ABSTRACT
Coronavirus disease 2019 affected child health and impacted learning because of the resulting onsite school closures. This prospective cohort study included children aged 10-17 who received two 4 µg doses of BBIBP-CorV administered intramuscularly 21-28 days apart. To assess vaccine safety, 36,808 participants were then followed with paper- and web-based online questionnaire surveys that captured local and systemic reactogenicities following vaccine administration on days 1, 7, and 30. Among participants, 76% (27,880) reported reactogenicity within the first 24 h and 7 days following the first dose. Half (51.41%) of participants experienced pain at the injection site; the majority of cases were mild in severity. Injection site tenderness (37.93%) was another common local reaction. Fatigue (37.89%), myalgia (33.56%), and headache (26.76%) were the most common systemic reactions. On days 2-7 after the first dose, 25.85% of participants experienced adverse reactions. Following the second dose, reactogenicity was 7.6% and 1.09% within 24 h and between days 2-7. The majority of reactions were of mild to moderate severity. We report that two doses of the BBIBP-CorV caused mild to moderate side effects in adolescents in Thailand. The findings confirm the vaccine's safety profile in this age group.
ABSTRACT
Objectives: Patients with cancer may be at an increased risk of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and experience more severe outcomes. Low vaccine coverage in the early phase of the coronavirus disease 2019 (COVID-19) pandemic meant that personal and social measures to reduce viral spread were the only methods of lowering the risk of infection among cancer patients. This study explored the prevalence of SARS-CoV-2 antibodies in cancer patients and caregivers in a cancer hospital after the second COVID-19 outbreak in Thailand. Study design: Cross-sectional study. Methods: A SARS-CoV-2 seroprevalence cross-sectional survey was conducted among 200 cancer patients and 200 household caregivers in a tertiary cancer care hospital in Bangkok, Thailand. The survey took place between 4 March and May 31, 2021 - a time period covering the end of the second COVID-19 wave and the early phase of the third wave in Thailand. Results: Rigorous personal and social measures to reduce viral spread among cancer patients and caregivers lead to an extremely low prevalence of SARS-CoV2 infection (0% among cancer patients and 1% among household caregivers). Conclusion: This study demonstrates the importance of social distancing and personal hygiene measures for the prevention of SARS-CoV-2 infection, even when vaccine coverage is low.
ABSTRACT
Adolescents can develop a severe form of Coronavirus disease 2019 (COVID-19), especially with underlying comorbidities. No study has examined the efficacy or effectiveness of inactivated COVID-19 vaccines in adolescents. This single-center, prospective cohort study was performed to evaluate the safety and effectiveness of an inactivated COVID-19 vaccine in adolescents using the immunobridging approach at Chulabhorn Hospital. The key eligibility criterion was a healthy clinical condition or stable pre-existing comorbidity. The anti-receptor-binding domain (anti-RBD) antibody concentration at 4 weeks after dose 2 of the vaccine was compared between participants aged 12 to 17 years and those aged 18 to 30 years. Safety profiles included adverse events within 7 days after each dose of the vaccine and any adverse events through 1 month after dose 2 of the vaccine. In the adolescent and adult cohorts, the geometric mean concentration of anti-RBD antibody was 102.9 binding antibody unit (BAU)/mL (95% CI, 91.0-116.4) and 36.9 BAU/mL (95% CI, 30.9-44.0), respectively. The geometric mean ratio of the adolescent cohort was 2.79 (95% CI, 2.25-3.46, p < 0.0001) compared with the adult cohort, meeting the non-inferiority criterion. The reactogenicity was slightly lower in the adolescent than in the adult cohort. No serious adverse events occurred. The inactivated COVID-19 vaccine appears safe and effective in adolescents.