Summary Background School closures have occurred globally during the COVID-19 pandemic. However, empiric data on transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) among children and in educational settings are scarce. In Australia, most schools have remained open during the first epidemic wave, albeit with reduced student physical attendance at the epidemic peak. We examined SARS-CoV-2 transmission among children and staff in schools and early childhood education and care (ECEC) settings in the Australian state of New South Wales (NSW). Methods Laboratory-confirmed paediatric (aged ≤18 years) and adult COVID-19 cases who attended a school or ECEC setting while considered infectious (defined as 24 h before symptom onset based on national guidelines during the study period) in NSW from Jan 25 to April 10, 2020, were investigated for onward transmission. All identified school and ECEC settings close contacts were required to home quarantine for 14 days, and were monitored and offered SARS-CoV-2 nucleic acid testing if symptomatic. Enhanced investigations in selected educational settings included nucleic acid testing and SARS-CoV-2 antibody testing in symptomatic and asymptomatic contacts. Secondary attack rates were calculated and compared with state-wide COVID-19 rates. Findings 15 schools and ten ECEC settings had children (n=12) or adults (n=15) attend while infectious, with 1448 contacts monitored. Of these, 633 (43·7%) of 1448 had nucleic acid testing, or antibody testing, or both, with 18 secondary cases identified (attack rate 1·2%). Five secondary cases (three children; two adults) were identified (attack rate 0·5%; 5/914) in three schools. No secondary transmission occurred in nine of ten ECEC settings among 497 contacts. However, one outbreak in an ECEC setting involved transmission to six adults and seven children (attack rate 35·1%; 13/37). Across all settings, five (28·0%) of 18 secondary infections were asymptomatic (three infants [all aged 1 year], one adolescent [age 15 years], and one adult). Interpretation SARS-CoV-2 transmission rates were low in NSW educational settings during the first COVID-19 epidemic wave, consistent with mild infrequent disease in the 1·8 million child population. With effective case-contact testing and epidemic management strategies and associated small numbers of attendances while infected, children and teachers did not contribute significantly to COVID-19 transmission via attendance in educational settings. These findings could be used to inform modelling and public health policy regarding school closures during the COVID-19 pandemic. Funding NSW Government Department of Health.

ObjectiveTo actively solicit adverse events experienced in the days following immunisation with quadrivalent inactivated influenza vaccine using Australia’s near real-time, participant-based vaccine safety surveillance system, AusVaxSafety.Design and settingObservational cohort study conducted in 194 sentinel surveillance immunisation sites (primary care, hospital and community-based clinics) across Australia.ParticipantsIndividuals aged ≥6 months who received a routine seasonal influenza vaccine at a participating site (n=102 911) and responded to a survey (via short message service or email) sent 3 days after vaccination about adverse events experienced (n=73 892; 71.8%).Main outcome measureNear real-time and cumulative participant-reported rates of any adverse event, fever or medical attendance experienced within 3 days after vaccination overall, by brand, age, pregnancy status and concomitant vaccine receipt.ResultsParticipant median age was 57 years (range: 6 months to 102 years); 58.1% (n=42 869) were female and 2.7% (n=2018) were pregnant. Near real-time fast initial response cumulative summation and Bayesian analyses of weekly event rates did not demonstrate a safety signal. Children aged 6 months to 4 years had higher event rates (522/6180; 8.4%) compared with older ages; participants aged ≥65 years reported fewer events (1695/28 154; 6.0%). There were no clinically significant differences in safety between brands, by age group or overall. Cumulative data analysis demonstrated that concomitant vaccination was associated with increased rates of fever (2.1% vs 0.8%) and medical attendance (0.8% vs 0.4%), although all rates were low and did not exceed expected levels.ConclusionsNovel, postmarketing AusVaxSafety surveillance demonstrated comparable and expected safety outcomes for the 2017 quadrivalent inactivated influenza vaccine brands used in Australia. These near real-time, participant-reported data are expected to encourage confidence in vaccine safety and promote uptake.

Objectives: To describe the severity and clinical spectrum of coronavirus disease 2019 (COVID‐19) in children during the 2021 New South Wales outbreak of the Delta variant of the severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2). Design, setting: Prospective cohort study in three metropolitan Sydney local health districts, 1 June – 31 October 2021. Participants: Children under 16 years of age with positive SARS‐CoV‐2 nucleic acid test results admitted to hospital or managed by the Sydney Children’s Hospital Network (SCHN) virtual care team. Main outcome measures: Age‐specific SARS‐CoV‐2 infection frequency, overall and separately for SCHN virtual and hospital patients; rates of medical and social reason admissions, intensive care admissions, and paediatric inflammatory multisystem syndrome temporally associated with SARS‐CoV‐2 per 100 SARS‐CoV‐2 infections; demographic and clinical factors that influenced likelihood of hospital admission. Results: A total of 17 474 SARS‐CoV‐2 infections in children under 16 were recorded in NSW, of whom 11 985 (68.6%) received SCHN‐coordinated care, including 459 admitted to SCHN hospitals: 165 for medical reasons (1.38 [95% CI, 1.17–1.59] per 100 infections), including 15 admitted to intensive care, and 294 (under 18 years of age) for social reasons (2.45 [95% CI, 2.18–2.73] per 100 infections). In an analysis that included all children admitted to hospital and a random sample of those managed by the virtual team, having another medical condition (adjusted odds ratio [aOR], 7.42; 95% CI, 3.08–19.3) was associated with increased likelihood of medical admission; in univariate analyses, non‐asthmatic chronic respiratory disease was associated with greater (OR, 9.21; 95% CI, 1.61–174) and asthma/viral induced wheeze with lower likelihood of admission (OR, 0.38; 95% CI, 0.18–0.78). The likelihood of admission for medical reasons declined from infancy to 5–11 years, but rose again for those aged 12–15 years. Sex and Indigenous status did not influence the likelihood of admission. Conclusion: Most SARS‐CoV‐2 infections (Delta variant) in children were asymptomatic or associated with mild disease. Hospitalisation was relatively infrequent, and most common for infants, adolescents, and children with other medical conditions. More children were hospitalised for social than for medical reasons.