 vs. 88%, p = 0.027) during infection were higher, while patients presented at their post-COVID visits earlier (median 68 vs. 97 days, p = 0.003). Complete or at least 50% symptom resolution were reported at a significantly earlier stage after infection in the SOC + RDV group compared to the SOC group (multivariable-adjusted HR = 2.28, 95% CI = 1.33-3.92, p = 0.003; and HR = 2.08, 95% CI = 1.43-3.02, p < 0.001; respectively). In the SOC + RDV group, fewer patients experienced sleep disturbances at PCC, and sleep-related questionnaires (Pittsburg Sleep Quality Index, PSQI) results showed significantly better sleep quality (14 vs. 27% and 5.9 vs. 7.7 points, respectively). There were no notable differences in results of PF tests, 6MWT, and other QoL questionnaires.

CONCLUSION

In this propensity score matched cohort, the use of RDV was associated with earlier patient reported symptom resolution during the PCC period, while there were no notable differences in functional outcomes. Our results indicate a possible beneficial effect of RDV in terms of faster symptom resolution after COVID19 infection.

Assessing COVID-19 Vaccine Effectiveness and Risk Factors for Severe Outcomes through Machine Learning Techniques: A Real-World Data Study in Andalusia, Spain

BACKGROUND

COVID-19 vaccination has become a pivotal global strategy in managing the pandemic. Despite COVID-19 no longer being classified as a Public Health Emergency of International Concern, the virus continues affecting people worldwide. This study aimed to evaluate risk factors and vaccine effectiveness on COVID-19-related hospital admissions, intensive care unit (ICU) admission and mortality within the Andalusian population throughout the pandemic.

METHODS

From March 2020 to April 2022, 671,229 individuals, out of 9,283,485 with electronic health records in Andalusia, experienced SARS-CoV-2 infection and were included in the analysis. Data on demographics, medical history, vaccine administration, and hospitalization records were collected. Associations between medical history, COVID-19 vaccines, and COVID-19 outcomes were assessed.

RESULTS

Our study identified 48,196 hospital admissions, 5,057 ICU admissions, and 11,289 deaths linked to COVID-19. Age, male sex, and chronic diseases were identified as risk factors, while the COVID-19 vaccine demonstrated protective effects, although with reduced effectiveness during the omicron variant period. However, the risk for these outcomes increased over time after receiving the last vaccine dose, particularly after six months, especially among those aged 60 or older.

CONCLUSION

The global health challenge of COVID-19 persists, marked by emerging variants with higher virulence and severity, particularly among the unvaccinated and those beyond six months post-vaccination, especially those aged 60 and above. These findings highlight the need for robust surveillance systems targeting new variants and administering booster doses, particularly for individuals aged 60 or older with underlying health conditions, to mitigate the global burden of COVID-19.

Genomic characteristics, disease outcome and heterologous vaccine effectiveness among cases with SARS CoV-2 infection

BACKGROUND

In the pursuit of global health security, continuous monitoring of vaccine effectiveness across various viral strains emerges as a crucial imperative. The emergence of SARS-CoV-2 major variants of concern (VOCs), including Alpha, Beta, Delta, and Omicron, has added complexity to the COVID-19 vaccination landscape.

OBJECTIVES

To assess illness severity, evaluate vaccine efficacy across varying doses and types, and determine effectiveness against major VOCs within the population.

METHODS

This retrospective cohort study, conducted in Abu Dhabi, United Arab Emirates, focuses on a cohort of 44,073 SARS-CoV-2 positive cases from February 2021 to May 2022, dominated by the Delta and Omicron variants. The study employed a nested case-control design, analyzing hospital admissions for confirmed SARS-CoV-2 infection.

RESULTS

Vaccine effectiveness was higher among heterologus-boosted individuals at 87% (95% CI:79%-93%) compared to homologus-boosted individuals at 59% (95% CI: 48%-68%) and fully vaccinated, non-boosted adults at 53% (95% CI: 46%-59%). These findings highlight the importance of heterologous boosting, particularly against rapidly evolving viral variants, offering valuable insights for refining pandemic response strategies.

CONCLUSION

The study underscores the critical need for ongoing assessment and adaptation of vaccination strategies to the evolving viral landscape.

Investigating the FLiRT variants of COVID-19: Is it an emerging concern?

The ongoing COVID-19 pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has led to multiple waves of infections globally. As the virus continues to evolve, new variants have emerged, some with concerning changes in transmissibility and virulence. Among these variants, the "FLiRT Variants" have recently gained attention due to their potential to alter the dynamics of transmission and disease severity. According to the Infectious Disease Society of America, the nickname 'FLiRT' is based on the technical names for their mutations. The FLiRT variants, particularly KP.2, seem to exhibit heightened transmissibility in comparison to earlier Omicron sub-variants. Additionally, they demonstrate a capacity to evade immunity conferred by prior infection and vaccines, although the full extent of this evasion is still being investigated. In this article, we review the characteristics of the FLiRT variants, including their genetic mutations, epidemiological features, potential impact on public health measures, and implications for vaccine efficacy. We also discuss strategies for surveillance, prevention, and mitigation efforts to control the spread of this variant and mitigate its impact on global health.

Primary series COVID-19 vaccine effectiveness among health care workers in the country of Georgia, March-December 2021

BACKGROUND

Healthcare workers (HCWs) have suffered considerable morbidity and mortality during the COVID-19 pandemic. Few data on COVID-19 vaccine effectiveness (VE) are available from middle-income countries in the WHO European Region. We evaluated primary series COVID-19 VE against laboratory-confirmed COVID-19 among HCWs in Georgia.

METHODS

HCWs in six hospitals in Georgia were invited to enroll in a prospective cohort study conducted during March 19-December 5, 2021. Participants completed weekly symptom questionnaires. Symptomatic HCWs were tested by RT-PCR and/or rapid antigen test (RAT), and participants were routinely tested for SARS-CoV-2 by RT-PCR or RAT, regardless of symptoms. Serology was collected at enrolment, and quarterly thereafter, and tested by electrochemiluminescence immunoassay for SARS-CoV-2 antibodies. We defined primary series vaccination as two doses of COVID-19 vaccine received ≥14 days before symptom onset. We estimated VE as (1-hazard ratio)*100 using a Cox proportional hazards model with vaccination status as a time-varying covariate. Estimates were adjusted by potential confounders that changed the VE estimate by more than 5%, according to the change-in-estimate approach.

