The Importance of Advancing Severe Acute Respiratory Syndrome Coronavirus 2 Vaccines in Children

Immunogenicity and safety of an inactivated COVID-19 vaccine (CoronaVac®) co-administered with an inactivated enterovirus type 71 vaccine (Inlive®): A phase 4, randomized, controlled trial

TRIAL REGISTRATION NUMBER

NCT04993365 (ClinicalTrials.gov).

Factors Associated with Adverse Outcomes among SARS-CoV-2 Positive Children in a Tertiary Government COVID-19 Referral Hospital in the Philippines

Background and Objective

Pediatric COVID-19 epidemiology and factors associated with adverse outcomes - mortality, need for invasive mechanical ventilation, and ICU admission, are largely unstudied. We described the clinico-demographic characteristics of Filipino pediatric COVID-19 patients and determined the factors associated with adverse outcomes.

Methods

This is a retrospective cohort study of 180 hospitalized SARS-CoV-2-confirmed cases 0-18 years old from April 2020 to August 2021 in a tertiary COVID-19 referral hospital in Manila, National Capital Region. Crude associations were determined using chi-squared or Fisher's exact tests; and medians were compared using the Mann-Whitney test. Factors predictive of mortality were determined using Cox proportional hazards regression analysis. The survivor functions were depicted in graphs.

Results

About 41.67% had mild disease, 58.33% were males, 39.4% aged 0-4 years, and 69.44% had at least one comorbidity. About 9.44% died (adjusted 9.2 persons per 1000 patient-days, 95% CI 5.5%-15.2%), 17.78% needed invasive mechanical ventilation, and 20% needed ICU admission. Independently, severe-critical COVID-19 (HRc 11.51, 95% CI 3.23, 41.06), retractions (HRc 10.30, 95% CI 3.27, 32.47), alar flaring (HRc 4.39, 95% CI 1.53, 12.58), cyanosis (HRc 4.39, 95% CI 1.72, 14.11), difficulty of breathing (HRc 7.99, 95% CI 2.25, 28.71), poor suck/appetite (HRc 4.46, 95% CI 1.59, 12.40), ferritin (HRc 1.01, 95% CI 1.00, 1.01), IL-6 (HRc 1.01, 95% CI 1.00, 1.01), aPTT (HRc 1.05, 95% CI 1.01, 1.10), IVIg (HRc 4.00, 95% CI 1.07, 14.92) and corticosteroid (HRc 6.01, 95% CI 2.04, 17.67) were significant hazards for mortality. In adjusted Cox analysis, only retractions (HRa 34.96, 95% CI 3.36, 363.79), seizure (HRa 9.98, 95% CI 1.76, 56.55), and corticosteroids (HRa 8.21, 95% CI 1.12, 60.38) were significantly associated with mortality while alar flaring appeared to be protective (HRa 0.10, 95% CI 0.01, 0.95). Several clinical characteristics were consistently associated with adverse outcomes.

Conclusions

Majority of hospitalized pediatric COVID-19 patients were very young, males, had mild disease, and had at least one comorbidity. Mortality, invasive mechanical ventilation, and ICU admission were relatively low. Except for alar flaring which appeared to be protective, retractions, seizure, and use of corticosteroids were associated with adverse outcomes.

Emergency Departments: An Underutilized Resource for Expanding COVID-19 Vaccine Coverage in Children

COVID-19 vaccine (CV) acceptance rates remain suboptimal in children. Emergency departments (EDs) represent a unique opportunity to improve vaccination rates, particularly in underserved children. Little is known about the presence or reach of CV programs in US EDs. We assessed, via a cross-sectional survey of pediatric ED physicians, the number of EDs offering CVs to children, the approximate numbers of vaccines administered annually, and the perceived facilitators/barriers to vaccination. The proportion of EDs offering CVs is reported. Chi-square tests compared facilitators and barriers among frequent vaccinators (≥50 CVs/year), infrequent vaccinators (<50 CVs/year), and non-vaccinators. Among 492 physicians from 166 EDs, 142 responded (representing 61 (37.3%) EDs). Most EDs were in large, urban, academic, freestanding children's hospitals. Only 11 EDs (18.0%) offer ≥1 CV/year, and only two (18.2%) of these gave ≥50 CVs. Common facilitators of vaccination included the electronic health record facilitation of vaccination, a strong provider/staff buy-in, storage/accessibility, and having a leadership team or champion. Barriers included patient/caregiver refusal, forgetting to offer vaccines, and, less commonly, a lack of buy-in/support and the inaccessibility of vaccines. Many (28/47, 59.6%) EDs expressed interest in establishing a CV program.

