Safety and immunogenicity of an inactivated COVID-19 vaccine, BBIBP-CorV, in people younger than 18 years: a randomised, double-blind, controlled, phase 1/2 trial

Long-Term Safety Analysis of the BBV152 Coronavirus Vaccine in Adolescents and Adults: Findings from a 1-Year Prospective Study in North India

BACKGROUND AND OBJECTIVE

Evidence on the long-term safety of COVID-19 vaccines is scarce. Here, in continuation of our previously published results on short-term safety, we provide data on the long-term safety of the BBV152 vaccine in adolescents and adults.

METHODS

This was a prospective observational study conducted from January 2022 to August 2023. Adolescents and adults receiving the BBV152 vaccine were interviewed telephonically about long-term adverse events of special interest (AESIs) after 1 year of vaccination. Risk factors of AESIs and AESIs persistent for at least 1 month were identified.

RESULTS

Out of 1024 individuals enrolled, 635 adolescents and 291 adults could be contacted during the 1-year follow-up. Viral upper respiratory tract infections were reported by 304 (47.9%) adolescents and 124 (42.6%) adults in this period. New-onset skin and subcutaneous disorders (10.5%), general disorders (10.2%), and nervous system disorders (4.7%) were the common AESIs in adolescents. General disorders (8.9%), musculoskeletal disorders (5.8%), and nervous system disorders (5.5%) were the common AESIs in adults. Menstrual abnormalities were noticed in 4.6% of female participants. Ocular abnormalities and hypothyroidism were observed in 2.7% and 0.6% of participants, respectively. Among serious AESIs (1%), stroke and Guillain-Barre syndrome were identified in 0.3% and 0.1% of participants, respectively. Among adolescents, female individuals, those with a history of allergy and post-vaccination typhoid were respectively at 1.6, 2.8, and 2.8 times higher risk of AESIs. The majority of the AESIs persisted at the 1-year follow-up. Female individuals, adolescents with pre-vaccination COVID-19, those with co-morbidities, and those with post-vaccination typhoid had respectively 1.6, 2, 2.7, and 3.2 times higher odds of persistent AESIs. Adults with co-morbidities had more than 2 times higher odds of AESIs and persistent AESIs.

CONCLUSIONS

The patterns of AESIs developing after BBV152 differed from those reported with other COVID-19 vaccines as well as between adolescents and adults. With the majority of AESIs persisting for a significant period, extended surveillance of COVID-19-vaccinated individuals is warranted to understand the course and outcomes of late-onset AESIs. Serious AESIs might not be uncommon and necessitate enhanced awareness and larger studies to understand the incidence of immune-mediated phenomena post-COVID-19 vaccination. The relationship of AESIs with sex, co-morbidities, pre-vaccination COVID-19, and non-COVID illnesses should be explored in future studies.

Efficacy, Effectiveness, and Safety of COVID-19 Vaccine Compared to Placebo in Preventing COVID-19 Infection among 12-17 Years Old: A Systematic Review

Objectives

The World Health Organization recently revised their recommendations and considered healthy children and adolescents as low priority group for COVID-19 vaccine. This review comprehensively assessed existing clinical evidence on COVID-19 vaccine in 12-17 years old.

Methods

Included in this review were any type of study that investigated the efficacy, immunogenicity, safety, and effectiveness of COVID-19 vaccine on protection against SARS-COV-2 infection in 12-17 years old. Various electronic databases were searched up to March 15, 2023. Studies were screened, data extracted, risk of bias appraised, and certainty of evidence was judged using GRADE. Review Manager 5.4 was used to estimate pooled effects. Difference between the two groups was described as mean difference for continuous variables and as relative risk or odds ratio for categorical variables.

Results

There were six randomized controlled trials and 16 effectiveness studies (8 cohorts and 8 case control). Low certainty evidence showed that BNT162b2 (Pfizer) was effective, immunogenic, and safe in healthy adolescents. There were 15 effectiveness studies on BNT162b2 (Pfizer) in healthy adolescent and one on immunocompromised patients. It was protective against infection with any of the variants, with higher protection against Delta than Omicron. BNT162b2 is protective against hospitalization and emergency and urgent care (high certainty); and critical care and MIS-C (low). Very low certainty evidence noted that BNT 162b2 was also immunogenic in 12-21 years old with rheumatic diseases while on immunomodulatory treatment but with possible increased exacerbation of illness. Low certainty evidence demonstrated that mRNA-1273 (Moderna) was effective, immunogenic, and safe. Low to very low certainty evidence were noted on the safety and immunogenicity of two vector base vaccines (ChAdOx1-19 and Ad5 vector COVID vaccine) and two inactivated vaccines (CoronaVac and BBIBP CorV).

CONCLUSION

There is presently low certainty evidence on the use of RNA vaccines in 12-17 years old. The recommendation on its use is weak. There is presently insufficient evidence for the use of inactivated and vector-based COVID-19 vaccines. Different countries should consider whether to vaccinate healthy adolescent without comprising the other recommended immunization and health priorities that are crucial for this age group. Other factors including cost-effectiveness of vaccination and disease burden should be accounted.

Immunogenicity and safety of a recombinant COVID-19 vaccine (ZF2001) as heterologous booster after priming with inactivated vaccine in healthy children and adolescents aged 3-17 years: an open-labeled, single-arm clinical trial

Considering that neutralizing antibody levels induced by two doses of the inactivated vaccine decreased over time and had fallen to low levels by 6 months, and homologous and heterologous booster immunization programs have been implemented in adults in China. The booster immunization of recombinant COVID-19 vaccine (ZF2001) after priming with inactivated vaccine in healthy children and adolescents has not been reported. We performed an open-labeled, single-arm clinical trial to evaluate the safety and immunogenicity of heterologous booster immunization with ZF2001 after priming with inactivated vaccine among 240 population aged 3-17 years in China. The primary outcome was immunogenicity, including geometric mean titers (GMTs), geometric mean ratios (GMRs) and seroconversion rates of SARS-CoV-2 neutralizing antibodies against prototype SARS-CoV-2 and Omicron BA.2 variant at 14 days after vaccination booster. On day 14 post-booster, a third dose booster of the ZF2001 provided a substantial increase in antibody responses in minors, and the overall occurrence rate of adverse reactions after heterologous vaccination was low and all adverse reactions were mild or moderate. The results showed that the ZF2001 heterologous booster had high immunogenicity and good safety profile in children and adolescents, and can elicit a certain level of neutralizing antibodies against Omicron.Trial registration NCT05895110 (Retrospectively registered, First posted in ClinicalTrials.gov date: 08/06/2023).

Immune features revealed by single-cell RNA and single-cell TCR/BCR sequencing in patients with rheumatoid arthritis receiving COVID-19 booster vaccination

Coronavirus disease 2019 (COVID-19), caused by SARS-CoV-2, have profoundly affected human health. Booster COVID-19 vaccines have demonstrated significant efficacy in reducing infection and severe cases. However, the effects of booster COVID-19 vaccines on key immune cell subsets and their responses in rheumatoid arthritis (RA) are not well understood. By using single-cell RNA sequencing (scRNA-seq) combined with scTCR/BCR-seq analysis, a total of 8 major and 27 minor cell clusters were identified from paired peripheral blood mononuclear cells (PBMCs) which were collected 1 week before and 4 weeks after booster vaccination in stable RA patients. Booster vaccination only had limited impact on the composition and proportions of PBMCs cell clusters. CD8+ cytotoxic T cells (CD8+T_CTL) showed a trend toward an increase after vaccination, while naive B cells and conventional dendritic cells (cDCs) showed a trend toward a decrease. Transcriptomic changes were observed after booster vaccination, primarily involving T/B cell receptor signaling pathways, phagosome, antigen processing and presenting, and viral myocarditis pathways. Interferon (IFN) and pro-inflammatory response gene sets were slightly upregulated across most major cell subpopulations in COVID-19 booster-vaccinated RA individuals. Plasma neutralizing antibody titers significantly increased after booster COVID-19 vaccination (p = 0.037). Single-cell TCR/BCR analysis revealed increased B cell clone expansion and repertoire diversity postvaccination, with no consistent alterations in T cells. Several clonotypes of BCRs and TCRs were identified to be significantly over-represented after vaccination, such as IGHV3-15 and TRBV28. Our study provided a comprehensive single-cell atlas of the peripheral immune response and TCR/BCR immune repertoire profiles to inactivated SARS-CoV-2 booster vaccination in RA patients, which helps us to understand vaccine-induced immune responses better.

Comparative efficacy and safety of COVID-19 vaccines in phase III trials: a network meta-analysis

BACKGROUND

Over a dozen vaccines are in or have completed phase III trials at an unprecedented speed since the World Health Organization (WHO) declared COVID-19 a pandemic. In this review, we aimed to compare and rank these vaccines indirectly in terms of efficacy and safety using a network meta-analysis.

METHODS

We searched Embase, MEDLINE, and the Cochrane Library for phase III randomized controlled trials (RCTs) from their inception to September 30, 2023. Two investigators independently selected articles, extracted data, and assessed the risk of bias. Outcomes included efficacy in preventing symptomatic severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and the incidence of serious adverse events (SAEs) according to vaccine type and individual vaccines in adults and elderly individuals. The risk ratio and mean differences were calculated with 95% confidence intervals using a Bayesian network meta-analysis.

RESULTS

A total of 25 RCTs involving 22 vaccines were included in the study. None of vaccines had a higher incidence of SAEs than the placebo. Inactivated virus vaccines might be the safest, with a surface under the cumulative ranking curve (SUCRA) value of 0.16. BIV1-CovIran showed the highest safety index (SUCRA value: 0.13), followed by BBV152, Soberana, Gam-COVID-Vac, and ZF2001. There were no significant differences among the various types of vaccines regarding the efficacy in preventing symptomatic SARS-CoV-2 infection, although there was a trend toward higher efficacy of the mRNA vaccines (SUCRA value: 0.09). BNT162b2 showed the highest efficacy (SUCRA value: 0.02) among the individual vaccines, followed by mRNA-1273, Abdala, Gam-COVID-Vac, and NVX-CoV2373. BNT162b2 had the highest efficacy (SUCRA value: 0.08) in the elderly population, whereas CVnCoV, CoVLP + AS03, and CoronaVac were not significantly different from the placebo.