RESULTS

Overall, 1561/3849 (41%) eligible HCWs enrolled and were included in the analysis. The median age was 40 (IQR: 30-53), 1318 (84%) were female, and 1003 (64%) had laboratory evidence of prior SARS-Cov-2 infection. At enrolment, 1300 (83%) were unvaccinated; By study end, 1082 (62%) had completed a primary vaccine series (69% BNT162b2 (Pfizer-BioNTech); 22% BBIBP-CorV (Sinopharm); 9% other). During the study period, 191(12%) participants had a new PCR- or RAT-confirmed symptomatic SARS-CoV-2 infection. VE against PCR- or RAT- confirmed symptomatic SARS-CoV-2 infection was 58% (95%CI: 41; 70) for all primary series vaccinations, 68% (95%CI: 51; 79) for BNT162b2, and 40% (95%CI: 1; 64) for BBIBP-CorV vaccines. Among previously infected HCWs, VE was 58% (95%CI: 11; 80). VE against medically attended COVID-19 was 52% (95%CI: 28; 68), and VE against hospitalization was 69% (95% CI: 36; 85). During the period of predominant Delta variant circulation (July-December 2021), VE against symptomatic COVID-19 was 52% (95%CI: 30; 66).

CONCLUSIONS

Primary series vaccination with BNT162b2 and BBIBP-CorV was effective at preventing COVID-19 among HCWs, most of whom had previous infection, during a period of mainly Delta circulation. Our results support the utility of COVID-19 primary vaccine series, and the importance of increasing coverage, even among previously infected individuals.

Estimation of COVID-19 vaccine effectiveness against infections and severe outcomes using routine surveillance data in Kosovo, July-September 2021

BACKGROUND

COVID-19 vaccines have proven effective against severe outcomes in many settings, yet vaccine effectiveness (VE) estimates remain lacking for Kosovo. We aimed to estimate VE against COVID-19 infections, hospitalisations, and deaths for one and two vaccine doses during the fourth pandemic wave in July-September 2021, the period when vaccination initially became widely available.

METHODS

We analysed routine surveillance data to define cases and vaccination status as partially (one dose) or completely (two doses) vaccinated. We used the screening method to calculate the proportion of cases with the outcomes vaccinated (PCV). The proportion of the population vaccinated (PPV) was based on numbers vaccinated and the Kosovo population estimate on 30/09/2021.

RESULTS

Between July-September 2021, 51,804 COVID-19 cases were reported in Kosovo with 9.3% of cases partially and 3.4% completely vaccinated. Estimated vaccine effectiveness for one dose was 93.1% (95%CI:92.9-93.2%) for infections, 90.3% (95%CI:88.8-91.7%) for hospitalisations, and 90.3% (95%CI:88.4-92.1%) for deaths. Estimated vaccine effectiveness for two doses was 97.8% (95%CI:97.6-97.9%) for infections, 94.5% (95%CI:93.3-95.6%) for hospitalisations, and 94.2% (95%CI: 93.7-96.5%) for deaths.

CONCLUSIONS

This study provides real-world evidence for COVID-19 vaccine effectiveness in Kosovo using routine administrative data sources and the screening method. COVID-19 vaccine effectiveness against infections and severe outcomes in Kosovo was higher with two vaccine doses than one dose, which is in accordance with findings from other study designs and settings. Using the screening method in our study reflects an important initial methodology for estimating vaccine effectiveness with routine surveillance that may be particularly important for low- and middle-income settings with less robust surveillance systems or fewer opportunities to conduct more robust vaccine effectiveness study designs.

Comparative Effectiveness of mRNA-1273 and BNT162b2 COVID-19 Vaccines Among Older Adults: Systematic Literature Review and Meta-Analysis Using the GRADE Framework

INTRODUCTION

The mRNA vaccines mRNA-1273 and BNT162b2 demonstrated high efficacy against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in phase 3 clinical trials, including among older adults. To inform coronavirus disease 2019 (COVID-19) vaccine selection, this systematic literature review (SLR) and meta-analysis assessed the comparative effectiveness of mRNA-1273 versus BNT162b2 in older adults.

METHODS

We systematically searched for relevant studies reporting COVID-19 outcomes with mRNA vaccines in older adults aged ≥ 50 years by first cross-checking relevant published SLRs. Based on the cutoff date from a previous similar SLR, we then searched the WHO COVID-19 Research Database for relevant articles published between April 9, 2022, and June 2, 2023. Outcomes of interest were SARS-CoV-2 infection, symptomatic SARS-CoV-2 infection, severe SARS-CoV-2 infection, COVID-19-related hospitalization, and COVID-19-related death following ≥ 2 vaccine doses. Random effects meta-analysis models were used to pool risk ratios (RRs) across studies. Heterogeneity was evaluated using chi-square testing. Evidence certainty was assessed per GRADE framework.

RESULTS

Twenty-four non-randomized real-world studies reporting clinical outcomes with mRNA vaccines in individuals aged ≥ 50 years were included in the meta-analysis. Vaccination with mRNA-1273 was associated with significantly lower risk of SARS-CoV-2 infection (RR 0.72 [95% confidence interval (CI) 0.64‒0.80]), symptomatic SARS-CoV-2 infection (RR 0.72 [95% CI 0.62‒0.83]), severe SARS-CoV-2 infection (RR 0.67 [95% CI 0.57‒0.78]), and COVID-19-related hospitalization (RR 0.65 [95% CI 0.53‒0.79]) but not COVID-19-related death (RR 0.80 [95% CI 0.64‒1.00]) compared with BNT162b2. There was considerable heterogeneity between studies for all outcomes (I2 > 75%) except death (I2 = 0%). Multiple subgroup and sensitivity analyses excluding specific studies generally demonstrated consistent results. Certainty of evidence across outcomes was rated as low (type 3) or very low (type 4), reflecting the lack of randomized controlled trial data.

CONCLUSION

Meta-analysis of 24 observational studies demonstrated significantly lower risk of asymptomatic, symptomatic, and severe infections and hospitalizations with the mRNA-1273 versus BNT162b2 vaccine in older adults aged ≥ 50 years.