Personal risk or societal benefit? Investigating adults' support for COVID-19 childhood vaccination

Parental hesitancy poses a serious threat to the success of the COVID-19 childhood vaccination campaign. We investigate whether adults' opinions on childhood vaccination can be influenced via two survey experiments in Italy (n = 3,633 participants) and the UK (n = 3,314 participants). Respondents were randomly assigned to: a "risk treatment" that highlighted the potential risks of COVID-19 to a child, a "herd immunity treatment" that emphasized the community benefits of pediatric vaccination, or a control message. Participants' probability of supporting COVID-19 childhood vaccination was then assessed on a 0-100 scale. We find that the "risk treatment" reduced the proportion of Italian parents strongly against vaccination by up to 29.6 %, while increasing the proportion of neutral parents by up to 45.0 %. The "herd immunity treatment", instead, was only effective among non-parents, resulting in a lower proportion of individuals against pediatric vaccination and a higher proportion of individuals in favor (both shifted by around 20 %).

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.

Do we need to vaccinate every child against COVID-19: What evidence suggests-A systematic review of opinions

It is still debatable whether all children should receive the COVID-19 vaccine. The comparatively mild cases and low risk of COVID-19 in children compared to adults, as well as the lack of clarity on the relative effects of the disease and vaccine, indicate that the risk-benefit ratio of vaccination in children is more nuanced. To consider and highlight the complexity of policy decisions regarding COVID-19 vaccination in children, we outlined the points regarding for and against vaccination of children against COVID-19 in this systemic review. Using Medical Search Headings (MeSH) terms and keywords, we searched PubMed, PubMed Central, Scopus, and Google Scholar. The primary search term was COVID-19 vaccination (all synonyms), factors (all synonyms), and among children (all synonyms). A total of 367 articles were searched. Finally, 64 articles met the inclusion criteria and were included in the review. The major theme/tone of 28 (43.75%) articles was in favor of children's COVID vaccination, and they were highlighting the positive factors, whereas the major theme/tone of 20 (31.25%) articles was against it. Approximately 16 (25.0%) articles were in a neutral position. Major factors highlighted by articles in favor of childhood COVID vaccination were as follows: the increasing rate of disease burden (29 articles), prevention of interruption of academic activities of children or school reopening (24 articles), and a role in defense against COVID infection (21 articles). Major factors against childhood vaccination were as follows: mild infection among children (27 articles), ethical concerns and legal problems regarding the consent of minors (17 articles), and vaccine hesitancy among parents for childhood vaccination (11 articles). Whereas, factors of uncertainty were the role in the reduction of community transmission (19 articles), protection against MIS-C (10 articles), and defense against long COVID (7 articles). Considering all the factors of COVID-19 disease progression among children, a cautious approach will be essential before proceeding with COVID-19 vaccination in children.

Variables Associated With COVID-19 Vaccination Among Israeli Adolescents and the Need for Targeted Interventions

BACKGROUND

We aimed to elucidate variables associated with coronavirus disease 2019 (COVID-19) vaccine compliance in adolescents and devise targeted interventions. Our secondary aim was to compare the rates of severe acute respiratory syndrome coronavirus 2 infection, hospitalizations and deaths between vaccinated and unvaccinated adolescents.

METHODS

A retrospective review of electronic medical records was performed on all adolescents 12-17 years of age registered at Clalit Health District in Israel during January 1, 2021, to November 18, 2021, with characterization by vaccination status against COVID-19. Univariate and multivariable analyses were employed to identify predictors of vaccination.