CONCLUSIONS

None of the different types of vaccines were significantly superior in terms of efficacy, while mRNA vaccines were significantly inferior in safety to other types. BNT162b2 had the highest efficacy in preventing symptomatic SARS-CoV-2 infection in adults and the elderly, whereas BIV1-CovIran had the lowest incidence of SAEs in adults.

The effect of perceived social support and health literacy on parental COVID-19 vaccine hesitation in preschool children: a cross-sectional study

Children are generally susceptible to COVID-19, and infection with COVID-19 may cause serious harm to children. COVID-19 vaccination is an effective way to prevent infection at present, and many factors affect children's COVID-19 vaccination. This study aimed to explore the effects of perceived social support and health literacy on hesitancy towards first and second vaccine dose. This cross-sectional study was conducted in the Minhang District of Shanghai, China, in October 2022. A total of 1150 parents of preschool children from 10 kindergartens participated. The survey encompassed four sections, capturing data on sociodemographic attributes, health literacy, perceived social support, and parental COVID-19 vaccine hesitancy. Health literacy was measured using a self-designed questionnaire consisting of four dimensions. Perceived social support was assessed using the MSPSS questionnaire. Hierarchical multiple logistic regression was used to examine the relationship between the independent variables and parental hesitancy towards the first and second doses of COVID-19 vaccine. Parental hesitancy rate for the first dose of the COVID-19 vaccine was 69.6%, and for the second dose, it was 33.1%. The final integrated model showed that parental hesitancy towards the first and the second dose of COVID-19 vaccine was associated with parental educational level, allergy in children, information decision-making and information comprehension ability, perceived social support from family and friends. Health literacy and perceived social support are influence factors for parental hesitancy towards COVID-19 vaccine for preschool children. The findings will provide insights for future intervention studies on COVID-19 vaccine hesitancy and inform the development of vaccination policies.

Fever clinic construction and management targeted to prevention and control of healthcare-associated respiratory viral infections in Jiangsu, China: A cross-sectional observational study

To analyze the post-COVID-19 construction and management of fever clinics targeted to prevention and control of healthcare-associated respiratory viral infections in medical institutions at all levels in China, and to provide a basis for promoting their standardized construction, we conducted this survey on the construction of fever clinics in 429 medical institutions of Jiangsu Province from July to December 2020. Contents of the questionnaire included the general situation of medical institutions, the construction status and future construction plans of fever clinics. We find the construction rate of fever clinic in medical institutions of Jiangsu province was 75.3%. All construction indicators, quality management systems and processes fail to fully meet the requirements of documents and standards. Jiangsu province actively promotes the construction of fever clinic layout, but there is still a gap with the construction standard. As a result, it is necessary to further promote standardized construction of fever clinic, and necessary financial input should be increased to expand all constructions of fever clinic in primary medical institutions.

Effect of inactivated vaccine boosters against severe and critical COVID-19 during the Omicron BA.5 wave: A retrospective analysis of hospitalized patients in China

Few real-world analyses of the ability of vaccines to protect against severe COVID-19 have been published. In this real-world study, we compared the prevalence of severe or critical COVID-19 between patients at our hospital who were not vaccinated against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) or who had been vaccinated partial, full, or booster course with the CoronaVac, containing inactivated virus propagated in Vero cells. Data from electronic health records were retrospectively analyzed for 4090 inpatients with COVID-19 who were treated at West China Hospital, Chengdu between December 6, 2022 and February 14, 2023. Clinicodemographic characteristics and COVID-19 severity were compared among patients who had been vaccinated 0, 1, 2 or more times with inactivated vaccine CoronaVac. To evaluate vaccine effectiveness over time, we plotted Kaplan-Meier curves with the percentage of patients with the outcome of severe or critical COVID-19 from the time of their last vaccine dose according to vaccination status. Ordinal logistic regression was used to assess associations between vaccination status and COVID-19 severity. Cox regression was used to identify risk factors for severe or critical COVID-19. Among the 4090 patients, 171 had been vaccinated partial and 423 twice with the full CoronaVac regimens, while 905 had been vaccinated three times (boosted). The prevalence of severe or critical COVID-19 among patients was 11 percentage points lower among those vaccinated (40%) at least twice than among those unvaccinated (51%) (p＜0.001), while it was 10% points lower among those who had received a booster (41%) than among those unvaccinated (51%) (p＜0.001). Protection against severe or critical COVID-19 due to vaccination was significantly weakened by being older than 65 years, being male, or having diabetes, chronic heart disease, autoimmune disease, or chronic lung disease. Completing a full course of immunization with inactivated vaccine CoronaVac against SARS-CoV-2 can reduce the risk of severe or critical COVID-19 due to the Omicron BA.5 subvariant.

An Outline of the Immunogenic Potential of Progressing SARSCoV- 2 Vaccine Technologies among Children and Adolescents

BACKGROUND

SARS-CoV-2, a highly dynamic beta-coronavirus, can afflict all age groups. Notably, over 16100 mortalities have been recorded among children as yet. In this regard, many vaccine projects are operational to assess immuno-potency among young cohorts. A bulk of reports have evidenced the efficacy of these immunization technologies in the elderly population, though the impact is yet to be determined among children.

OBJECTIVES

This review is envisioned to outline the current efficacy of contributing vaccine technologies and examine the dose-dependent impact of immunization regimens in lowering the risks of SARS-CoV-2 infections among children and adolescents. Furthermore, the current review exclusively estimated the vaccine impact at current doses.

METHODS

A total of 52 research papers extracted from PubMed, Pubmed Central, Science Direct, Research Gate, Google Scholar and Semantic Scholar were screened along with an emphasis on patents. Inclusion criteria involved all published reports directly or indirectly linked to the contributing vaccine candidates that are operational among the young cohort. Unrelated research papers were excluded from the study. Key search terminologies included information on vaccine identifiers, such as name, type and clinical trial ID, and successively restricted to children and adolscents age groups.

RESULTS

Several vaccine designs, such as mRNA-based vaccinations, viral vector vaccines, DNA vaccines, inactivated vaccines, recombinant vaccines, and protein-based immunizations, are being examined at various stages of clinical trials to gauge the effects on children and adolescents. With reference to the published reports, the mRNA 1273 (1610 GMT; 6-10 yrs, 1401 GMT; 12-15 yrs), BNT162b2 (1407 GMT; 6 months- <2 yrs, 1535 GMT; 2-4 yrs, 4583 GMT; 5-11 yrs, 1239.5 GMT; 12-15 yrs) and Ad5 nCoV (1037.5 GMT; 6-17 yrs) offered relatively high neutralization titers with sharp seroconversion rates compared to MVC-COV1901 (648.5 GMT; 12-17 yrs) and ZyCoV-D (133.49 GMT; 12-17 yrs), which produced modest immune responses.

CONCLUSION

Currently, the WHO is analyzing emerging evidence to issue an emergency use list of vaccines for vaccinating children and adolescents.

Side effects following first dose of COVID-19 vaccination in Ho Chi Minh City, Vietnam

Vaccines are strongly recommended globally as an effective measure to prevent serious illness from and spread of COVID-19. Concerns about safety following vaccination continue to be the most common reason that people do not accept the vaccine. This retrospective study was carried out on 4341 people who received the first dose of ChAdOx1 nCoV-19, BBIBP-CorV, or mRNA-1273 vaccine at Jio Health Clinic in Ho Chi Minh City, Vietnam. Post-injection side effects were either reported by participants or actively collected by health care staff by means of telemedicine. Local side effects were reported by 35.5% of all individuals, with pain being the most common symptom (33.3%). Systemic side effects were reported by 44.2% of individuals, with fever (25.3%) and fatigue (21.4%) being the most common. Age ≤60 years, female gender, and ChAdOx1 nCoV-19 were significant independent risk factors for both local and systemic side effects, while a history of allergy was significant as a risk factor for local side effects. A total of 43 individuals (1.0%) reported concerning symptoms of rare severe complications, which were addressed and treated by physicians via Jio Health app.

Evolution of SARS-CoV-2 Spikes shapes their binding affinities to animal ACE2 orthologs

IMPORTANCE

Spike-receptor interaction is a critical determinant for the host range of coronaviruses. In this study, we investigated the SARS-CoV-2 WHU01 strain and five WHO-designated SARS-CoV-2 variants of concern (VOCs), including Alpha, Beta, Gamma, Delta, and the early Omicron variant, for their Spike interactions with ACE2 proteins of 18 animal species. First, the receptor-binding domains (RBDs) of Alpha, Beta, Gamma, and Omicron were found to display progressive gain of affinity to mouse ACE2. More interestingly, these RBDs were also found with progressive loss of affinities to multiple ACE2 orthologs. The Omicron RBD showed decreased or complete loss of affinity to eight tested animal ACE2 orthologs, including that of some livestock animals (horse, donkey, and pig), pet animals (dog and cat), and wild animals (pangolin, American pika, and Rhinolophus sinicus bat). These findings shed light on potential host range shift of SARS-CoV-2 VOCs, especially that of the Omicron variant.

Mucosal response of inactivated and recombinant COVID-19 vaccines in Congolese individuals

BACKGROUND

The efficacy of immunization against an airborne pathogen depends in part on its ability to induce antibodies at the major entry site of the virus, the mucosa. Recent studies have revealed that mucosal immunity is poorly activated after vaccination with messenger RNA vaccines, thus failing in blocking virus acquisition upon its site of initial exposure. Little information is available about the induction of mucosal immunity by inactivated and recombinant coronavirus disease 2019 (COVID-19) vaccines. This study aims to investigate this topic.

