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1.
researchsquare; 2022.
Preprint in English | PREPRINT-RESEARCHSQUARE | ID: ppzbmed-10.21203.rs.3.rs-1646307.v1

ABSTRACT

Background: In England, the emergence the more transmissible SARS-CoV-2 variant Alpha (B.1.1.7) led to a third national lockdown from December 2020, including restricted attendance at schools. Nurseries, however, remained fully open. COVID-19 outbreaks (≥ 2 laboratory-confirmed cases within 14 days) in nurseries and assess the risk of SARS-CoV-2 infection and incidence rates in staff and children over a three-month period when community SARS-CoV-2 infections rates were high and the Alpha variant was spreading rapidly across England. Methods This was a cross-sectional national investigation of COVID-19 outbreaks in nurseries across England Nurseries reporting a COVID-19 outbreak to PHE between November 2020 and January 2021 were requested to complete a questionnaire about their outbreak. Results 324 nurseries, comprising 1% (324/32,852) of nurseries in England, reported a COVID-19 outbreak. Of the 315 (97%) nurseries contacted, 173 (55%) reported 1,657 SARS-CoV-2 cases, including 510 (31%) children and 1,147 (69%) staff. A child was the index case in 45 outbreaks (26%) and staff in 125 (72%) outbreaks. Overall, children had an incidence rate of 3.50% (95%CI, 3.21–3.81%) and was similar irrespective of whether the index case was a child (3.55%; 95%CI, 3.01–4.19%) or staff (3.44%; 95%CI, 3.10–3.82%). Among staff, incidence rates were lower if the index case was a child (26.28%; 95%CI, 23.54–29.21%%) compared to a staff member (32.98%; 95%CI, 31.19–34.82%), with the highest incidence rate when the index case was also a staff member (37.52%; 95%CI, 35.39–39.70%). Compared to November 2020, outbreak sizes and incidence rates were higher in January 2021, when the Alpha variant predominated. Nationally, SARS-CoV-2 infection rates in


Subject(s)
COVID-19
2.
medrxiv; 2021.
Preprint in English | medRxiv | ID: ppzbmed-10.1101.2021.12.10.21267408

ABSTRACT

Adolescents in the UK were recommended to have their first dose of mRNA vaccine during a period of high community transmission due to the highly transmissible Delta variant, followed by a second dose at an extended interval of 8-12 weeks. We used national SARS-CoV-2 testing, vaccination and hospitalisation data to estimate vaccine effectiveness (VE) using a test-negative case-control design, against PCR-confirmed symptomatic COVID-19 in England. VE against symptomatic disease increased to 80% within two weeks of the first dose of BNT162b2 vaccine (higher than in adults aged 18-64 years) and then declines rapidly to 40% within 8 weeks (similar to adults). Early data in 16-17-year-olds also indicate high protection against hospitalisation and a rapid increase in VE against symptomatic COVID-19 after the second dose. Our data highlight the importance of the second vaccine dose for protection against symptomatic COVID-19 and raise important questions about the objectives of an adolescent immunisation programme. If prevention of infection is the primary aim, then regular COVID-19 vaccine boosters will be required.


Subject(s)
COVID-19
3.
medrxiv; 2021.
Preprint in English | medRxiv | ID: ppzbmed-10.1101.2021.04.12.21255275

ABSTRACT

SARS-CoV-2 infection is generally mild or asymptomatic in children but the biological basis for this is unclear. We studied the profile of antibody and cellular immunity in children aged 3-11 years in comparison with adults. Antibody profiles in children were strong with high titres against spike protein and receptor binding domain (RBD). SARS-CoV-2 seroconversion in children strongly boosted antibody responses against seasonal beta-coronaviruses, partly through cross-recognition of the S2 domain, indicating a broad humoral response that was not seen in adults. T cell responses against spike were also >2-fold higher in children compared to adults and displayed a strong Th1 cytokine profile. SARS-CoV-2 spike-reactive cellular responses were present in more than half the seronegative children, indicating pre-existing cross-reactive responses or sensitization against SARS-CoV-2. Importantly, all children retained high antibody titres and cellular responses for more than 6 months after infection whilst relative antibody waning was seen in adults. Children thus distinctly generate robust, cross-reactive and sustained immune responses after SARS-CoV-2 infection with focussed specificity against spike protein. These observations demonstrate several novel features of SARS-CoV-2-specific immune responses in children and may provide insights into relative clinical protection in this group. Such information on the profile of natural infection will help to guide the introduction of vaccination regimens into the paediatric population.