RESULTS

Of the 43,919 subjects included in the study, 28,207 (64.2%) were vaccinated. Non-ultraorthodox Jewish adolescents had a higher vaccination rate than the minorities Arabs or ultraorthodox Jews (72.5%, 66.2% and 40.5%, respectively, P &lt; 0.001). Adolescents of high socioeconomic status had nearly 2-fold higher vaccination rates than those of low socioeconomic status (80.4% vs 42.3%; P &lt; 0.0001). Adolescents 16-17 years old had a higher rate of COVID-19 vaccination than those 12-15 years old (72.5% vs 60.6%, P &lt; 0.001), as were girls versus boys (64.7% vs 63.8%, P = 0.047). Multivariate analysis identified 3 independent variables that were significantly ( P &lt; 0.001) associated with low vaccination: ultraorthodox sector, Arab population, and underlying obesity (hazard rations 0.42, 0.72 and 0.84, respectively). Vaccination was significantly associated with reduced severe acute respiratory syndrome coronavirus 2 infection, hospitalization and death ( P &lt; 0.001).

CONCLUSION

This study highlights several pediatric populations with low COVID-19 vaccine compliance. Targeted interventions aimed at these populations are suggested with consideration of their special cultural, social and societal characteristics.

Adverse events following immunization of COVID-19 vaccine among children aged 6-11 years

Introduction

Starting in December 2021, the Indonesian Government has recommended inactivated SARS-CoV-2 vaccine (CoronaVac) for children aged 6-11 years. This study aims to determine the prevalence and determinant factors of adverse events following immunization (AEFI) of the first dose and the second dose of the COVID-19 vaccine among children aged 6-11 years old.

Materials and methods

We conducted a cross-sectional study in Bantul District, Yogyakarta, Indonesia, in February-March 2022. Data were collected by trained interviews with 1,093 parents of children 6-11 years old who received the first dose and the second dose of the COVID-19 vaccine. Data were analyzed with chi-square and logistic regression.

Results

The prevalence of AEFI in the first dose of the COVID-19 vaccine was 16.7%, while the second dose was 22.6%. The most common symptoms of AEFI at the first dose were local site pain and fever, while at the second dose were cough and cold. Determinants of AEFI of COVID-19 vaccination among children were girls with OR 1.31 (95% CI 1.0-1.7; P 0.04), mass-setting of vaccination with OR 0.70 (95% CI 0.5-0.9; P 0.01), the history of AEFI in childhood vaccination with OR 1.63 (95% CI 1.2-2.2; P < 0.01) and administering other vaccines within 1 month before COVID-19 vaccination, with OR 5.10 (95% CI 2.1-12.3 P < 0.01).

Conclusion

The prevalence of AEFI in the first and the second dose of inactivated COVID-19 vaccine was comparable to that reported in the clinical trial study and the communities. Risk communication should be provided to the child and their parents regarding the risk of mild AEFI of the COVID-19 vaccine, especially for children with a history of AEFI in childhood vaccination and who received other vaccines containing the same adjuvant with CoronaVac within 1 month. A mass-setting of vaccination should be taken as an advantage to educate parents about the risk of AEFI and also about the reporting pathways.

Clinician perspectives on pediatric COVID-19 vaccination: A qualitative study in central and western, Massachusetts

We explored perspectives of clinicians in central and western Massachusetts about efforts to vaccinate pediatric patients against COVID-19 as well as best practices and challenges for vaccine delivery. We conducted semi-structured qualitative interviews (n = 16) with family practice and pediatric clinicians between late October and early December 2021. Our interviews addressed: process for vaccination and vaccine promotion, parental receptivity to COVID-19 vaccination, receptivity to other pediatric vaccines, resources needed to support vaccine promotion, and best practices developed to encourage hesitant parents. Using a multi-prong recruitment strategy we invited clinicians to participate in telephone interviews, which were audio-recorded and transcribed. We used rapid qualitative analysis to produce summary templates for each interview which were ultimately combined into a matrix summary. The majority of participants (n = 10) were offering the vaccine in their own clinics, while the remainder cited challenges related to staffing, logistics, and space that prevented them from offering the vaccine. Clinicians reported parents fall into three groups: vaccine-accepting, hesitant but potentially accepting, and refusers. Strategies they identified that worked to encourage hesitant parents were sharing personal vaccine stories, acknowledging parents' fears about the vaccine, and being persistent with the most hesitant parents. Yet resources are needed including educational materials and training in how to have these conversations. While challenges related to staffing and space will be difficult to overcome for clinics to be able to offer vaccination on-site, our results highlight the importance of developing effective messaging strategies and training clinicians in how to integrate them into routine practice.