METHODS

Saliva and plasma samples from 440 healthy Congolese were collected including (1) fully vaccinated 2 month postvaccination with either an inactivated or a recombinant COVID-19 vaccine and (2) nonvaccinated control group. Total anti-severe acute respiratory syndrome coronavirus 2 receptor-binding domain IgG and IgA antibodies were assessed using in-house enzyme-linked immunosorbent assays for both specimens.

FINDINGS

Altogether, the positivity of IgG was significantly higher in plasma than in saliva samples both in vaccinated and nonvaccinated control groups. Inversely, IgA positivity was slightly higher in saliva than in plasma of vaccinated group. The overall IgG and IgA levels were respectively over 103 and 14 times lower in saliva than in plasma samples. We found a strong positive correlation between IgG in saliva and plasma also between IgA in both specimens (r = .70 for IgG and r = .52 for IgA). Interestingly, contrary to IgG, the level of salivary IgA was not different between seropositive control group and seropositive vaccinated group. No significant difference was observed between recombinant and inactivated COVID-19 vaccines in total IgG and IgA antibody concentration release 2 months postvaccination both in plasma and saliva.

CONCLUSION

Inactivated and recombinant COVID-19 vaccines in use in the Republic of Congo poorly activated mucosal IgA-mediated antibody response 2 months postvaccination.

Immunogenicity and Safety of a SARS-CoV-2 Inactivated Vaccine KCONVAC in Chinese Children: Randomized, Double-blind, Placebo-controlled Phase 1 and 2 Trials

BACKGROUND

It is important to extend the indication of severe acute respiratory syndrome coronavirus 2 vaccine to children to improve the vaccine intake rate and reduce infection in this population.

METHODS

In 2 phase 1 and phase 2 randomized, double-blind and placebo-controlled trials, 84 and 480 Chinese healthy children 3 to 17 years old were enrolled, respectively, and randomized in 3:1 ratio to receive 2 doses of a severe acute respiratory syndrome coronavirus 2 inactivated vaccine, KCONVAC or placebo. The 2 doses were given 28 days apart. Adverse events (AEs) were recorded through Day 28 after each dosing. Live virus neutralizing antibody and receptor binding domain antibody (RBD-IgG) were tested before vaccination and after the second dose.

RESULTS

Two doses of the vaccine, KCONVAC, elicited geometric mean titers of 142-150 for neutralizing antibody and 4154-4253 for RBD-IgG 28 days after the second dose. Seroconversion rates were 100% after 2 doses for both antibodies in both trials. The predominant AEs were injection-site pain, cough and fever. Most AEs were grade 1 or 2 in intensity. Five participants reported 6 vaccination-unrelated serious AEs in the phase 2 trial.

CONCLUSIONS

Two doses of this study vaccine, KCONVAC, were well tolerated and immunogenic in children 3 to 17 years of age.

Incidence of SARS-CoV-2 infection in children shortly after ending zero-COVID-19 policy in China on December 7, 2022: a cross-sectional, multicenter, seroepidemiological study

Background

China discontinued the zero-COVID-19 policy on December 7, 2022, and then COVID-19 surged mid-December 2022 through mid-January 2023. However, the actual incidence was unknown. This study aimed to estimate the incidence of SARS-CoV-2 infection in children shortly after ending the zero-COVID-19 policy.

Methods

This multicenter cross-sectional study included 1,065 children aged 8 months to 12 years from seven hospitals at six regions across Jiangsu province, based on the convenience sampling, from February 10 to March 10, 2023. Group I comprised 324 children aged 8 months-2 years without COVID-19 vaccination, group II consisted of 338 preschool children aged 3-5 years with varied vaccination history, and group III contained 403 primary school children aged 6-12 years with mostly vaccinated. The COVID-19 vaccines were composed of inactivated SARS-CoV-2. In addition, 96 children's sera collected in 2014 were included as negative controls. IgG and IgM antibodies against nucleocapsid (N) and subunit 1 of spike (S1) of SARS-CoV-2 (anti-N/S1) were measured with commercial kits (YHLO Biotech, Shenzhen, China).

Results

None of the 96 children (5.1 ± 3.5 years; 58.3% boys) in 2014 was positive for anti-N/S1 IgG or IgM. Of the 1,065 children (5.0 ± 3.5 years; 56.0% boys), 988 (92.8%) were anti-N/S1 IgG positive but none was anti-N/S1 IgM positive. The positive rate of anti-N/S1 IgG in Group I, II, and III was 90.4, 88.5, and 98.3%, respectively, with significantly higher in group III than in groups I and II (p < 0.0001). The median antibody titers in group III (381.61 AU/ml) were much higher than that in group I (38.34 AU/ml) and II (51.88 AU/ml; p < 0.0001).

Conclusion

More than 90% children experienced SARS-CoV-2 infection shortly after ending zero-COVID-19 policy in China, much higher than estimated infections by other studies. The widespread SARS-CoV-2 infection in unvaccinated children should be influential on the policy of COVID-19 vaccination in children in the future.

Clinical characteristics, outcomes, and risk factors of SARS-CoV-2 breakthrough infections among 572 fully vaccinated (BBIBP-CorV) hospitalized patients

Background

Breakthrough infections have been widely reported in vaccinated individuals. However, the clinical characteristics, outcomes, and risk factors of SARS-CoV-2 breakthrough infections among fully vaccinated (BBIBP-CorV) hospitalized patients have not yet been fully elucidated.

Methods

In the single-center cohort study conducted at Xiangya Hospital of Central South University, we enrolled the hospitalized COVID-19 patients who had received full (2 doses) vaccination with the BBIBP-CorV vaccine between December 5, 2022, and January 31, 2023. We collected and analyzed information related to clinical characteristics, laboratory results, treatments, outcomes and prognostic data. Univariate and multivariable Cox regression were performed to assess the impact of clinical characteristics and laboratory results on the composite outcome (including the initiation of endotracheal intubation, non-invasive respiratory support, intensive care unit admission, and all-cause death).

Results

A total of 572 COVID-19 hospitalized patients with fully vaccinated (BBIBP-CorV) were included. The median age of the patients was 66 years (IQR 53, 74). The most common symptoms included fever (347 [60.7 %]), dry cough (401 [70.1 %]), and expectoration (333 [58.2 %]). Among those with pre-existing chronic comorbidities, 44.2 % had hypertension and 20.5 % had diabetes. Laboratory tests revealed that the majority of patients (425/549 [77.4 %]) had normal white blood cell counts. Composite outcome occurred in 11.9 % of patients, with 96.7 % of patients discharged and 3.3 % of patients died. Multivariate Cox regression analyses suggested that the NLR >4 (adjusted HR, 5.50 [95%CI: 1.56-19.47]; P = 0.008), D-dimer >0.5 mg/ml (adjusted HR, 2.17 [95%CI: 1.03-4.59]; P = 0.042) and procalcitonin >0.1 ng/ml (adjusted HR, 3.22 [95%CI: 1.38-7.52]; P = 0.007) were independently associated with the composite outcome.

Conclusion

Breakthrough infection after being fully vaccinated (BBIBP-CorV) is more likely to occur in older patients and patients with pre-existing chronic comorbidities. NLR >4, D-dimer >0.5 mg/ml and procalcitonin >0.1 ng/ml were independent risk factors for composite outcome.

Immunogenicity and Tolerability of a SARS-CoV-2 TNX-1800, a Live Recombinant Poxvirus Vaccine Candidate, in Syrian Hamsters and New Zealand White Rabbits

TNX-1800 is a preclinical stage synthetic-derived live attenuated chimeric horsepox virus vaccine engineered to express the SARS-CoV-2 spike (S) gene. The objectives of this study were to assess the safety, tolerability, and immunogenicity of TNX-1800 administration in Syrian golden hamsters and New Zealand white rabbits. Animals were vaccinated at three doses via percutaneous inoculation. The data showed that the single percutaneous administration of three TNX-1800 vaccine dose levels was well tolerated in both hamsters and rabbits. At all dose levels, rabbits were more decerning regarding vaccine site reaction than hamsters. Lastly, no TNX-1800 genomes could be detected at the site of vaccination. Post-vaccination, all animals had anti-SARS-CoV-2 spike protein IgG specific antibody responses. These data demonstrate that TNX-1800 infection was limited, asymptomatic, and cleared by the end of this study, and a single dose was able to generate immune responses.

CoronaVac and BBIBP-CorV vaccines against SARS-CoV-2 during predominant circulation of Omicron BA.5.2 and BF.7 in China, a retrospective cohort study

Pandemic of COVID-19 hit China at the end of 2022. According to China Center for Disease Control and Prevention, Omicron BA.5.2 and BF.7 were the main circulating variants. Chinese people had a high COVID-19 vaccination rate, and the most widely used vaccines were CoronaVac (Sinovac) and BBIBP-CorV (Sinopharm). An online questionnaire was distributed to survey the vaccination history and infection information of China mainland residents during this pandemic. A total of 4250 subjects were included for propensity score matching, 566 unvaccinated subjects and 1072 vaccinated subjects were finally included to analyze the effects of the two vaccines on BA.5.2 and BF.7. The SARS-CoV-2 infection rate was 84.5% in the vaccinated group and 82.3% in the unvaccinated group (p = 0.255). Vaccinated subjects had significantly higher rates of COVID-19-related symptoms, including fever, cough, nasal obstruction, runny nose, and sore throat. However, vaccinated people had lower risk of pneumonia (odds ratio [OR]: 0.467, 95% confidence interval [CI]: 0.286-0.762) and hospitalization (OR: 0.290, 95% CI: 0.097-0.870) due to COVID-19. In general, the current study did not observe the protective effect of CoronaVac and BBIBP CorV against BA.5.2 and BF.7 infection. However, these vaccines can still reduce the risk of adverse outcomes such as pneumonia and hospitalization.