The effect of COVID-19 vaccination status on all-cause mortality in patients hospitalised with COVID-19 in Hungary during the delta wave of the pandemic

The high mortality of patients with coronavirus disease 2019 (COVID-19) is effectively reduced by vaccination. However, the effect of vaccination on mortality among hospitalised patients is under-researched. Thus, we investigated the effect of a full primary or an additional booster vaccination on in-hospital mortality among patients hospitalised with COVID-19 during the delta wave of the pandemic. This retrospective cohort included all patients (n = 430) admitted with COVID-19 at Semmelweis University Department of Medicine and Oncology in 01/OCT/2021-15/DEC/2021. Logistic regression models were built with COVID-19-associated in-hospital/30 day-mortality as outcome with hierarchical entry of predictors of vaccination, vaccination status, measures of disease severity, and chronic comorbidities. Deceased COVID-19 patients were older and presented more frequently with cardiac complications, chronic kidney disease, and active malignancy, as well as higher levels of inflammatory markers, serum creatinine, and lower albumin compared to surviving patients (all p < 0.05). However, the rates of vaccination were similar (52-55%) in both groups. Based on the fully adjusted model, there was a linear decrease of mortality from no/incomplete vaccination (ref) through full primary (OR 0.69, 95% CI: 0.39-1.23) to booster vaccination (OR 0.31, 95% CI 0.13-0.72, p = 0.006). Although unadjusted mortality was similar among vaccinated and unvaccinated patients, this was explained by differences in comorbidities and disease severity. In adjusted models, a full primary and especially a booster vaccination improved survival of patients hospitalised with COVID-19 during the delta wave of the pandemic. Our findings may improve the quality of patient provider discussions at the time of admission.

Vaccine Effectiveness against SARS-CoV-2 Infection during the Circulation of Alpha, Delta, or Omicron Variants: A Retrospective Cohort Study in a Tertiary Hospital in Serbia

The COVID-19 pandemic prompted rapid vaccine development and deployment worldwide. Despite widespread vaccination efforts, understanding the effectiveness of vaccines in hospitalized patients remains a critical concern. This retrospective cohort study, conducted at a tertiary healthcare centre in Serbia, tracked patients hospitalized during different waves of COVID-19 variants-Alpha, Delta, and Omicron. Data collection included demographics, comorbidities, symptoms, and vaccination status. Among 3593 patients, those with prior exposure to COVID-19 cases or hospital treatment showed higher positivity rates. Symptom prevalence varied across waves, with coughs persisting. Patients without chronic diseases were more frequent among those testing negative. Vaccine effectiveness varied, with Sinopharm demonstrating a 45.6% effectiveness initially and Pfizer-BioNTech showing an effectiveness of up to 74.8% within 0-84 days after the second dose. Mixed-dose strategies, notably Sinopharm as a primary dose followed by a Pfizer-BioNTech booster, suggested increased protection. Despite substantial vaccination availability, a significant portion of hospitalized patients remained unvaccinated. This study underscores the dynamic nature of vaccine effectiveness and advocates for booster strategies to address evolving challenges in combating COVID-19, particularly in hospitalized patients.

Effectiveness of SARS-CoV-2 primary vaccines and boosters in patients with type 2 diabetes mellitus in Hungary (HUN-VE 4 Study)

INTRODUCTION

Type 2 diabetes mellitus is a risk factor for severe COVID-19 infection and is associated with increased risk of complications. The present study aimed to investigate effectiveness and persistence of different COVID vaccines in persons with or without diabetes during the Delta wave in Hungary.

RESEARCH DESIGN AND METHODS

Data sources were the national COVID-19 registry data from the National Public Health Center and the National Health Insurance Fund on the total Hungarian population. The adjusted incidence rate ratios and corresponding 95% CIs were derived from a mixed-effect negative binomial regression model.

RESULTS

A population of 672 240 cases with type 2 diabetes and a control group of 2 974 102 non-diabetic persons free from chronic diseases participated. Unvaccinated elderly persons with diabetes had 2.68 (95% CI 2.47 to 2.91) times higher COVID-19-related mortality rate as the 'healthy' controls. Primary immunization effectively equalized the risk of COVID-19 mortality between the two groups. Vaccine effectiveness declined over time, but the booster restored the effectiveness against mortality to over 90%. The adjusted vaccine effectiveness of the primary Pfizer-BioNTech against infection in the 14-120 days of postvaccination period was 71.6 (95% CI 66.3 to 76.1)% in patients aged 65-100 years with type 2 diabetes and 64.52 (95% CI 59.2 to 69.2)% in the controls. Overall, the effectiveness tended to be higher in individuals with diabetes than in controls. The booster vaccines could restore vaccine effectiveness to over 80% concerning risk of infection (eg, patients with diabetes aged 65-100 years: 89.1 (88.1-89.9)% with Pfizer-on-Pfizer, controls 65-100 years old: 86.9 (85.8-88.0)% with Pfizer-on-Pfizer, or patients with diabetes aged 65-100 years: 88.3 (87.2-89.2)% with Pfizer-on-Sinopharm, controls 65-100 years old: 87.8 (86.8-88.7)% with Pfizer-on-Sinopharm).

CONCLUSIONS

Our data suggest that people with type 2 diabetes may have even higher health gain when getting vaccinated as compared with non-diabetic persons, eliminating the marked, COVID-19-related excess risk of this population. Boosters could restore protection.

Comparative analysis of antibody responses to BNT162b2, ChAdOx1, and CoronaVac vaccines in the Albanian population over the pandemic years 2021 to 2022

This repeated cross-sectional study with two independent sample populations compared the antibody response to severe acute respiratory syndrome coronavirus 2 vaccines in Albania in July-August 2021 and 2022. In 2021, it found higher anti-spike-1 seropositivity and antibody levels in fully vaccinated individuals, especially with BNT162b2 and ChAdOx1 and to a lesser degree with CoronaVac. By 2022, all single-dose recipients showed high antibody responses, suggesting natural infection-enhanced immunity. The study indicates a significant evolution in the antibody response to different coronavirus disease 2019 vaccines and suggests that a single vaccine dose, coupled with natural infection, might suffice to maintain adequate immunity levels in an endemic scenario.