Immunogenicity of a Fractional Dose of mRNA BNT162b2 COVID-19 Vaccine for Primary Series and Booster Vaccination among Healthy Adolescents

Primary series vaccination with BNT162b2 followed by a booster 5 months later has been recommended for healthy adolescents. We aimed to describe the immunogenicity in a fractional dose of BNT162b2. Adolescents aged 12–18 years were randomized into six arms for primary series administration: 3wPZ30/30 (reference group), 3wPZ30/20, 3wPZ20/20, 6wPZ30/30, 6wPZ30/20, and 6wPZ20/20 μg. A booster was given at 5 months after the second dose using either 10 or 15 μg of BNT162b2. Immunogenicity following vaccination was determined by IgG against receptor-binding domain (anti-S-RBD IgG; BAU/mL), surrogate virus neutralization test (sVNT; %inhibition) and pseudovirus neutralization (pVNT;ID₅₀) against Omicron. Non-inferiority criteria were defined as a lower boundary of the geometric mean ratio (GMR) being greater than 0.67. From September to October 2021, 118 adolescents with a median age (IQR) of 14.9 years (13.9–16.7) were enrolled. Fourteen days after the primary series, the geometric means (GMs) of anti-S-RBD IgG (BAU/mL) were 3090 (95% CI 2761–3460) in 3wPZ30/30. The GMRs of anti-S-RBD were: 0.80 (95% CI 0.67–0.97) in 3wPZ30/20; 1.00 (95% CI 0.83–1.20) in 3wPZ20/20; 1.37 (95% CI 1.13–1.65) in 6wPZ30/30; 1.24 (95% CI 1.02–1.50) in 6wPZ30/20; and 1.36 (1.13–1.64) in 6wPZ20/20. After a booster dose with 15 μg (n = 24) of BNT162b2, sVNT and pVNT against Omicron variant were 91.6 (95% CI 88.4–94.9) and 331 (95% CI 221–495), respectively. In the group that received 10 μg of BNT162b2 (n = 25), sVNT was 85.6 (95% CI 80.0–91.6) and pVNT was 397 (95% CI 267–590). Healthy adolescents had good immune responses to the fractional dose regimen of BNT162b2 and this may be considered as an alternative option.

Safety and Immunogenicity of an Inactivated COVID-19 Vaccine, WIBP-CorV, in Healthy Children: Interim Analysis of a Randomized, Double-Blind, Controlled, Phase 1/2 Trial

Safe and effective vaccines against SARS-CoV-2 for children are urgently needed. Here we aimed to assess the safety and immunogenicity of an inactivated COVID-19 vaccine candidate, WIBP-CorV, in participants aged 3-17 years. A randomized, double-blind, placebo-controlled, phase 1/2 clinical trial was conducted in Henan Province, China, in healthy children aged 3-17 years. 240 participants in phase 1 trial and 576 participants in phase 2 trial were randomly assigned to vaccine or control with an age de-escalation in three cohorts (3-5, 6-12 and 13-17 years) and dose-escalation in three groups (2.5, 5.0 and 10.0μg/dose), and received 3 intramuscular injections at day 0, 28, and 56. WIBP-CorV showed a promising safety profile with approximately 17% adverse reactions within 30 days after injection and no grade 3 or worse adverse events. The most common adverse reaction was injection site pain, followed by fever, which were mild and self-limiting. The geometric mean titers of neutralizing antibody ranged from 102.2 to 1065.5 in vaccinated participants at 28 days after the third vaccination, and maintained at a range of 14.3 to 218.2 at day 180 after the third vaccination. WIBP-CorV elicited significantly higher titers of neutralizing antibody in the cohort aged 3-5 years than the other two cohorts. There were no detectable antibody responses in all alum-only groups. Taken together, our data demonstrate that WIBP-CorV is safe and well tolerated at all tested doses in participants aged 3-17 years, and elicited robust humoral responses against SARS-CoV-2 lasted for at least 6 months after the third vaccination. This study is ongoing and is registered with www.chictr.org.cn, ChiCTR2000031809.

COVID-19 in children: epidemic issues and candidate vaccines

ABSTRACT

A large-scale vaccination of coronavirus disease-19 (COVID-19) in adults has been conducted for nearly a year, and there is a growing recognition that immunization for children is also essential. It has been months since emergency use of pediatric COVID-19 vaccine was approved, we reviewed the prevalence and transmission of COVID-19 in children. The prevalence of COVID-19 in children is reduced due to vaccination even in a Delta prevalent period, so an increase in the vaccination rate is needed in children. Although the precise role of children in the transmission requires more research to uncover, they likely played a significant role, according to the available literature. We also described four candidate COVID-19 vaccines for children on their safety and immunogenicity and the impact of severe acute respiratory syndrome coronavirus 2 variants on childhood vaccination. Safety issues on pediatric vaccines post-approval, like adverse events following immunization and adverse events of special interest require studies on long-term and effective regulatory mechanisms.