Comparison of immune response to SARS-COV-2 vaccine in COVID-recovered versus non-infected Individuals

To determine the antibody levels at 6 months in SARS-CoV-2 vaccinated individuals in COVID-recovered versus non-infected groups to determine the need to administer booster COVID vaccine in each group. Prospective longitudinal study. Pathology Department, Combined Military Hospital, Lahore for a period of eight months from July 2021 to February 2022. Two hundred and thirty three study participants in both COVID recovered and non-infected groups (105 participants in infected group, 128 participants in non-infected group) were subjected to blood sampling at 6 months post-vaccination. Anti-SARS-CoV-2 IgG antibody test was done using Chemiluminescence method. Comparison of antibody levels between COVID-recovered and non-infected groups was made. Results were compiled and statistically analyzed using SPSS version 21. Out of 233 study participants, males were 183 (78%) while females were 50 (22%), mean age being 35.93 years ± 8.298. Mean Anti-SARS-CoV-2 S IgG levels among COVID-recovered group was 1342 U/ml and among non-infected group was 828 U/ml at 6 months post-vaccination. Mean antibody titers in COVID-19 recovered group are higher than in non-infected group at 6 months post-vaccination in both groups.

Pediatric population (aged 3-11 years) received primary inactivated SARS-CoV-2 vaccination prior to infection exhibiting robust humoral immune response following infected with Omicron variant: a study conducted in Beijing

Objective

Analysis of SARS-CoV-2 IgG antibody and neutralizing antibody levels following SARS-CoV-2 infection in children aged 3-11 years, comparing those who had received the inactivated SARS-CoV-2 vaccine to those who were unvaccinated prior to infection, provides evidence for public health centers in formulating vaccination strategies and control policies.

Methods

A study was conducted on children who visited the Children's Hospital, Capital Institute of Pediatrics from January 10, 2023 to March 31, 2023 (Beijing, China). Participants or their guardians completed a survey questionnaire providing information about their SARS-CoV-2 infection history and vaccination status. Serum samples were collected for testing of SARS-CoV-2 immunoglobulin G (IgG) and neutralizing antibodies (Nabs), which were performed using chemiluminescence immunoassay.

Results

The study included 1,504 children aged 3-11 years with previous SARS-CoV-2 infection history. Among the 333 unvaccinated children, the serum SARS-CoV-2 IgG antibody level was median 2.30 (IQR, 1.27-3.99). However, children received one dose (78 cases) and two doses (1093 cases) of the inactivated vaccine prior to infection showed significantly higher SARS-CoV-2 IgG antibody levels, with values of median 10.11 (IQR, 8.66-10.93) and median 10.58 (IQR, 9.79-11.07), respectively. As to the unvaccinated children, 70.3% (234/333) were negative for SARS-CoV-2 Nabs, which were less than 6.00AU/ml. The remaining 29.7% (99/333) showed relatively low levels of Nabs, ranging from 6.00 to 50.00AU/ml. In contrast, for children who had received two doses of vaccine prior to infection, an overwhelming 99.3% (1086/1093) exhibited high levels of Nas in the range of 100.00-120.00 AU/ml. Remarkably, these elevated Nab levels persisted for at least a period of 3 months post-infection in children who had received two doses of inactivated SARS-CoV-2 vaccine prior to infection, regardless of age or sex and vaccine manufacturer.

Conclusion

The administration of two doses of inactivated SARS-CoV-2 vaccine prior to infection has been shown to significantly enhance humoral immunity following SARS-CoV-2 infection in pediatric populations, producing adequate Nabs that persist at elevated levels for up to 3 months post-infection. For unvaccinated children who displayed weak humoral immunity following a primary natural infection, timely vaccination is recommended to bolster their immunization protection. The findings underscore the importance of vaccination in strengthening immune responses and protecting pediatric populations against SARS-CoV-2 infection.

Immunogenicity and safety assessment of a SARS-CoV-2 recombinant spike RBD protein vaccine (Abdala) in paediatric ages 3-18 years old: a double-blinded, multicentre, randomised, phase 1/2 clinical trial (ISMAELILLO study)

Background

COVID-19 in paediatric ages could result in hospitalizations and death. In addition, excluding children from vaccination could turn them into reservoirs of the SARS-COV-2. Safe and effective COVID-19 vaccines are urgently needed for large-scale paediatric vaccination. ISMAELILLO study aimed to evaluate safety and immunogenicity of two strengths of a new recombinant receptor-binding domain (RBD) protein vaccine (Abdala) in paediatric population.

Methods

A double-blinded, multicentre, randomised, phase 1/2 clinical trial was conducted in nine polyclinics in the province of Camagüey, Cuba. Healthy children and adolescents were stratified according to age (3-11 years old, or 12-18 years old) and they were randomly assigned (1:1; block size four) in two dosage level groups of vaccine to receive three intramuscular doses of 25 μg or 50 μg of RBD, 14 days apart. Main safety endpoint was analyzed as the percentage of serious adverse reactions during vaccination up to 28 days after the third dose (Day 56) in participants who received at least one dose vaccination. The primary immunogenicity endpoint assessed was seroconversion rate of anti-RBD IgG antibody at day 56. The immunogenicity outcomes were assessed in the per-protocol population. This trial is registered with Cuban Public Registry of Clinical Trials, RPCEC00000381.

Findings

Between July 15, 2021, and August 16, 2021, 644 paediatric subjects were screened, of whom 592 were enrolled after verifying that they met the selection criteria: firstly 88 were included in Phase 1 of the study and 504 who completed Phase 2. The vaccine was well tolerated. Injection site pain was the most frequently reported local event (143 [8·4%] of 1707 total doses applied), taking place in 66/851 (7·8%) in the 25 μg group and in 77/856 (9·0%) in the 50 μg. The most common systemic adverse event (AE) was headache: 23/851 (2·7%) in the 25 μg group and 19/856 (2·2%) in the 50 μg. Reactogenicity was mild or moderate in severity, represented in 75% of cases by local symptoms, completely resolved in the first 24-48 h. Twenty-eight days after the third dose, seroconversion anti-RBD IgG were observed in 98·2% of the children and adolescents (231/234) for the 50 μg group and 98·7% (224/228) for the 25 μg group without differences between both strength. The specific IgG antibody geometric mean titres (GMT) showed higher titres between participants who received Abdala 50 μg (231·3; 95% CI 222·6-240·4) compared to those who received 25 μg (126·7; 95% CI 121·9-131·7). The mean ACE2 inhibition %, were 59·4% for 25 μg, and for 50 μg, 72·9% (p < 0·01). Both strength elicited neutralising activity against the SARS-CoV-2, specifically (18·3; 95% CI 14·7-22·78) for Abdala 25 μg and (36·4; 95% CI 30·26-43·8) for 50 μg to the selected sample analyzed.

Interpretation

Abdala vaccine was safe and well tolerated at both antigenic strength levels tested in participants aged between 3 and 18 years. Regarding immunogenicity, Abdala Vaccine stimulated the production of specific IgG antibodies against the RBD of SARS-CoV-2 as well as the production of ACE2 inhibition titres and neutralising antibodies (Nab) in children and adolescents.

Funding

Centre for Genetic Engineering and Biotechnology (CIGB), Havana, Cuba.

ACE2 and a Traditional Chinese Medicine Formula NRICM101 Could Alleviate the Inflammation and Pathogenic Process of Acute Lung Injury

COVID-19 is a highly transmittable respiratory illness caused by SARS-CoV-2, and acute lung injury (ALI) is the major complication of COVID-19. The challenge in studying SARS-CoV-2 pathogenicity is the limited availability of animal models. Therefore, it is necessary to establish animal models that can reproduce multiple characteristics of ALI to study therapeutic applications. The present study established a mouse model that has features of ALI that are similar to COVID-19 syndrome to investigate the role of ACE2 and the administration of the Chinese herbal prescription NRICM101 in ALI. Mice with genetic modifications, including overexpression of human ACE2 (K18-hACE2 TG) and absence of ACE2 (mACE2 KO), were intratracheally instillated with hydrochloric acid. The acid intratracheal instillation induced severe immune cell infiltration, cytokine storms, and pulmonary disease in mice. Compared with K18-hACE2 TG mice, mACE2 KO mice exhibited dramatically increased levels of multiple inflammatory cytokines (IL-6 and TNF-α) in bronchoalveolar lavage fluid, histological evidence of lung injury, and dysregulation of MAPK and MMP activation. In mACE2 KO mice, NRICM101 could ameliorate the disease progression of acid-induced ALI. In conclusion, the established mouse model provided an effective platform for researchers to investigate pathological mechanisms and develop therapeutic strategies for ALI, including COVID-19-related ALI.

Dilemmas and options for COVID-19 vaccination in children

Over 16 million children have been detected positive for the coronavirus disease 2019 (COVID-19) in the United States since the outbreak of the pandemic. In general, children infected with severe acute respiratory syndrome coronavirus type 2 tend to have lighter symptoms than adults. However, in some cases, the infection can develop into severe forms, such as multisystem inflammatory syndrome in children. Moreover, long-term public health preventive interventions have had some negative effects on the physical and mental health of children. Given the important role that vaccination plays in reducing severe illness and mortality, it is essential for the efficient implementation of vaccination in the pediatric population. Nevertheless, parental distrust of vaccination, especially with regard to its safety and efficacy, hinders this process. Herein, we comprehensively summarize the available data on the safety and effectiveness of COVID-19 vaccine in children. The results show that the currently approved COVID-19 vaccine is safe and effective for children. Although two doses of vaccine in children seem insufficient to prevent Omicron infection, the booster dose provides enhanced protection against infection and severe illness. Most importantly, the bivalent vaccine has been approved for use in the pediatric population to extend the immune response to currently circulating Omicron variant. And the immune protection afforded to newborns after maternal vaccination appears to last only 6 months. Therefore, in the current situation where the rate of virus mutation is accelerating and the COVID-19 pandemic is still severe, it is crucial to extend vaccine protection to children over 6 months of age to weave a tighter safety net.