Subject(s)
COVID-19
4.
ssrn; 2021.
Preprint in English | PREPRINT-SSRN | ID: ppzbmed-10.2139.ssrn.3826200

ABSTRACT

Background: The reopening of schools during the COVID-19 pandemic has raised concerns about widespread infection and transmission of SARS-CoV-2 in educational settings. In June 2020, Public Health England (PHE) initiated prospective national surveillance of SARS-CoV-2 in primary schools across England (sKIDs). We used this opportunity to assess the feasibility and agreeability of large-scale surveillance and testing for SARS-CoV-2 infections in school among staff, parents and students.Methods: Staff and students in 131 primary schools were asked to complete a questionnaire at recruitment and provide weekly nasal swabs for SARS-CoV-2 RT-PCR testing (n=86) or swabs with blood samples for antibody testing (n=45) at the beginning and end the summer half-term. In six blood sampling schools, students were asked to complete a pictorial questionnaire before and after their investigations.Results: In total, 134 children aged 4-7 years (n=40) or 8-11 years (n=95) completed the pictorial questionnaire fully or partially. Prior to sampling, oral fluid sampling was the most acceptable test (107/132, 81%) followed by throat swabs (80/134, 59%), nose swabs (77/132, 58%), and blood tests (48/130, 37%). Younger students were more nervous about all tests than older students but, after completing their tests, most children reported a “better than expected” experience with all the investigations. Students were more likely to agree to additional testing for nose swabs (93/113, 82%) and oral fluid (93/114, 82%), followed by throat swabs (85/113, 75%) and blood tests (72/108, 67%). Parents (n=3,994) and staff (n=2,580) selected a preference for weekly testing with nose swabs, throat swabs or oral fluid sampling, although staff were more flexible about testing frequency. Conclusions: Primary school staff and parents were supportive of regular tests for SARS-CoV-2 and selected a preference for weekly testing. Children preferred nose swabs and oral fluids over throat swabs or blood sampling.Funding Statement: This surveillance was internally funded by PHE and did not receive any specific grant funding from agencies in the public, commercial or not-for-profit sectors.Declaration of Interests: None.Ethics Approval Statement: PHE has legal permission, provided by Regulation 3 of The Health Service (Control of Patient Information) Regulations 2002, to process patient confidential information for national surveillance of communicable diseases and as such, individual patient consent is not required.


Subject(s)
COVID-19
5.
ssrn; 2021.
Preprint in English | PREPRINT-SSRN | ID: ppzbmed-10.2139.ssrn.3766014

ABSTRACT

Background: The full reopening of schools in September 2020 was associated with an increase in COVID-19 cases and outbreaks in educational settings across England. Methods: Primary and secondary schools reporting an outbreak (≥2 laboratory-confirmed cases within 14 days) to Public Health England (PHE) between 31 August and 18 October 2020 were contacted to complete an online questionnaire. Interpretation: There were 969 primary (n=450) and secondary school outbreaks (n=519) reported to PHE, representing 3% of primary schools and 15% of secondary schools in England. Of the 369 schools contacted, 190 geographically-representative schools completed the questionnaire; 2,425 cases were reported. Secondary school students (1.20%; 95%CI, 1.13-1.28%) had higher attack rates than primary school students (0.84%; 95%CI, 0.75-0.94%). Outbreaks were larger and across more year groups in secondary schools than in primary schools. When an outbreak occurred, attack rates were higher in staff (926/19,083; 4.85%; 95%CI, 4.55-5.17%) than students, especially among primary school teaching staff (9.81%; 95%CI, 8.90-10.82%) compared to secondary school teaching staff (3.97%; 95%CI, 3.79-5.69%). Staff represented 59% (471/799) of cases in primary school outbreaks and 27% (410/1515) in secondary schools (P<0.001). Teaching staff were more likely to be the index case in primary (48/100, 48%) than in secondary (25/79, 32%) schools (P=0.027).Conclusions: Secondary schools were more likely to be affected by a COVID-19 outbreak than primary schools and to experience larger outbreaks across multiple school years. The higher attack rate among teaching staff during an outbreak suggests that additional protective measures may be needed. Funding: PHE