Long-Term SARS-CoV-2-Specific Humoral and T Cell Responses after the BNT162b2 or BBIBP-CorV Booster and the Incidence of Breakthrough Infections among Healthcare Workers

The effectiveness of COVID-19 vaccines developed against the original virus strain deteriorated noticeably in efficacy against the Omicron variant (B.1.1.529). Moreover, the immunity developed after vaccination or due to natural infection rapidly waned. In the present study, covering this period, we summarize the incidence of breakthrough infections among healthcare workers (HCWs) with respect to administration of the three vaccine doses. Additionally, we evaluate the long-term SARS-CoV-2-specific humoral and T cell responses at two different time points: six and twelve months after receipt of the third (booster) dose. The spike-protein-specific antibody levels and the quantity of structural-protein-specific T cells were evaluated at these time points and compared with the values measured earlier, 14 days after the booster vaccination. The study participants were categorized into two cohorts: Members of the first cohort received a two-dose BNT162b2 mRNA-based vaccine regimen, followed by an additional BNT162b2 booster six months later. Individuals in the second cohort received an inactivated-virus-based BBIBP-CorV booster six months after the initial two-dose BNT162b2 vaccination. Overall, 64.3% of participants were infected with SARS-CoV-2 confirmed by PCR or antigen test; however, additional subjects from the first cohort (23%) who did not know about their previous infection but had an anti-nucleocapsid T cell response were also considered virus-experienced. According to our results, no statistically significant difference was found between the two cohorts regarding the SARS-CoV-2-specific T cell response, neutralizing anti-RBD IgG, and anti-S IgA serum antibody levels either six or twelve months after receiving the booster, despite the overall higher median values of the first cohort. The only significant difference was the higher anti-S1/S2 IgG antibody level in the first cohort one year after the BNT162b2 booster (p = 0.039). In summary, the BNT162b2 and BBIBP-CorV boosters maintain durable humoral and T cell-mediated immune memory even one year after application. Although the booster provided limited protection against Omicron breakthrough infections, as 73.6% of these infections occurred after the booster vaccination, which means 53.5% cumulative incidence, it still offered excellent protection against severe disease and hospitalization in both cohorts.

Fatigue, sleepiness and sleep quality are SARS-CoV-2 variant independent in patients with long COVID symptoms

Acute infections with SARS-CoV-2 variants of concerns (VOCs) differ in clinical presentation. Discrepancies in their long-term sequelae, commonly referred to as long COVID, however, remain to be explored. We retrospectively analyzed data of 287 patients presented at the post-COVID care of the Pulmonology Department, Semmelweis University, Budapest, Hungary, and infected with SARS-CoV-2 during a period of 3 major epidemic waves in Hungary (February-July 2021, VOC: B.1.1.7, Alpha, N = 135; August-December 2021, VOC: B.1.617.2, Delta, N = 89; and January-June 2022, VOC: B.1.1.529, Omicron; N = 63), > 4 weeks after acute COVID-19. Overall, the ratio of long COVID symptomatic (LC) and asymptomatic (NS) patients was 2:1. Self-reported questionnaires on fatigue (Fatigue Severity Scale, FSS), sleepiness (Epworth Sleepiness Scale, ESS) and sleep quality (Pittsburgh Sleep Quality Index, PSQI) showed higher scores for LC (4.79 ± 0.12, 7.45 ± 0.33 and 7.46 ± 0.27, respectively) than NS patients (2.85 ± 0.16, 5.23 ± 0.32 and 4.26 ± 0.29, respectively; p < 0.05 for all vs. LC). By comparing data of the three waves, mean FSS and PSQI scores of LC patients, but not ESS scores, exceeded the normal range in all, with no significant inter-wave differences. Considering FSS ≥ 4 and PSQI > 5 cutoff values, LC patients commonly exhibited problematic fatigue (≥ 70%) and poor sleep quality (> 60%) in all three waves. Comparative analysis of PSQI component scores of LC patients identified no significant differences between the three waves. Our findings highlight the importance of concerted efforts to manage both fatigue and sleep disturbances in long COVID patient care. This multifaceted approach should be followed in all cases infected with either VOCs of SARS-CoV-2.

Waning of SARS-CoV-2 Vaccine Effectiveness in COPD Patients: Lessons from the Delta Variant

Although the COVID-19 pandemic is profoundly changing, data on the effect of vaccination and duration of protection against infection and severe disease can still be advantageous, especially for patients with COPD, who are more vulnerable to respiratory infections. The Hungarian COVID-19 registry was retrospectively investigated for risk of infection and hospitalization by time since the last vaccination, and vaccine effectiveness (VE) was calculated in adults with COPD diagnosis and an exact-matched control group during the Delta variant of concern (VOC) wave in Hungary (September-December 2021). For the matching, sex, age, major co-morbidities, vaccination status, and prior infection data were obtained on 23 August 2021. The study population included 373,962 cases divided into COPD patients (age: 66.67 ± 12.66) and a 1:1 matched group (age: 66.73 ± 12.67). In both groups, the female/male ratio was 52.2:47.7, respectively. Among the unvaccinated, there was no difference between groups in risk for infection or hospitalization. Regarding vaccinated cases, in the COPD group, a slightly faster decline in effectiveness was noted for hospitalization prevention, although in both groups, the vaccine lost its significant effect between 215 and 240 days after the last dose of vaccination. Based on a time-stratified multivariate Cox analysis of the vaccinated cases, the hazard was constantly higher in the COPD group, with an HR of 1.09 (95%: 1.05-1.14) for infection and 1.87 (95% CI: 1.59-2.19) for hospitalization. In our study, COPD patients displayed lower vaccine effectiveness against SARS-CoV-2 infection and hospitalization but a similar waning trajectory, as vaccines lost their preventive effect after 215 days. These data emphasize revaccination measures in the COPD patient population.

Effectiveness and waning of protection with the BNT162b2 vaccine against the SARS-CoV-2 Delta variant in immunocompromised individuals

Introduction

In Hungary, the HUN-VE 3 study determined the comparative effectiveness of various primary and booster vaccination strategies during the Delta COVID-19 wave. That study included more than 8 million 18-100-year-old individuals from the beginning of the pandemic. Immunocompromised (IC) individuals have increased risk for COVID-19 and disease course might be more severe in them. In this study, we wished to estimate the risk of SARS-CoV-2 infection and COVID-19 related death in IC individuals compared to healthy ones and the effectiveness of the BNT162b2 vaccine by reassessing HUN-VE 3 data.