Parental Willingness to Vaccinate Their Children Against SARS-CoV-2 in Jordan: An Explanatory Cross-Sectional Study

Background

Successful control of the COVID-19 pandemic is largely dependent on vaccine administration to epidemiologically influential groups, including children. Considering that pediatric population comprises a significant portion on the population in developing countries, and their risk of infection and spreading the disease has been underestimated, it is crucial to investigate parental willingness to administer SARS-CoV-2 vaccine to their children between 5 and 11 years old. This study investigates the prevalence and determinants of parental willingness towards vaccinating their children (5–12 years old) against COVID-19 in a developing country setting, Jordan.

Methods

A cross-sectional study, conducted between October and November 2021, utilized online Google Forms to collect data on parents’ background characteristics, willingness to vaccinate their children, SARS-CoV-2, infection and vaccine, risk perception, and factors affecting decision to vaccinate.

Results

A total of 564 parents completed the questionnaire; 82.8% were mothers, 85.3% were 30 years of age or older, and 75.9% had bachelor’s degrees or higher. Only 25.4% of parents reported willingness to vaccinate their 5–12 years old children against SARS-CoV-2. Lower parental age, higher income, and having health insurance coverage increased parental willingness. Among participants vaccinated against COVID-19, only 29.0% were willing to vaccinate their children. Healthcare providers’ trust and vaccine recommendations by pediatricians increased parental willingness. COVID-19 risk perception seems to have negative effects on parental willingness.

Conclusion

A significant proportion of parents in Jordan indicated hesitancy towards administering COVID-19 vaccine for their children. Concerns about vaccine safety and trust in the healthcare system appear to be the most important predictors of parents’ hesitancy. Effective vaccine campaigns should focus on risk perception and communication and should consider parental socio-demographic characteristics.

Providing children with COVID-19 vaccinations is challenging due to lack of data and wide-ranging parental acceptance

AIM

Vaccines are vital to ending the COVID-19 pandemic and we reviewed the data on vaccinating children, and including them in clinical trials, as most of the activity has focused on adults.

METHODS

English and Chinese databases, including PubMed, Elsevier Scopus, Web of Science, CNKI and CQVIP were searched, along with websites such as the World Health Organization and the University of Oxford.

RESULTS

We identified 44 papers and 16 news items about vaccinating children against the virus, published from 10 February 2020 to 14 July 2021. Child vaccination has been slow and only a few countries have included children in Phase II or III clinical trials. The data on children were much more limited than on adults, but most children were asymptomatic or had mild symptoms and some deaths had been recorded. More clinical trials are needed to assess the safety and efficacy of vaccinating children, as higher vaccination levels can help to build up herd immunity. The percentage of parents willing to vaccinate their children against the virus ranged from 48.2% to 72.6%, with much lower rates for letting them participate in clinical trials.

CONCLUSION

Vaccines should be offered to children as soon as their safety and efficacy are established.

Safety & effectiveness of COVID-19 vaccines: A narrative review

There are currently eight vaccines against SARS-CoV-2 that have received Emergency Use Authorization by the WHO that can offer some protection to the world's population during the COVID-19 pandemic. Though research is being published all over the world, public health officials, policymakers and governments are collecting evidence-based information to establish the public health policies. Unfortunately, continued international travel, violations of lockdowns and social distancing, the lack of mask use, the emergence of mutant strains of the virus and lower adherence by a sector of the global population that remains sceptical of the protection offered by vaccines, or about any risks associated with vaccines, hamper these efforts. Here we examine the literature on the efficacy, effectiveness and safety of COVID-19 vaccines, with an emphasis on select categories of individuals and against new SARS-CoV-2 strains. The literature shows that these eight vaccines are highly effective in protecting the population from severe disease and death, but there are some issues concerning safety and adverse effects. Further, booster shots and variant-specific vaccines would also be required.