Acute Uveitis Following AstraZeneca COVID-19 Vaccination

PURPOSE

To report a case of bilateral acute uveitis following the first and subsequent doses of Oxford-AstraZeneca COVID-19 vaccination.

METHOD

A case report.

RESULTS

A 74-year-old Caucasian woman was presented with a one-day history of blurred vision, pain, photophobia, and redness in both eyes after receiving her first dose of the Oxford-AstraZeneca COVID-19 vaccine. Clinical evaluation confirmed bilateral anterior and intermediate uveitis six days later. Targeted diagnostic testing excluded infectious or autoimmune etiologies. After treatment with topical and oral corticosteroids, the patient had a resolution of symptoms with the recovery of visual function within seven weeks. Subsequently, she developed a recurrence of uveitis following the second dose of the Oxford-AstraZeneca COVID-19 vaccine, which required similar treatment, with slower tapering of corticosteroids over ten weeks. The patient had a full visual recovery.

CONCLUSION

Our case highlights the possibility of uveitis as an ocular complication of Oxford-AstraZeneca COVID-19 vaccination.

Receipt of COVID-19 vaccine in preterm-born children aged 3-7 in China

Objectives

To determine the COVID-19 vaccination rate in preterm-born children aged 3-7 in China and influential factors, identify vaccination-related adverse reactions, and clarify reasons behind parental refusal of vaccination to their children.

Methods

This cross-sectional study was conducted in parents of preterm-born children aged 3-7 in different regions of China through WeChat.

Results

Of 1,924 Chinese preterm-born children aged 3-7 included in this study, 1,552 (80.7%) had been vaccinated against COVID-19, with a higher vaccination rate in eastern China. Children older than 4 years, kids in kindergartens and primary schools, children living in eastern or western China, and children whose fathers had received at least one dose of a COVID-19 vaccine tended to be vaccinated against COVID-19 after adjusting for other covariates. Conversely, children living in urban areas, children whose annual family income was < 50,000 CNY or more than 300,000 CNY, premature children who underwent hospital transfers, and children with underlying diseases were less likely to get vaccinated. Adverse reactions occurred in 59/1,552 (3.8%) vaccinated children. Parents of 118/372 (31.7%) children expressed their concerns over adverse reactions to COVID-19 vaccination. Other reasons like the absence of information about the place where they could get vaccination were mentioned as well.

Conclusions

COVID-19 vaccination-related adverse reactions rarely occurred and most of them were mild among preterm-born children aged 3-7. Higher vaccination coverage can be achieved as parents are provided with more scientific data about benefits of vaccination, vaccination contraindications and precautions, and more information about vaccination sites.

Antibodies Capable of Enhancing SARS-CoV-2 Infection Can Circulate in Patients with Severe COVID-19

Antibody-dependent enhancement (ADE) has been shown previously for SARS-CoV-1, MERS-CoV, and SARS-CoV-2 infection in vitro. In this study, the first monoclonal antibody (mAb) that causes ADE in a SARS-CoV-2 in vivo model was identified. mAb RS2 against the SARS-CoV-2 S-protein was developed using hybridoma technology. mAb RS2 demonstrated sub-nanomolar affinity and ability to neutralize SARS-CoV-2 infection in vitro with IC₅₀ 360 ng/mL. In an animal model of SARS-CoV-2 infection, the dose-dependent protective efficacy of mAb RS2 was revealed. However, in post-exposure prophylaxis, the administration of mAb RS2 led to an increase in the viral load in the respiratory tract of animals. Three groups of blood plasma were examined for antibodies competing with mAb RS2: (1) plasmas from vaccinated donors without COVID-19; (2) plasmas from volunteers with mild symptoms of COVID-19; (3) plasmas from patients with severe COVID-19. It was demonstrated that antibodies competing with mAb RS2 were significantly more often recorded in sera from volunteers with severe COVID-19. The results demonstrated for the first time that in animals, SARS-CoV-2 can induce antibody/antibodies that can elicit ADE. Moreover, in the sera of patients with severe COVID-19, there are antibodies competing for the binding of an epitope that is recognized by the ADE-eliciting mAb.

A Review of Inactivated COVID-19 Vaccine Development in China: Focusing on Safety and Efficacy in Special Populations

The coronavirus disease 2019 (COVID-19) pandemic, caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has been widespread globally, and vaccination is critical for preventing further spread or resurgence of the outbreak. Inactivated vaccines made from whole inactivated SARS-CoV-2 virus particles generated in Vero cells are currently the most widely used COVID-19 vaccines, with China being the largest producer of inactivated vaccines. As a result, the focus of this review is on inactivated vaccines, with a multidimensional analysis of the development process, platforms, safety, and efficacy in special populations. Overall, inactivated vaccines are a safe option, and we hope that the review will serve as a foundation for further development of COVID-19 vaccines, thus strengthening the defense against the pandemic caused by SARS-CoV-2.

Comparison of the reactogenicity and immunogenicity between two-dose mRNA COVID-19 vaccine and inactivated COVID-19 vaccine followed by an mRNA vaccine in children aged 5-11 years

To compare the reactogenicity and immunogenicity between the two-dose mRNA COVID-19 vaccine regimen and one or two doses of inactivated vaccine followed by an mRNA vaccine regimen in healthy children between 5 and 11 years of age, a prospective cohort study was performed at King Chulalongkorn Memorial Hospital in Thailand between March to June 2022. Healthy children between 5 and 11 years of age were enrolled and received the two-dose mRNA COVID-19 vaccine (BNT162b2) regimen or the inactivated (CoronaVac) vaccine followed by the BNT162b2 vaccine regimen. In addition, healthy children who received two doses of BBIBP-CorV between 1 and 3 months prior were enrolled to receive a heterologous BNT162b2 as a third dose (booster). Reactogenicity was assessed by a self-reported online questionnaire. Immunogenicity analysis was performed to determine binding antibodies to wild-type SARS-CoV-2. Neutralizing antibodies to Omicron variants (BA.2 and BA.5) were tested using the focus reduction neutralization test. Overall, 166 eligible children were enrolled. Local and systemic adverse events which occurred within 7 days after vaccination were mild to moderate and well-tolerated. The two-dose BNT162b2, CoronaVac followed by BNT162b2, and two-dose BBIBP-CorV followed by BNT162b2 groups elicited similar levels of anti-receptor-binding domain (RBD) IgG. However, the two-dose BNT162b2 and two-dose BBIBP-CorV followed by BNT162b2 groups elicited higher neutralizing activities against the Omicron BA.2 and BA.5 variant than the CoronaVac followed by BNT162b2 group. The CoronaVac followed by BNT162b2 group elicited low neutralizing activities against the Omicron BA.2 and BA.5 variant. A third dose (booster) mRNA vaccine should be prioritized for this group.

Acceptability of COVID-19 vaccination in Chinese children aged 3-7 years with bronchopulmonary dysplasia

OBJECTIVES

To describe the status of coronavirus disease 2019 (COVID-19) vaccination with inactivated vaccines BBIBP-CorV and CoronaVac in Chinese children aged 3-7 years with bronchopulmonary dysplasia (BPD), and explore factors influencing vaccination and reasons for nonvaccination.

METHODS

This cross-sectional study involving parents of 397 BPD children aged 3-7 years was conducted through WeChat or follow-up telephone interviews using a standardized questionnaire form. Factors influencing COVID-19 vaccination were explored by using modified Poisson regression models.

RESULTS

The overall COVID-19 vaccination rate was 69.0% (95% confidence interval: 64.3%-73.4%). COVID-19 vaccination was less likely to be accepted in children whose mothers had a relatively high educational background (university and above), who lived in urban areas and had a low birth weight (<1 kg), a history of hospitalization for lung diseases in the past 12 months, and intellectual disability. Conversely, kindergarten students and children from families with an annual income of >300,000 CNY (≈ $\approx $ 41,400 USD) were more likely to accept vaccination. Adverse reactions occurred in 13/274 children (4.7%) within 10 days after vaccination. With respect to reasons of not accepting COVID-19 vaccination, 95 parents (77.2%) worried about the adverse reactions, and 17 parents (13.8%) refused vaccination on the excuse of not being convenient to go to the vaccination station or not knowing where to get the vaccines.

CONCLUSIONS

The COVID-19 vaccination rate in BPD children aged 3-7 years needs to be further improved in China. Continuous efforts are required to monitor postvaccination adverse reactions in BPD children, and make vaccination more convenient and accessible.

Effectiveness of an inactivated SARS-CoV-2 vaccine in children and adolescents: a large-scale observational study

Background

Policymakers urgently need evidence to adequately balance the costs and benefits of mass vaccination against COVID-19 across all age groups, including children and adolescents. In this study, we aim to assess the effectiveness of CoronaVac's primary series among children and adolescents in Chile.

Methods

We used a large prospective national cohort of about two million children and adolescents 6-16 years to estimate the effectiveness of an inactivated SARS-CoV-2 vaccine (CoronaVac) in preventing laboratory-confirmed symptomatic SARS-CoV-2 infection (COVID-19), hospitalisation, and admission to an intensive care unit (ICU) associated with COVID-19. We compared the risk of individuals treated with a complete primary immunization schedule (two doses, 28 days apart) with the risk of unvaccinated individuals during the follow-up period. The study was conducted in Chile from June 27, 2021, to January 12, 2022, when the SARS-CoV-2 Delta variant was predominant but other variants of concern were co-circulating, including Omicron. We used inverse probability-weighted survival regression models to estimate hazard ratios of complete immunization over the unvaccinated status, accounting for time-varying vaccination exposure and adjusting for relevant demographic, socioeconomic, and clinical confounders.

Findings

The estimated adjusted vaccine effectiveness for the inactivated SARS-CoV-2 vaccine in children aged 6-16 years was 74.5% (95% CI, 73.8-75.2), 91.0% (95% CI, 87.8-93.4), 93.8% (95% CI, 87.8-93.4) for the prevention of COVID-19, hospitalisation, and ICU admission, respectively. For the subgroup of children 6-11 years, the vaccine effectiveness was 75.8% (95% CI, 74.7-76.8) for the prevention of COVID-19 and 77.9% (95% CI, 61.5-87.3) for the prevention of hospitalisation.