Patients and methods

Among the 8,087,988 individuals undergoing follow-up from the onset of the pandemic in the HUN-VE 3 cohort, we selected all the 263,116 patients with a diagnosis corresponding with IC and 6,128,518 controls from the second wave, before vaccinations started. The IC state was defined as two occurrences of corresponding ICD-10 codes in outpatient or inpatient claims data since 1 January, 2013. The control group included patients without chronic diseases. The data about vaccination, SARS-CoV-2 infection and COVID-19 related death were obtained from the National Public Health Center (NPHC) during the Delta wave. Cases of SARS-CoV-2 infection were reported on a daily basis using a centralized system via the National Public Health Center (NPHC).

Results

Out of the 263,116 IC patients 12,055 patients (4.58%) and out of the 6,128,518 healthy controls 202,163 (3.30%) acquired SARS-CoV-2 infection. Altogether 436 IC patients and 2141 healthy controls died in relation to COVID-19. The crude incidence rate ratio (IRR) of SARS-CoV-2 infection was 1.40 (95%CI: 1.37-1.42) comparing IC patients to healthy controls. The crude mortality rate ratio was 4.75 (95%CI: 4.28-5.27). With respect to SARS-CoV-2 infection, interestingly, the BNT162b2 vaccine was more effective in IC patients compared to controls. Primary vaccine effectiveness (VE) was higher in IC patients compared to controls and the booster restored VE after waning. VE regarding COVID-19 related death was less in IC patients compared to healthy individuals. Booster vaccination increased VE against COVID-19-related death in both IC patients and healthy controls.

Conclusion

There is increased risk of SARS-CoV-2 infection and COVID-19 related mortality in IC patient. Moreover, booster vaccination using BNT162b2 might restore impaired VE in these individuals.

Vaccine effectiveness against COVID-19 hospitalisation in adults (≥ 20 years) during Alpha- and Delta-dominant circulation: I-MOVE-COVID-19 and VEBIS SARI VE networks, Europe, 2021

IntroductionTwo large multicentre European hospital networks have estimated vaccine effectiveness (VE) against COVID-19 since 2021.AimWe aimed to measure VE against PCR-confirmed SARS-CoV-2 in hospitalised severe acute respiratory illness (SARI) patients ≥ 20 years, combining data from these networks during Alpha (March-June)- and Delta (June-December)-dominant periods, 2021.MethodsForty-six participating hospitals across 14 countries follow a similar generic protocol using the test-negative case-control design. We defined complete primary series vaccination (PSV) as two doses of a two-dose or one of a single-dose vaccine ≥ 14 days before onset.ResultsWe included 1,087 cases (538 controls) and 1,669 cases (1,442 controls) in the Alpha- and Delta-dominant periods, respectively. During the Alpha period, VE against hospitalisation with SARS-CoV2 for complete Comirnaty PSV was 85% (95% CI: 69-92) overall and 75% (95% CI: 42-90) in those aged ≥ 80 years. During the Delta period, among SARI patients ≥ 20 years with symptom onset ≥ 150 days from last PSV dose, VE for complete Comirnaty PSV was 54% (95% CI: 18-74). Among those receiving Comirnaty PSV and mRNA booster (any product) ≥ 150 days after last PSV dose, VE was 91% (95% CI: 57-98). In time-since-vaccination analysis, complete all-product PSV VE was > 90% in those with their last dose < 90 days before onset; ≥ 70% in those 90-179 days before onset.ConclusionsOur results from this EU multi-country hospital setting showed that VE for complete PSV alone was higher in the Alpha- than the Delta-dominant period, and addition of a first booster dose during the latter period increased VE to over 90%.

Effectiveness of homologous or heterologous immunization regimens against SARS-CoV-2 after two doses of inactivated COVID-19 vaccine: A systematic review and meta-analysis

We aimed to evaluate the effectiveness or efficacy of heterologous or homologous COVID-19 vaccine regimens against COVID-19-related outcomes after primary immunization with two doses of CoronaVac or Sinopharm COVID-19 vaccines. PubMed, EMBASE, Web of Science, and Cochrane Library databases were searched up to 31 October 2022. The primary measure was vaccine effectiveness against COVID-19 infection with homologous or heterologous booster. The results showed heterologous and homologous booster significantly improved effectiveness against COVID-19 infection compared to primary immunization. The effectiveness against COVID-19 infection was 89.19% (95%CI 78.49, 99.89) for heterologous mRNA vaccine booster, 87.00% (95%CI 82.14, 91.85) for non-replicating vector vaccine booster, 69.99% (95%CI 52.16, 87.82) for homologous booster, and 51.48% (95%CI 41.75, 61.21) for two doses of inactivated vaccine. Homologous and heterologous regimens were also effective against SARS-CoV-2 variants, and more evidence is still needed to confirm our findings.

Real-world effectiveness of mRNA COVID-19 vaccines in the elderly during the Delta and Omicron variants: Systematic review

BACKGROUND

As of 31 December 2022, there were over 6.6 million coronavirus disease 2019 (COVID-19) deaths and over 651 million cases across 200 countries worldwide. Despite the increase in vaccinations and booster shots, COVID-19 cases and deaths continue to remain high. While the effectiveness of these vaccines has already been established by different manufacturers, the fact remains that these vaccines were created quickly for global emergency use, tested under controlled clinical conditions from voluntary subjects and age groups whose general characteristics may differ from the actual general population.

AIM

To conduct a systematic review to determine the real-world effectiveness of mRNA COVID-19 vaccines in the elderly during the predominance of Delta and Omicron variants in preventing COVID-19 related infection, hospital, intensive care unit (ICU) admission and intubation, and death.

METHODS

A combination of Medical Subject Headings and non-Medical Subject Headings was carried out to identify all relevant research articles that meets the inclusion and exclusion criteria from PubMed, Cochrane, CINAHL, Scopus, ProQuest, Embase, Web of Science, and Google Scholar databases, as well as qualified research studies from pre-print servers using medRxiv and Research Square, published from January 1, 2021 - December 31, 2022.

RESULTS

As per the inclusion and exclusion criteria, the effectiveness of Pfizer-BioNTech and Moderna vaccines were evaluated from an estimated total study population of 26,535,692 using infection, hospital, ICU admission and intubation, and death as outcome measures from studies published between 2021 and 2022, conducted in New York, Finland, Canada, Costa Rica, Qatar, Greece, and Brazil. The risk of bias was evaluated using risk of bias in nonrandomized studies of interventions (ROBINS-I) tool for cohort, case-control, and cross-sectional studies. While clinical trial data on Pfizer-BioNTech and Moderna vaccines demonstrated 94% vaccine effectiveness in the elderly, the results in this study showed that vaccine effectiveness in real-world settings is marginally lower against infection (40%-89%), hospitalization (92%), ICU admission and intubation (98%-85%), and death (77%-87%) with an indication of diminished effectiveness of vaccine over time. Furthermore, 2 doses of mRNA vaccines are inadequate and only provides interim protection.