Safety and immunogenicity of an inactivated SARS-CoV-2 vaccine (CoronaVac) in inadvertently vaccinated healthy children

Twenty-seven children aged seven months to 5 years were inadvertently vaccinated with a COVID-19 vaccine, the CoronaVac (Sinovac, China), an inactivated SARS-CoV-2 vaccine, in two different cities of Sao Paulo State, Brazil. After the event, these children were monitored by local pediatricians and serum samples were collected at the first visit and 30 days after vaccination and tested for SARS-CoV-2 S1 serology with Ortho total IgG anti-S1 protein and Cpass, an ACE2 receptor binding domain inhibition assay. Only one child had a mild symptom after vaccination, with no other adverse events documented up to the 30 days follow-up. Of 27 children tested 3-9 days after vaccination, 5 (19%) had positive serology suggesting a previous natural SARS-CoV-2 infection, with all 19 tested on day 30 after vaccination and presenting with positive tests, with an increment of antibody titers in those initially positive. A low Cpass binding inhibition was observed in the first collection in 11 seronegative cases, with high titers among those anti-S1 positive. All children showed an important increase in antibody titers on day 30. The event allowed the documentation of a robust serological response to one dose of CoronaVac in this small population of young children, with no major adverse effects. Although it was an unfortunate accident, this event may contribute with future vaccine strategies in this age group. The data suggest that CoronaVac is safe and immunogenic for children.

Parental plans to vaccinate children for COVID-19 in New York city

Once COVID-19 vaccines are approved for children < 12 years of age, high pediatric vaccination coverage will be needed to help minimize the public health threat from the SARS-CoV-2 epidemic. We conducted an online survey of 1,119 parents and caregivers of children ≤ 12 years in New York City from March 9 to April 11, 2021. Among parents surveyed, 61.9% reported plans to vaccinate their youngest child for COVID-19, 14.8% said they do not plan to vaccinate their child and 23.3% were unsure. Female and non-Hispanic Black parents were least likely to report plans to vaccinate their children. Safety, effectiveness and perceptions that children do not need vaccination were the primary reasons for vaccine hesitancy/resistance. Parents who have or will vaccinate themselves were significantly more likely to report they would vaccinate their children. Efforts to increase awareness about vaccine safety and education about the importance of vaccinating children are needed.

Safety, Immunogenicity, and Efficacy of the BNT162b2 Covid-19 Vaccine in Adolescents

BACKGROUND

Until very recently, vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) had not been authorized for emergency use in persons younger than 16 years of age. Safe, effective vaccines are needed to protect this population, facilitate in-person learning and socialization, and contribute to herd immunity.

METHODS

In this ongoing multinational, placebo-controlled, observer-blinded trial, we randomly assigned participants in a 1:1 ratio to receive two injections, 21 days apart, of 30 μg of BNT162b2 or placebo. Noninferiority of the immune response to BNT162b2 in 12-to-15-year-old participants as compared with that in 16-to-25-year-old participants was an immunogenicity objective. Safety (reactogenicity and adverse events) and efficacy against confirmed coronavirus disease 2019 (Covid-19; onset, ≥7 days after dose 2) in the 12-to-15-year-old cohort were assessed.

RESULTS

Overall, 2260 adolescents 12 to 15 years of age received injections; 1131 received BNT162b2, and 1129 received placebo. As has been found in other age groups, BNT162b2 had a favorable safety and side-effect profile, with mainly transient mild-to-moderate reactogenicity (predominantly injection-site pain [in 79 to 86% of participants], fatigue [in 60 to 66%], and headache [in 55 to 65%]); there were no vaccine-related serious adverse events and few overall severe adverse events. The geometric mean ratio of SARS-CoV-2 50% neutralizing titers after dose 2 in 12-to-15-year-old participants relative to 16-to-25-year-old participants was 1.76 (95% confidence interval [CI], 1.47 to 2.10), which met the noninferiority criterion of a lower boundary of the two-sided 95% confidence interval greater than 0.67 and indicated a greater response in the 12-to-15-year-old cohort. Among participants without evidence of previous SARS-CoV-2 infection, no Covid-19 cases with an onset of 7 or more days after dose 2 were noted among BNT162b2 recipients, and 16 cases occurred among placebo recipients. The observed vaccine efficacy was 100% (95% CI, 75.3 to 100).