Interpretation

Our results suggest that a complete primary immunization schedule with the inactivated SARS-CoV-2 vaccine provides effective protection against severe COVID-19 disease for children 6-16 years.

Funding

Agencia Nacional de Investigación y Desarrollo (ANID) Millennium Science Initiative Program and Fondo de Financiamiento de Centros de Investigación en Áreas Prioritarias (FONDAP).

Impact of nutraceuticals on immunomodulation against viral infections-A review during COVID-19 pandemic in Indian scenario

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) originated in Wuhan, China, in early December 2019 is a censorious global emergency after World War II. Research on the coronavirus uncovered essential information that aided in the development of the vaccine, and specific coronavirus disease 2019 (COVID-19) vaccines were later developed and were approved for usage in humans. But then, mutations in the coronavirus gave rise to new variants and questioned the vaccine's efficacy against them. On the other hand, the investigation of traditional medicine was also on its path to find a novel outcome against COVID-19. On a comparative analysis between India and the United States, India had low death rate and high recovery rate than the latter. The dietary regulation of immunity may be the factor that makes the above difference. The immunity gained from the regular diet of Indian culture nourishes Indian people with essential phytochemicals that support immunity and metabolism. Dietary phytochemicals or nutraceuticals possess antioxidant, anti-inflammatory, and anticancer properties, out of which our concern will be on immune-boosting phytochemicals from our daily nutritional supplements. In several case studies, dietary substance like lemon, ginger, and spinach was reported in the recovery of COVID-19 patients. Thus in this review, we discuss coronavirus and its available variants, vaccines, and the effect of nutraceuticals against the coronavirus. Further, we denote that the immunity of the Indian population may be high because of their diet, which adds natural phytochemicals to boost their immunity and metabolism.

BBIBP-CorV vaccination accelerates anti-viral antibody responses in heterologous Omicron infection: A retrospective observation study in Shanghai

OBJECTIVES

To investigate how BBIBP-CorV vaccination affecting antibody responses upon heterologous Omicron infection.

METHODS

440 Omicron-infected patients were recruited in this study. Antibodies targeting SARS-CoV-2 spike protein receptor binding domain (RBD) and nucleoprotein of both wild-type (WT) and Omicron were detected by ELISA. The clinical relevance was further analyzed.

RESULTS

BBIBP-CorV vaccinated patients exhibited higher anti-RBD IgG levels targeting both WT and Omicron than non-vaccinated patients at different stages. By using a 3-day moving average analysis, we found that BBIBP-CorV vaccinated patients exhibited the increases in both anti-WT and Omicron RBD IgG from the onset and reached the plateau at Day 8 whereas those in non-vaccinated patients remained low during the disease. Significant increase in anti-WT RBD IgA was observed only in vaccinated patients. anti-Omicron RBD IgA levels remained low in both vaccinated and non-vaccinated patients. Clinically, severe COVID-19 only occurred in non-vaccinated group. anti-RBD IgG and IgA targeting both WT and Omicron were negatively correlated with virus load, hospitalization days and virus elimination in vaccinated patients.

CONCLUSIONS

BBIBP-CorV vaccination effectively reduces the severity of Omicron infected patients. The existence of humoral memory responses established through BBIBP-CorV vaccination facilitates to induce rapid recall antibody responses when encountering SARS-CoV-2 variant infection.

Comparison of Biological, Pharmacological Characteristics, Indications, Contraindications, Efficacy, and Adverse Effects of Inactivated Whole-Virus COVID-19 Vaccines Sinopharm, CoronaVac, and Covaxin: An Observational Study

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is an emerging viral zoonotic illness that has developed a distinctive and threatening situation globally. Worldwide, many vaccines were introduced to fight against the COVID-19 pandemic. The present study aims to compare the bio-pharmacological characteristics, indications, contraindications, efficacy, and adverse effects of inactivated whole-virus COVID-19 vaccines, Sinopharm, CoronaVac, and Covaxin. Initially, 262 documents and 6 international organizations were selected. Finally, 41 articles, fact sheets, and international organizations were included. The data were recorded from the World Health Organization (WHO), Food and Drug Administration (FDA) USA, Web of Science, PubMed, EMBASE, and Scopus. The results demonstrated that these three inactivated whole-virus COVID-19 vaccines, Sinopharm, CoronaVac, and Covaxin, received emergency approval from the FDA/WHO, and all three of these vaccines are beneficial for the prevention of the COVID-19 pandemic. The Sinopharm vaccine has been recommended during pregnancy and for people of all age groups, and the CoronaVac and Covaxin vaccines are recommended for people over 18 years of age and older. These three vaccines have recommended intramuscular doses of 0.5 mL each, with a 3-4 week interval. These three vaccines can be stored in a refrigerator at +2 to +8 °C. The common adverse effects of these vaccines are pain at the injection site, redness, fatigue, headache, myalgias, general lethargy, body ache, arthralgia, nausea, chills, fever, and dizziness. The overall mean efficiency for the prevention of the COVID-19 disease is 73.78% for Sinopharm, 70.96% for CoronaVac, and 61.80% for Covaxin. In conclusion, all three inactivated whole-virus COVID-19 vaccines, Sinopharm, CoronaVac, and Covaxin, are beneficial for the prevention of the COVID-19 pandemic. However, evidence suggests that the overall impact of Sinopharm is slightly better than that of CoronaVac and Covaxin.

Challenges and Recent Advancements in COVID-19 Vaccines

Vaccination is the most effective method for the prevention of COVID-19 caused by SARS-CoV-2, which is still a global epidemic. However, the evolution of SARS-CoV-2 is so rapid that various variants, including the Alpha, Beta, Gamma, Delta, and Omicron variants, have emerged, lowering the protection rate of vaccines and even resulting in breakthrough infections. Additionally, some rare but severe adverse reactions induced by COVID-19 vaccines may raise safety concerns and hinder vaccine promotion; however, clinical studies have shown that the benefits of vaccination outweigh the risks caused by adverse reactions. Current vaccines approved with emergency use authorization (EUA) were originally adaptive for adults only, and infants, children, and adolescents are not included. New-generation vaccines are needed to overcome the challenges of limited adaptive age population, breakthrough infection (mainly due to virus variant emergencies), and critical adverse reactions. Fortunately, some advances in COVID-19 vaccines have been obtained regarding enlarged adaptive populations for clinical applications, such as the Pfizer/BioNTech vaccine and the Moderna vaccine. In this article, we provide a review on the challenges and recent advancements in COVID-19 vaccines. The development of next-generation COVID-19 vaccines should lay emphasis on the expansion of adaptive age populations in all individuals, the induction of immune responses to viral variants, the avoidance or alleviation of rare but potentially critical adverse reactions, and the discovery of subunit vaccines with adjuvants encapsulated in nanoparticles.

Studying the effects of booster shots and antibody responses to the SARS-CoV-2 vaccination over time in health personnel

Background

With the emergence of mutant versions that lead to continual spreading and recurrent infections of SARS-CoV-2, the COVID-19 vaccines can assist protection for high risk groups, particularly health workers. Even while booster shots have been widely used, longitude studies on immune responses in healthy subjects are uncommon.

Methods

Eighty-five healthcare workers who received the BBIBP-CorV vaccine were prospectively enrolled and monitored for up to ten months. Automated Pylon immunoassays were used to quantify total anti-SARS-CoV2 antibody levels (TAb), surrogate neutralization antibody levels (NAb), and antibody avidities over the course of the follow-up. Additionally, hematology analyses were performed.

Results

Pylon antibody testing revealed that every participant tested negative at the beginning, and 88.2% of them tested positive about 14 days after receiving their second dosage. The TAb levels and NAb levels peaked in 76.5% and 88.2% of the subjects, respectively, at the same time. Age was connected with the peak antibody levels, but not with gender, BMI, or baseline hematological factors. The positive rates and the antibody levels had already started to decline three months following the second injection. The antibody levels and avidities quickly increased following the booster doses to levels that were considerably greater than the peak antibody responses before to the booster shots. Hematology testing revealed no safety concerns with immunizations.

Conclusion

In healthy workers, the two doses of BBIBP-CorV were able to induce humoral immunity; however, 3 months following vaccination, the antibody levels started to decline. The BBIBP-CorV booster injections increase both the quantity and quality of antibodies, which gave support for utilizing booster doses to prolong the duration of the vaccine’s protective effects.

COVID-19 vaccination in children: a public health priority

OBJECTIVE

Covid-19 had a direct impact on children's health. The aim of this review was to analyze epidemiological and clinical data, the consequences of the pandemic, and vaccination aspects in this group.

SOURCES OF DATA

The searches were carried out from January 2020 to November 2022, in the MEDLINE databases (PubMed) and publications of the Brazilian Ministry of Health and the Brazilian Society of Pediatrics.

SUMMARY OF FINDINGS

Covid-19 has a mild presentation in most children; however, the infection can progress to the severe form and, in some cases, to MIS-C. The prevalence of the so-called long Covid in children was 25.24%. Moreover, several indirect impacts occurred on the health of children and adolescents. Vaccination played a crucial role in enabling the reduction of severe disease and mortality rates. Children and adolescents, as a special population, were excluded from the initial clinical trials and, therefore, vaccination was introduced later in this group. Despite its importance, there have been difficulties in the efficient implementation of vaccination in the pediatric population. The CoronaVac vaccines are authorized in Brazil for children over three years of age and the pediatric presentations of the Pfizer vaccine have shown significant effectiveness and safety.

CONCLUSIONS

Covid-19 in the pediatric age group was responsible for the illness and deaths of a significant number of children. For successful immunization, major barriers have to be overcome. Real-world data on the safety and efficacy of several pediatric vaccines is emphasized, and the authors need a uniform message about the importance of immunization for all children.