CONCLUSION

Because of the natural diminishing effectiveness of the vaccine, the need for booster dose to restore its efficacy is vital. From a research perspective, the use of highly heterogeneous outcome measures inhibits the comparison, contrast, and integration of the results which makes data pooling across different studies problematic. While pharmaceutical intervention like vaccination is important to fight an epidemic, utilizing common outcome measurements or carrying out studies with minimal heterogeneity in outcome measurements, is equally crucial to better understand and respond to an international health crisis.

Phenotypic Changes in T and NK Cells Induced by Sputnik V Vaccination

A highly effective humoral immune response induced by the Sputnik V vaccine was demonstrated in independent studies, as well as in large-scale post-vaccination follow-up studies. However, the shifts in the cell-mediated immunity induced by Sputnik V vaccination are still under investigation. This study was aimed at estimating the impact of Sputnik V on activating and inhibitory receptors, activation and proliferative senescence markers in NK and T lymphocytes. The effects of Sputnik V were evaluated by the comparison of PBMC samples prior to vaccination, and then three days and three weeks following the second (boost) dose. The prime-boost format of Sputnik V vaccination induced a contraction in the T cell fraction of senescent CD57⁺ cells and a decrease in HLA-DR-expressing T cells. The proportion of NKG2A⁺ T cells was down-regulated after vaccination, whereas the PD-1 level was not affected significantly. A temporal increase in activation levels of NK cells and NKT-like cells was recorded, dependent on whether the individuals had COVID-19 prior to vaccination. A short-term elevation of the activating NKG2D and CD16 was observed in NK cells. Overall, the findings of the study are in favor of the Sputnik V vaccine not provoking a dramatic phenotypic rearrangement in T and NK cells, although it induces their slight temporal non-specific activation.

Effectiveness of the booster dose of COVID-19 vaccine in the Basque Country during the sixth wave: A nationwide cohort study

The aim of the study was to assess the effect of a booster dose of COVID-19 vaccine on the rates of hospital ward and intensive care unit (ICU) admissions around the time of emergence of the Omicron variant in the Basque Country. A retrospective cohort population-based study was conducted. The population with any records related to COVID-19 vaccination up to 28 February 2022 was classified into four cohorts by vaccination status. For every cohort, the hospital ward and ICU admission rates were calculated for each day between November 2021 and February 2022. Generalized linear models with a negative binomial distribution were used to estimate the age-adjusted hospitalization rate ratio of the cohort of individuals who had received a booster compared to the other cohorts. The age-adjusted rates of hospital ward and ICU admissions were 70.4 % and 72.0 % lower, respectively, in the fully vaccinated plus booster group compared to the fully vaccinated but no booster group. Analysing changes in the 14-day admission incidence rates showed that as the prevalence of the Omicron variant increased, the corresponding rate ratios decreased. The immunity acquired with the booster dose allowed the hospital network to meet all the demand for hospitalization during a period of high incidence of COVID-19, despite the fact that vaccine protection decreased as the prevalence of the Omicron variant increased.

Evaluation of Waning of SARS-CoV-2 Vaccine-Induced Immunity: A Systematic Review and Meta-analysis

Importance

Estimates of the rate of waning of vaccine effectiveness (VE) against COVID-19 are key to assess population levels of protection and future needs for booster doses to face the resurgence of epidemic waves.

Objective

To quantify the progressive waning of VE associated with the Delta and Omicron variants of SARS-CoV-2 by number of received doses.

Data Sources

PubMed and Web of Science were searched from the databases' inception to October 19, 2022, as well as reference lists of eligible articles. Preprints were included.

Study Selection

Selected studies for this systematic review and meta-analysis were original articles reporting estimates of VE over time against laboratory-confirmed SARS-CoV-2 infection and symptomatic disease.

Data Extraction and Synthesis

Estimates of VE at different time points from vaccination were retrieved from original studies. A secondary data analysis was performed to project VE at any time from last dose administration, improving the comparability across different studies and between the 2 considered variants. Pooled estimates were obtained from random-effects meta-analysis.

Main Outcomes and Measures

Outcomes were VE against laboratory-confirmed Omicron or Delta infection and symptomatic disease and half-life and waning rate associated with vaccine-induced protection.

Results

A total of 799 original articles and 149 reviews published in peer-reviewed journals and 35 preprints were identified. Of these, 40 studies were included in the analysis. Pooled estimates of VE of a primary vaccination cycle against laboratory-confirmed Omicron infection and symptomatic disease were both lower than 20% at 6 months from last dose administration. Booster doses restored VE to levels comparable to those acquired soon after the administration of the primary cycle. However, 9 months after booster administration, VE against Omicron was lower than 30% against laboratory-confirmed infection and symptomatic disease. The half-life of VE against symptomatic infection was estimated to be 87 days (95% CI, 67-129 days) for Omicron compared with 316 days (95% CI, 240-470 days) for Delta. Similar waning rates of VE were found for different age segments of the population.

Conclusions and Relevance

These findings suggest that the effectiveness of COVID-19 vaccines against laboratory-confirmed Omicron or Delta infection and symptomatic disease rapidly wanes over time after the primary vaccination cycle and booster dose. These results can inform the design of appropriate targets and timing for future vaccination programs.

Real-world effectiveness and factors associated with effectiveness of inactivated SARS-CoV-2 vaccines: a systematic review and meta-regression analysis

BACKGROUND

The two inactivated SARS-CoV-2 vaccines, CoronaVac and BBIBP-CorV, have been widely used to control the COVID-19 pandemic. The influence of multiple factors on inactivated vaccine effectiveness (VE) during long-term use and against variants is not well understood.

METHODS

We selected published or preprinted articles from PubMed, Embase, Scopus, Web of Science, medRxiv, BioRxiv, and the WHO COVID-19 database by 31 August 2022. We included observational studies that assessed the VE of completed primary series or homologous booster against SARS-CoV-2 infection or severe COVID-19. We used DerSimonian and Laird random-effects models to calculate pooled estimates and conducted multiple meta-regression with an information theoretic approach based on Akaike's Information Criterion to select the model and identify the factors associated with VE.

