Presence of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Antibodies Among Vietnamese Healthcare Workers by Dosing Interval for ChAdOx1 nCoV-19 Vaccine.

BACKGROUND: Before the SARS-CoV-2 Delta variant arrived in Vietnam, case rates suggested seroprevalence of SARS-CoV-2 was low. Beginning in March 2021, we assessed different dosing schedules and adverse events following immunization (AEFIs) for ChAdOx1 nCoV-19 vaccine among healthcare workers (HCWs). METHODS: We performed a prospective cohort study to estimate the prevalence of IgG antibodies to SARS-CoV-2 before and after ChAdOx1 nCoV-19 vaccination. We conducted antibody testing among HCWs in February 2021 (baseline), before the second dose (June-July 2021), and 1 and 3 months after the second dose. We detected antibodies to SARS-CoV-2 using Tetracore® FlexImmArray™, and surrogate neutralizing antibodies using GenScript cPass™. Neither assay can distinguish natural from vaccine-induced antibodies. We assessed AEFIs through interview post-dose 1 and 1 month post-dose 2. RESULTS: Before vaccination, 1/617 participants (0.16%) had antibodies to SARS-CoV-2. Of these 617, 405 were vaccinated with ChAdOx1 nCoV-19 with 4-8- (60%), 9-12- (27%), or ≥13-week (13%) intervals between the 2 doses. Three months following series completion, 99% and 97% of vaccinated participants had ≥1 sample with detectable antibodies and surrogate neutralizing antibodies against SARS-CoV-2, respectively. We observed no significant differences among those with different dosing intervals at last follow-up. All participants reported PCR testing for SARS-CoV-2 during the study; 2 (0.5%) were laboratory-confirmed. AEFIs were more frequent post-dose 1 (81%) vs post-dose 2 (21%). CONCLUSIONS: In this population, regardless of dosing interval, ChAdOx1 nCoV-19 induced antibodies within 3 months of the second dose. These findings may offer flexibility to policymakers when balancing programmatic considerations with vaccine effectiveness.

Feasibility and Acceptability of Technology-supported Sexual Health Education Among Adolescents Receiving Inpatient Psychiatric Care.

Mental illness in adolescence is associated with high-risk sexual behaviors including multiple sex partners, infrequent or inconsistent condom use, and nonuse of contraception. Inpatient psychiatric care represents a promising setting to provide sexual health education. This pilot study investigates the feasibility and acceptability of online sexual health education in this group by assessing usability and impact on short-term psychosocial outcomes. We administered online modules on healthy relationships, pregnancy prevention, condom use, and sexually transmitted infection (STI) prevention to youth. We evaluated outcomes using a single group, pre/post-intervention design. One quality improvement session assessed staff acceptability of the programming. Participants included 51 inpatients (mean age = 15.3; 61% female; 57% Hispanic or Latino; 55% heterosexual). Overall, the program was feasible to administer and highly acceptable to youth (84-89% liked the modules, 98-100% found them easy to use, 96-100% found them credible, 91-98% said information would lead to healthier dating relationships, and 78-87% would refer to a friend). Youth who completed modules demonstrated improvement in several outcomes: attitudes and norms towards violence (p < 0.001), intention to use a method of birth control other than condoms if having sex in the next 3 months (p < 0.001), condom knowledge (p < 0.001), condom use self-efficacy (p < 0.001), condom beliefs (p = 0.04), HIV/STI knowledge (p < 0.001), and perceived susceptibility to STI (p < 0.01). The quality improvement session revealed high acceptability by nursing staff on the unit. This intervention could be useful and efficacious in an inpatient setting and larger studies are warranted to understand its full impact.