Safety and Tolerability of COVID-19 Vaccine in Children With Epilepsy: A Prospective, Multicenter Study

BACKGROUND

We designed this study to investigate the effects of the coronavirus disease 2019 (COVID-19) vaccine on epileptic seizures, as well as its adverse effects, in children with epilepsy (<18 years).

METHODS

This anonymous questionnaire study involved a multicenter prospective survey of outpatients and inpatients with epilepsy (＜18 years) registered in epilepsy clinics in eight hospitals in six cities of Shandong Province.

RESULTS

A total of 224 children with epilepsy were included in the study. Fifty of them experienced general adverse events after vaccination. The most common local adverse events were pain or tenderness at the injection site. The most common systemic adverse effects were muscle soreness and headache. No severe adverse events were reported. There were no significant differences in the number of antiseizure medications (P = 0.459), gender (P = 0.336), etiology (P = 0.449), age (P = 0.499), duration of disease (P = 0.546), or seizure type (P = 0.475) between the patients with and without general adverse events. We found that the risk of seizure after vaccination was decreased in children who were seizure free for more than six months before vaccination. There was no significant difference in the number of seizures during the first month before vaccination, the first month after the first dose, and the first month after the second dose (P = 0.091).

CONCLUSION

The benefits of vaccination against COVID-19 outweighed the risks of seizures/relapses and severe adverse events after vaccination for children with epilepsy.

A comparative study of the COVID-19 vaccine efficacy among cancer patients: mRNA versus non-mRNA

BACKGROUND

Cancer patients have an increased risk of a severe COVID-19 infection with higher mortality rate. This study aimed to analyze the levels of anti-SARS-CoV-2 S-RBD IgG and NAB among cancer patients who were vaccinated with COVID-19 vaccines, either with BNT162b2, mRNA-1273, AZD1222/ChAdOx1nCoV-19, or Coronavac/BBIBP-CorV vaccines.

METHOD

A cross-sectional study was conducted among subjects with either solid or hematological cancers who had received two doses of either mRNA or non-mRNA vaccines within 6 months. The levels of anti-SARS-CoV-2 S-RBD IgG and NAb were analyzed using the Mindray Immunoassay Analyzer CL-900i. Statistical analysis was conducted using mean comparison and regression analysis.

RESULT

The mRNA-1273 vaccine had the highest median levels of S-RBD IgG and NAb, followed by BNT162b, ChAdOx1nCoV-19, and BBIBP-CorV/Coronavac. The levels of S-RBD IgG and NAb in subjects vaccinated with mRNA vaccines were significantly higher than those of non-mRNA vaccines when grouped based on their characteristics, including age, type of cancer, chemotherapy regimen, and comorbidity (p<0.05). Furthermore, the S-RBD IgG and NAb levels between the subjects vaccinated with non-mRNA vaccines and the subjects vaccinated with mRNA vaccines were significantly different (p<0.05). However, there was no significant difference between the same types of vaccines. This study demonstrated a very strong correlation between the level of S-RBD IgG and the level of NAb (R = 0.962; p<0.001). The level of anti-SARS-CoV-2 S-RBD IgG was consistently higher compared to the level of NAb.

CONCLUSIONS

Generally, mRNA vaccines produced significantly higher anti-SARS-CoV-2 S-RBD IgG and NAb levels than non-mRNA vaccines in cancer subjects.

A DNA Vaccine Encoding the Full-Length Spike Protein of Beta Variant (B.1.351) Elicited Broader Cross-Reactive Immune Responses against Other SARS-CoV-2 Variants

The SARS-CoV-2 pandemic remains an ongoing threat to global health with emerging variants, especially the Omicron variant and its sub-lineages. Although large-scale vaccination worldwide has delivered outstanding achievements for COVID-19 prevention, a declining effectiveness to a different extent in emerging SARS-CoV-2 variants was observed in the vaccinated population. Vaccines eliciting broader spectrum neutralizing antibodies and cellular immune responses are urgently needed and important. To achieve this goal, rational vaccine design, including antigen modeling, screening and combination, vaccine pipelines, and delivery, are keys to developing a next-generation COVID-19 vaccine. In this study, we designed several DNA constructs based on codon-optimized spike coding regions of several SARS-CoV-2 variants and analyzed their cross-reactive antibodies, including neutralizing antibodies, and cellular immune responses against several VOCs in C57BL/6 mice. The results revealed that different SARS-CoV-2 VOCs induced different cross-reactivity; pBeta, a DNA vaccine encoding the spike protein of the Beta variant, elicited broader cross-reactive neutralizing antibodies against other variants including the Omicron variants BA.1 and BA.4/5. This result demonstrates that the spike antigen from the Beta variant potentially serves as one of the antigens for multivalent vaccine design and development against variants of SARS-CoV-2.

Immunological Findings in a Group of Individuals Who Were Poor or Non-Responders to Standard Two-Dose SARS-CoV-2 Vaccines

Coronavirus disease (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has been declared a pandemic. However, data on the poor or non-responders to SARS-CoV-2 vaccines in the general population are limited. The objective of this study was to comprehensively compare the immunological characteristics of poor or non-responders to SARS-CoV-2 vaccines in the 18-59-year group with those in the ≥60-year group using internationally recognized cut-off values. The main outcome was effective seroconversion characterized by an anti-SARS-CoV-2 spike IgG level of at least a four-fold increase from baseline. Profiling of naïve immune cells was analyzed prior to vaccination to demonstrate baseline immunity. The outcomes of effective seroconversion in patients aged 18-59 years with those in patients aged ≥60 years were compared. The quantitative level of anti-spike IgG was significantly lower in individuals aged ≥60 and men aged 18-59 years. There were 7.5% of poor or non-responders among the 18-59 years and 11.7% of poor or non-responders in the ≥60 years using a four-fold increase parameter. There were 37.0-58.1% with low lymphocyte count (<1000/mm³), 33.3-45.2% with low CD4 cell counts (<500/mm³), and 74.1-96.8% with low B cell counts (<100/mm³) in the non-seroconversion group. An individual with an anti-SARS-CoV-2 spike IgG titer below 50 BAU/mL might be considered a poor or non-responder between 14 and 90 days after the last vaccine dose. Booster vaccination or additional protective measures should be recommended to poor or non-responders as soon as possible to reduce disease severity and mortality.

Neutralizing Antibodies as Predictors of Vaccine Breakthrough Infection in Healthcare Workers Vaccinated with or without a Heterologous Booster Dose: A Cohort Study during the Third COVID-19 Wave in Peru

We evaluated neutralizing antibody (NAbs) levels as a protective factor against vaccine breakthrough infection (VBI) in healthcare workers (HCWs) during the third COVID-19 wave in Peru. This retrospective cohort study employed the information from a private laboratory in Lima (Peru) of HCW who received only two BBIBP-CorV vaccines or (additionally) a heterologous booster with BNT162b2. We evaluated the association between the VBI and the levels of NAbs at 21, 90, 180, and 210 days after the BBIBP-CorV second dose. NAbs were calculated with the cPass™ SARS-CoV-2 Neutralization Antibody Detection kit (surrogate virus neutralization test (sVNT)) and the Elecsys^® anti-SARS-CoV-2 S Test. Of the 435 HCW evaluated, 31.72% had an infection previous to vaccination, 68.28% received a booster dose, and 23.21% had a VBI during the third wave. The variables associated with a lower risk of VBI were male sex (aRR: 0.43) and those who had (180 days after BBIBP-CorV inoculation) NAbs levels ≥ 60% (aRR: 0.58) and ≥90% (aRR: 0.59) on cPass™, and ≥500 with Elecsys^® (aRR: 0.58). HCW whose NAbs persisted at higher levels six months after the BBIBP-CorV showed a lower risk of suffering from a VBI during the third COVID-19 wave.

Homologous booster immunization with an inactivated vaccine induced robust antibody response in healthcare workers: A retrospective study

Coronavirus Disease 2019 (Covid-19) severely impacted the health, society, and economy around the world. With declining protective efficacy of primary vaccination and the spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants, a Covid-19 booster vaccination is being fully implemented globally. Many people received three doses of BBIBP-CorV inactivated vaccine in China and other developing countries. However, the antibody response and immune persistence of the homologous BBIBP-CorV booster vaccination is yet to be thoroughly evaluated, as previous studies focused within one month after the third dose. In this study, 97 participants were enrolled to analyze the antibody response and immune persistence within 6 months as well as the safety within 7 days after the third-dose of homologous BBIBP-CorV inactivated vaccine. The seroconversion rate for total antibody against the receptor binding domain (RBD) of the SARS-CoV-2 spike (S) protein were both 100% at month 1 and month 6 after the third dose. The IgG against the RBD of the SARS-CoV-2 S protein seroconversion rate increased from 42.27% before the third dose to 100% 1 month after the third dose and then slightly decreased to 98.97% 5 months later. Positive IgM against the RBD of the SARS-CoV-2 S protein was rare and was observed in only one participant at month 1 after the third dose. The neutralizing antibody levels at month 1 and month 6 after the third dose increased 63.32-fold and 13.16-fold compared with those before the third dose, and the positive rate for neutralizing antibody was still 100% at month 6 after the third dose. Importantly, the antibody responses induced by the vaccine and immune persistence were not affected by sex or age. No serious adverse reactions were reported. Total antibody and IgG against the RBD of the SARS-CoV-2 S protein were highly correlated with neutralizing antibody, suggesting that total antibody and IgG against the RBD of the SARS-CoV-2 S protein could be used as predictors for neutralizing antibody. In conclusion, the third dose of homologous BBIBP-CorV inactivated vaccine induced a robust antibody response and moderate immune persistence. These finding are of great significance for development future vaccination strategies.