RESULTS

Fifty-one eligible studies with 151 estimates were included. For prevention of infection, VE associated with study region, variants, and time since vaccination; VE was significantly decreased against Omicron compared to Alpha (P = 0.021), primary series VE was 52.8% (95% CI, 43.3 to 60.7%) against Delta and 16.4% (95% CI, 9.5 to 22.8%) against Omicron, and booster dose VE was 65.2% (95% CI, 48.3 to 76.6%) against Delta and 20.3% (95% CI, 10.5 to 28.0%) against Omicron; primary VE decreased significantly after 180 days (P = 0.022). For the prevention of severe COVID-19, VE associated with vaccine doses, age, study region, variants, study design, and study population type; booster VE increased significantly (P = 0.001) compared to primary; though VE decreased significantly against Gamma (P = 0.034), Delta (P = 0.001), and Omicron (P = 0.001) compared to Alpha, primary and booster VEs were all above 60% against each variant.

CONCLUSIONS

Inactivated vaccine protection against SARS-CoV-2 infection was moderate, decreased significantly after 6 months following primary vaccination, and was restored by booster vaccination. VE against severe COVID-19 was greatest after boosting and did not decrease over time, sustained for over 6 months after the primary series, and more evidence is needed to assess the duration of booster VE. VE varied by variants, most notably against Omicron. It is necessary to ensure booster vaccination of everyone eligible for SARS-CoV-2 vaccines and continue monitoring virus evolution and VE.

TRIAL REGISTRATION

PROSPERO, CRD42022353272.

Do pathogens always evolve to be less virulent? The virulence–transmission trade-off in light of the COVID-19 pandemic

The direction the evolution of virulence takes in connection with any pathogen is a long-standing question. Formerly, it was theorized that pathogens should always evolve to be less virulent. As observations were not in line with this theoretical outcome, new theories emerged, chief among them the transmission–virulence trade-off hypotheses, which predicts an intermediate level of virulence as the endpoint of evolution. At the moment, we are very much interested in the future evolution of COVID-19’s virulence. Here, we show that the disease does not fulfill all the assumptions of the hypothesis. In the case of COVID-19, a higher viral load does not mean a higher risk of death; immunity is not long-lasting; other hosts can act as reservoirs for the virus; and death as a consequence of viral infection does not shorten the infectious period. Consequently, we cannot predict the short- or long-term evolution of the virulence of COVID-19.

Effectiveness of Vaccination in Preventing COVID-19: A Community Study Comparing Four Vaccines

The course of the COVID-19 pandemic has been critically altered by the availability of vaccines. To assess the risk of COVID-19 in the vaccinated, as compared to the unvaccinated population, as well as the comparative effectiveness of the BBIBP-CorV (Sinopharm), BNT162b2 (Pfizer/BioNTech), Gam-COVID-Vac (Sputnik V) and ChAdOx1 (AstraZeneca) vaccines in the prevention of clinical infection, we carried out a retrospective study of the incidence of clinical COVID-19 in the Belgrade city municipality of Voždovac among both vaccinated and unvaccinated individuals during a 4-month period between 1 July and 31 October 2021. The study included all individuals with a symptomatic infection confirmed by a positive PCR and/or antigen test. Only those who received two vaccine doses were considered as vaccinated. The results showed that of the Voždovac population of 169,567, a total of 81,447 (48%) individuals were vaccinated by the end of the study. Vaccination coverage increased with age, ranging from 1.06% in those below age 18, to even 78.8% in those above 65 years of age. More than one half (57.5%) of all those vaccinated received BBIBP-CorV, while 25.2% received BNT162b2, 11.7% Gam-COVID-Vac and 5.6% ChAdOx1. The overall risk of infection of the vaccinated vs. the unvaccinated was 0.53 (95% CI 0.45–0.61). Compared to the incidence of COVID-19 of 8.05 per 1000 in the unvaccinated population, the relative risk in the vaccinated was 0.35 (95% CI 0.3–0.41). The overall VE was 65%, differing widely among age groups and by vaccine. VE was 79% for BNT162b2, 62% for BBIBP-CorV, 60% for ChAdOx1 and 54% for Gam-COVID-Vac. The VE for BBIBP-CorV and BNT162b2 increased with age. The obtained results demonstrate a significant overall effectiveness of anti-COVID-19 vaccination, which, however, varied significantly among the analyzed vaccines, and was the highest for BNT162b2.

Evaluation of the Efficacy of BBIBP-CorV Inactivated Vaccine Combined with BNT62b2 mRNA Booster Vaccine

OBJECTIVES

In this prospective study, SARS-CoV-2 spike protein specific total immunoglobulin (Ig) levels were analyzed before and after BNT162 b2 mRNA booster vaccination in individuals previously administered with two doses of BBIBP-CorV vaccine in comparison to immunized participants with three doses of BNT162 b2 vaccination.

METHODS

Sixty-one Caucasian volunteers (39 females, 22 males) vaccinated by BBIBP-CorV were included (mean age: 63.9 years). Sixty-one patients (41 females, 20 males) as controls were vaccinated with BNT162b2 (mean age: 59.9 years). Both groups received the third booster BNT162b2 vaccine. Total anti-SARS-CoV-2 S1-RBD Ig levels were measured by an immunoassay (Roche Diagnostics) and their calculated ratios after/before booster dose were compared between the two groups.

RESULTS

At baseline, significantly lower anti-SARS-CoV-2 S1-RBD total antibody levels were determined after initial immunization by two doses of inactivated BBIBP-CorV compared to BNT62b2 mRNA vaccine (p < 0.001). After BNT162b2 boosters, similarly high total Ig levels were detected in both the heterologous (27,195 [15,604-42,754] BAU/mL, p < 0.001) and the homologous booster cohort (24,492 [13,779-42,671] BAU/mL, p < 0.001) compared to baseline. Hence, the ratio of after/before total Ig levels was significantly higher with heterologous vs homologous immunization (p < 0.001).

CONCLUSION

To address the concept that basic BBIBP-CorV vaccination is not as effective as BNT162b, we analyzed the effect of heterologous vaccination with BNT162b2. Our results suggest that BNT162b2 can successfully boost the effects of two-dose BBIBP-CorV vaccination.