CONCLUSIONS

The BNT162b2 vaccine in 12-to-15-year-old recipients had a favorable safety profile, produced a greater immune response than in young adults, and was highly effective against Covid-19. (Funded by BioNTech and Pfizer; C4591001 ClinicalTrials.gov number, NCT04368728.).

Recommendations for acceleration of vaccine development and emergency use filings for COVID-19 leveraging lessons from the novel oral polio vaccine

A new oral polio vaccine, nOPV2, has become the first vaccine to pursue a WHO Emergency Use Listing. Many lessons were learned as part of the accelerated development plan and submission, which have been categorized under the following sections: regulatory, clinical development, chemistry manufacturing and controls, and post-deployment monitoring. Efforts were made to adapt findings from these studies to COVID-19 vaccine candidates. Specific concepts for accelerating COVID-19 vaccine development across multiple functional domains were also included. The goals of this effort were twofold: (1) to help familiarize vaccine developers with the EUL process; and (2) to provide general guidance for faster development and preparations for launch during the COVID-19 pandemic.

Why It Is Important to Develop an Effective and Safe Pediatric COVID-19 Vaccine

The need to cope with the medical, social, and economic storm due to the new coronavirus 2019 (COVID-19) pandemic as quickly as possible has led to the very rapid development of a huge number of vaccines. All these vaccines have been mainly developed in healthy adults and, in some cases, in the elderly. Children were marginally involved as, according to the clinical trial registry Clinical Trials.gov, only very few studies have included children among subjects to enroll, although just a few weeks after the pandemic declaration, the US Food and Drug Administration had highlighted the importance of vaccine evaluation in pediatrics. Availability of an effective and safe pediatric COVID-19 vaccine appears mandatory for several clinical and epidemiological reasons. However, as the development of an effective and safe pediatric vaccine seems far from easy, strong cooperation among governments, researchers, and pharmaceutical companies is highly desirable.

Influenza vs. COVID-19: Comparison of Clinical Characteristics and Outcomes in Pediatric Patients in Mexico City

Introduction: Respiratory viruses are among the leading causes of disease and death among children. Co-circulation of influenza and SARS-CoV2 can lead to diagnostic and management difficulties given the similarities in the clinical picture. Methods: This is a cohort of all children hospitalized with SARS-CoV2 infection from March to September 3rd 2020, and all children admitted with influenza throughout five flu-seasons (2013-2018) at a pediatric referral hospital. Patients with influenza were identified from the clinical laboratory database. All hospitalized patients with confirmed SARS-CoV2 infection were followed-up prospectively. Results: A total of 295 patients with influenza and 133 with SARS-CoV2 infection were included. The median age was 3.7 years for influenza and 5.3 years for SARS-CoV2. Comorbidities were frequent in both groups, but they were more common in patients with influenza (96.6 vs. 82.7%, p < 0.001). Fever and cough were the most common clinical manifestations in both groups. Rhinorrhea was present in more than half of children with influenza but was infrequent in those with COVID-19 (53.6 vs. 5.8%, p < 0.001). Overall, 6.4% percent of patients with influenza and 7.5% percent of patients with SARS-CoV2 infection died. In-hospital mortality and the need for mechanical ventilation among symptomatic patients were similar between groups in the multivariate analysis. Conclusions: Influenza and COVID-19 have a similar picture in pediatric patients, which makes diagnostic testing necessary for adequate diagnosis and management. Even though most cases of COVID-19 in children are asymptomatic or mild, the risk of death among hospitalized patients with comorbidities may be substantial, especially among infants.

Asymptomatic SARS Coronavirus 2 infection: Invisible yet invincible

While successful containment measures of COVID-19 in China and many European countries have led to flattened curves, case numbers are rising dramatically in other countries, with the emergence of a second wave expected. Asymptomatic individuals carrying SARS-CoV-2 are hidden drivers of the pandemic, and infectivity studies confirm the existence of transmission by asymptomatic individuals. The data addressed here show that characteristics of asymptomatic and presymptomatic infection are not identical. Younger age correlates strongly with asymptomatic and mild infections and children as hidden drivers. The estimated proportion of asymptomatic infections ranges from 18% to 81%. The current perception of asymptomatic infections does not provide clear guidance for public-health measures. Asymptomatic infections will be a key contributor in the spread of COVID-19. Asymptomatic cases should be reported in official COVID-19 statistics.