COVID-19 Vaccines-All You Want to Know

The severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) pandemic has led to an unprecedented public health crisis. The collective global response has led to production of multiple safe and effective vaccines utilizing novel platforms to combat the virus that have propelled the field of vaccinology forward. Significant challenges to universal vaccine effectiveness remain, including immune evasion by SARS-CoV-2 variants, waning of immune response, inadequate knowledge of correlates of protection, and dosing in special populations. This review serves as a detailed evaluation of the development of the current SARS-CoV-2 vaccines, their effectiveness, and challenges to their deployment as a preventive tool.

Humoral and cellular immunity of two-dose inactivated COVID-19 vaccination in Chinese children: A prospective cohort study

Children are the high-risk group for COVID-19, and in need of vaccination. However, humoral and cellular immune responses of COVID-19 vaccine remain unclear in vaccinated children. To establish the rational immunization strategy of inactivated COVID-19 vaccine for children, the immunogenicity of either one dose or two doses of the vaccine in children was evaluated. A prospective cohort study of 322 children receiving inactivated COVID-19 vaccine was established in China. The baseline was conducted after 28 days of the first dose, and the follow-up was conducted after 28 days of the second dose. The median titers of receptor binding domain (RBD)-IgG, and neutralizing antibody (NAb) against prototype strain and Omicron variant after the second dose increased significantly compared to those after the first dose (first dose: 70.0, [interquartile range, 30.0-151.0] vs. second dose: 1261.0 [636.0-2060.0] for RBD-IgG; 2.5 [2.5-18.6] vs. 252.0 [138.6-462.1] for NAb against prototype strain; 2.5 [2.5-2.5] vs. 15.0 [7.8-26.5] for NAb against Omicron variant, all p < 0.05). The flow cytometry results showed that the first dose elicited SARS-CoV-2 specific cellular immunity, while the second dose strengthened SARS-CoV-2 specific IL-2⁺ or TNF-α⁺  monofunctional, IFN-γ⁺ TNF-α⁺  bifunctional, and IFN-γ^- IL-2⁺ TNF-α⁺ multifunctional CD4⁺ T cell responses (p < 0.05). Moreover, SARS-CoV-2 specific memory T cells were generated after the first vaccination, including the central memory T cells and effector memory T cells. The present findings provide scientific evidence for the vaccination strategy of the inactive vaccines among children against COVID-19 pandemic.

Immunogenicity assessment of elder hepatocellular carcinoma patients after inactivated whole-virion SARS-CoV-2 vaccination

BACKGROUND

Research on immunogenicity after 3rd SARS-CoV-2 vaccine in elder hepatocellular carcinoma (HCC) was limited. This study aimed to investigate the efficacy and influencing factors of inactivated SARS-CoV-2 vaccine in elder HCC.

RESEARCH DESIGN AND METHODS

We assessed total antibodies, anti-RBD IgG, and neutralizing antibodies (NAb) toward SARS-CoV-2 wild type (WT) as well as BA.4/5 in 304 uninfected HCC, 147 matched healthy control (HC), and 53 SARS-CoV-2 infected HCC, all aged over 60 years. The levels of antibodies were compared in the period 7-90, 91-180, and >180 days after 2nd or 3rd vaccination, respectively.

RESULTS

HCC had lower seropositivity than HC after 2nd dose (total antibodies, 64% vs. 92%, P < 0.0001; anti-RBD IgG, 50% vs. 77%, P < 0.0001). But 3rd dose can efficaciously close the gap (total antibodies, 96% vs. 100%, P = 0.1212; anti-RBD IgG: 87% vs. 87%, P > 0.9999). Booster effect of 3rd dose can persist >180 days in HCC (2nd vs. 3rd: total antibodies, 0.60 vs. 3.20, P < 0.0001; anti-RBD IgG, 13.86 vs. 68.85, P < 0.0001; WT NAb, 11.70 vs. 22.47, P < 0.0001). Vaccinated HCC had more evident humoral responses than unvaccinated ones after infection (total antibodies: 3.85 vs. 3.20, P < 0.0001; anti-RBD IgG: 910.92 vs. 68.85, P < 0.0001; WT NAb: 96.09 vs. 22.47, P < 0.0001; BA.4/5 NAb: 86.53 vs. 5.59, P < 0.0001).

CONCLUSIONS

Our findings highlight the booster effect and protective role of 3rd dose. Our results could provide a theoretical foundation for informing decisions regarding SARS-CoV-2 vaccination in elder HCC.

Open-label phase I/II clinical trial of SARS-CoV-2 receptor binding domain-tetanus toxoid conjugate vaccine (FINLAY-FR-2) in combination with receptor binding domain-protein vaccine (FINLAY-FR-1A) in children

OBJECTIVES

To evaluate a heterologous vaccination scheme in children 3-18 years old (y/o) combining two SARS-CoV-2r- receptor binding domain (RBD)protein vaccines.

METHODS

A phase I/II open-label, adaptive, and multicenter trial evaluated the safety and immunogenicity of two doses of FINLAY-FR-2 (subsequently called SOBERANA 02) and the third heterologous dose of FINLAY-FR-1A (subsequently called SOBERANA Plus) in 350 children 3-18 y/o in Havana Cuba. Primary outcomes were safety (phase I) and safety/immunogenicity (phase II) measured by anti-RBD immunoglobulin (Ig)G enzyme-linked immunoassay (ELISA), molecular and live-virus neutralization titers, and specific T-cells response. A comparison with adult immunogenicity and predictions of efficacy were made based on immunological results.

RESULTS

Local pain was the unique adverse event with frequency >10%, and none was serious neither severe. Two doses of FINLAY-FR-2 elicited a humoral immune response similar to natural infection; the third dose with FINLAY-FR-1A increased the response in all children, similar to that achieved in vaccinated young adults. The geometric mean (GMT) neutralizing titer was 173.8 (95% confidence interval [CI] 131.7; 229.5) vs Alpha, 142 (95% CI 101.3; 198.9) vs Delta, 24.8 (95% CI 16.8; 36.6) vs Beta and 99.2 (95% CI 67.8; 145.4) vs Omicron.

CONCLUSION

The heterologous scheme was safe and immunogenic in children 3-18 y/o.

TRIAL REGISTRY

https://rpcec.sld.cu/trials/RPCEC00000374.

Safety, Efficacy, and Immunogenicity of Varying Types of COVID-19 Vaccines in Children Younger Than 18 Years: An Update of Systematic Review and Meta-Analysis

Vaccination is one of the most effective measures for children as the epidemic progresses. However, there is a significant research gap in the meta-analysis of the COVID-19 vaccines for children younger than 18 years. This study is a comprehensive review of different COVID-19 vaccines. Published articles were retrieved from PubMed, Embase, and the Cochrane Library. Twelve randomized controlled trials (RCTs) of COVID-19 vaccines were included in the review until 21 October 2022. Most local and systemic adverse reactions were predominantly mild to moderate in severity and disappeared quickly after different types of vaccines. The subunit vaccine had the highest safety. The significant risk was lower in the subunit vaccine group after the initial (RR 1.66, 95% CI 1.26-2.17, p = 0.0003) and booster vaccination (RR 1.40, 95% CI 1.02-1.92, p = 0.04). Younger children had a more outstanding safety profile in the mRNA and inactivated vaccine groups. The humoral immune response was proportional to the number of doses in the inactivated and the adenovirus vaccine groups, and the strength of immunogenicity was negatively correlated with age in the inactivated vaccine. The mRNA and the subunit vaccines provided satisfactory prevention against COVID-19, especially seven days after the booster dose. However, more research and longer-term follow-up are needed to assess the duration of immune responses, efficacy, and safety.

An Immunological Review of SARS-CoV-2 Infection and Vaccine Serology: Innate and Adaptive Responses to mRNA, Adenovirus, Inactivated and Protein Subunit Vaccines

The coronavirus disease 2019 (COVID-19) pandemic is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus, which is defined by its positive-sense single-stranded RNA (ssRNA) structure. It is in the order Nidovirales, suborder Coronaviridae, genus Betacoronavirus, and sub-genus Sarbecovirus (lineage B), together with two bat-derived strains with a 96% genomic homology with other bat coronaviruses (BatCoVand RaTG13). Thus far, two Alphacoronavirus strains, HCoV-229E and HCoV-NL63, along with five Betacoronaviruses, HCoV-HKU1, HCoV-OC43, SARS-CoV, MERS-CoV, and SARS-CoV-2, have been recognized as human coronaviruses (HCoVs). SARS-CoV-2 has resulted in more than six million deaths worldwide since late 2019. The appearance of this novel virus is defined by its high and variable transmission rate (RT) and coexisting asymptomatic and symptomatic propagation within and across animal populations, which has a longer-lasting impact. Most current therapeutic methods aim to reduce the severity of COVID-19 hospitalization and virus symptoms, preventing the infection from progressing from acute to chronic in vulnerable populations. Now, pharmacological interventions including vaccines and others exist, with research ongoing. The only ethical approach to developing herd immunity is to develop and provide vaccines and therapeutics that can potentially improve on the innate and adaptive system responses at the same time. Therefore, several vaccines have been developed to provide acquired immunity to SARS-CoV-2 induced COVID-19-disease. The initial evaluations of the COVID-19 vaccines began in around 2020, followed by clinical trials carried out during the pandemic with ongoing population adverse effect monitoring by respective regulatory agencies. Therefore, durability and immunity provided by current vaccines requires further characterization with more extensive available data, as is presented in this paper. When utilized globally, these vaccines may create an unidentified pattern of antibody responses or memory B and T cell responses that need to be further researched, some of which can now be compared within laboratory and population studies here. Several COVID-19 vaccine immunogens have been presented in clinical trials to assess their safety and efficacy, inducing cellular antibody production through cellular B and T cell interactions that protect against infection. This response is defined by virus-specific antibodies (anti-N or anti-S antibodies), with B and T cell characterization undergoing extensive research. In this article, we review four types of contemporary COVID-19 vaccines, comparing their antibody profiles and cellular aspects involved in coronavirus immunology across several population studies.