The Impact of Comorbidities and Obesity on the Severity and Outcome of COVID-19 in Hospitalized Patients-A Retrospective Study in a Hungarian Hospital

Patients with comorbidities and obesity are more likely to be hospitalized with coronavirus disease 2019 (COVID-19), to have a higher incidence of severe pneumonia and to also show higher mortality rates. Between 15 March 2020 and 31 December 2021, a retrospective, single-center, observational study was conducted among patients requiring hospitalization for COVID-19 infection. Our aim was to investigate the impact of comorbidities and lifestyle risk factors on mortality, the need for intensive care unit (ICU) admission and the severity of the disease among these patients. Our results demonstrated that comorbidities and obesity increased the risk for all investigated endpoints. Age over 65 years and male sex were identified as independent risk factors, and cardiovascular diseases, cancer, endocrine and metabolic diseases, chronic kidney disease and obesity were identified as significant risk factors. Obesity was found to be the most significant risk factor, associated with considerable odds of COVID-19 mortality and the need for ICU admission in the under-65 age group (aOR: 2.95; p < 0.001 and aOR: 3.49, p < 0.001). In our study, risk factors that increased mortality and morbidity among hospitalized patients were identified. Detailed information on such factors may support therapeutic decision making, the proper targeting of vaccination campaigns and the effective overall management of the COVID-19 epidemic, hence reducing the burden on the healthcare system.

Long-term adaptive response in COVID-19 vaccine recipients and the effect of a booster dose

We examined the immune response in subjects previously infected with SARS-CoV2 and infection-naïve 9 months after primary 2-dose COVID-19 mRNA vaccination and 3 months after the booster dose in a longitudinal cohort of healthcare workers. Nine months after primary vaccination, previously infected subjects exhibited higher residual antibody levels, with significant neutralizing activity against distinct variants compared to infection-naïve subjects. The higher humoral response was associated with higher levels of receptor binding domain (RBD)-specific IgG⁺ and IgA⁺ memory B cells. The booster dose increased neither neutralizing activity, nor the B and T cell frequencies. Conversely, infection-naïve subjects needed the booster to achieve comparable levels of neutralizing antibodies as those found in previously infected subjects after primary vaccination. The neutralizing titer correlated with anti-RBD IFNγ producing T cells, in the face of sustained B cell response. Notably, pre-pandemic samples showed high Omicron cross-reactivity. These data show the importance of the booster dose in reinforcing immunological memory and increasing circulating antibodies in infection-naïve subjects.

Efficacy of COVID-19 vaccination in organized group: results of a prospective study

   Objective: to assess the efficacy of COVID-19 vaccination against in organized group.   Materials and methods: A total of 122 adults, employees of a higher education institution participated in the study. Study participants were observed prospectively and filled out a questionnaire where they indicated their age, presence of chronic diseases, history of COVID-19 and vaccination status.   Findings: the study participants were divided into two groups: 59 vaccinated (48.36 %) and 63 unvaccinated (51.64 %) individuals with no differences in age between the groups. There were significantly fewer confirmed cases of COVID-19 in the vaccinated group (р = 0,0008457, df = 1; χ2 = 11,138), significant differences (p = 0.0084; df = 4; χ2 =13.678) were observed in the number of cases among study participants based on their vaccination status.   Conclusion: participants diagnosed with pneumonia were 75 % unvaccinated (p = 0,00729; df = 1; χ2 = 7,2). All hospitalized study participants were unvaccinated (p = 0,004678; χ2 =8,0). None of the vaccinated participants needed respiratory support (p = 0,0455; df = 1; χ2 = 4,0). Chronic disease in vaccinated subjects made a significant (p = 0,04563; df = 2; χ2 = 6,1743) impact on COVID-19 severity.

Real-Time Monitoring of the Effectiveness of Six COVID-19 Vaccines against Laboratory-Confirmed COVID-19 in Hungary in 2021 Using the Screening Method

Several studies have reported the waning effectiveness of COVID-19 vaccines. This study aims to demonstrate the applicability of the screening method for estimating vaccine effectiveness (VE) in a pandemic. We report VE in Hungary, estimated with the screening method, in 2021, covering a period of Alpha and the Delta variant, including the booster dose roll-out. Hungary is in a unique position to use six different vaccines in the same population. All vaccines provided a high level of protection initially, which declined over time. While the picture is different in each age group, the waning of immunity is apparent for all vaccines, especially in the younger age groups and the Sinopharm, Sputnik-V, and AstraZeneca vaccines, which performed similarly. This is clearly reversed by booster doses, more prominent for those three vaccines, where the decline in protection is more evident. Overall, two vaccines, Pfizer/BioNTech and Moderna, tend to produce the best results in all age groups, even with waning immunity considered. Using the screening method in future pandemic waves is worthwhile, especially in countries struggling with a lack of resources or when there is a need to deliver VE results within a short timeframe due to urgent decision-making.

Comparison of Homologous and Heterologous Booster SARS-CoV-2 Vaccination in Autoimmune Rheumatic and Musculoskeletal Patients

Vaccination against SARS-CoV-2 to prevent COVID-19 is highly recommended for immunocompromised patients with autoimmune rheumatic and musculoskeletal diseases (aiRMDs). Little is known about the effect of booster vaccination or infection followed by previously completed two-dose vaccination in aiRMDs. We determined neutralizing anti-SARS-CoV-2 antibody levels and applied flow cytometric immunophenotyping to quantify the SARS-CoV-2 reactive B- and T-cell mediated immunity in aiRMDs receiving homologous or heterologous boosters or acquired infection following vaccination. Patients receiving a heterologous booster had a higher proportion of IgM+ SARS-CoV-2 S+ CD19+CD27+ peripheral memory B-cells in comparison to those who acquired infection. Biologic therapy decreased the number of S+CD19+; S+CD19+CD27+IgG+; and S+CD19+CD27+IgM+ B-cells. The response rate to a booster event in cellular immunity was the highest in the S-, M-, and N-reactive CD4+CD40L+ T-cell subset. Patients with a disease duration of more than 10 years had higher proportions of CD8+TNF-α+ and CD8+IFN-γ+ T-cells in comparison to patients who were diagnosed less than 10 years ago. We detected neutralizing antibodies, S+ reactive peripheral memory B-cells, and five S-, M-, and N-reactive T-cells subsets in our patient cohort showing the importance of booster events. Biologic therapy and <10 years disease duration may confound anti-SARS-CoV-2 specific immunity in aiRMDs.