Subject(s)
COVID-19
6.
ssrn; 2021.
Preprint in English | PREPRINT-SSRN | ID: ppzbmed-10.2139.ssrn.3766774

ABSTRACT

Background: Many countries re-opened schools after national lockdown but little is known about the risk of SARS-CoV-2 infection and transmission in educational settings. Public Health England conducted six-month prospective surveillance in primary schools across England. Methods: The COVID-19 Surveillance in School KIDs (sKIDs) study included two arms: weekly nasal swabs for ≥4 weeks following partial reopening during the summer half-term (June to mid-July 2020) and blood sampling with nasal and throat swabs at the beginning and end of the summer half-term, and, following full reopening in September 2020, at the end of the autumn term (end-November 2020). Results: In round 1, 12,026 participants (59.1% students, 40.9% staff) in 131 schools had 43,091 swabs taken. Weekly SARS-CoV-2 infection rates were 3.9 (1/25,537; 95% CI, 0.10-21.8) and 11.3 (2/17,554; 95% CI, 1.4-41.2) per 100,000 students and staff. At recruitment, N-antibody positivity in 45 schools was 11.1% (91/817; 95%CI, 9.2-13.5%) in students and 15.1% (209/1381; 95%CI, 13.3-17.1%) in staff, similar to local community seroprevalence. Seropositivity was not associated with school attendance during lockdown or staff contact with students. Round 2 participation was 73.7% (1,619/2,198) and only five (4 students, 1 staff) seroconverted. In round 3, when 61.9% (1,361/2,198) of round 1 participants were re-tested, seroconversion rates were 3.4% (19/562; 95%CI, 2.0-5.2) in students and 3.9% (36/930; 95%CI, 2.7-5.3) in staff. Conclusions: SARS-CoV-2 infection rates, assessed using nasal swabs for acute infection and serum antibodies for prior infection, were low following partial and full reopening of primary schools in England.Funding Statement: This surveillance was funded by the Department of Health and Social Care (DHSC).Declaration of Interests: None to declare.Ethics Approval Statement: The surveillance protocol was approved by the Public Health England Research Ethics Governance Group (R&D REGG Ref: NR0209, 16 May 2020).


Subject(s)
COVID-19
7.
ssrn; 2021.
Preprint in English | PREPRINT-SSRN | ID: ppzbmed-10.2139.ssrn.3761920

ABSTRACT

Background: The reopening of schools during the COVID-19 pandemic has raised concern for the safety of staff and students, their families and the wider community. We monitored SARS-CoV-2 infection rates in school-aged children and compared them with adult infection rates before and after schools reopened in England. Methods: Public Health England receives daily electronic reports of all SARS-CoV-2 tests nationally. SARS-CoV-2 infection rates by school year from July to November 2020 were analysed, including the effect of a week-long half-term school break in October and national month-long lockdown whilst keeping schools open in November 2020Findings: SARS-CoV-2 infections rates were low during early summer but started increasing in mid-August, initially in young adults followed by secondary and then primary school-aged children prior to schools reopening in September 2020. Cases in school-aged children lagged behind and followed adult trends after schools reopened, with a strong age gradient in weekly infection rates. There was a strong (P<0.001) correlation in regional infection rates between adults and secondary (R2=0.96-0.98), primary (R2=0.93-0.94) and preschool-aged (R2=0.62-0.85) children. The half-term break had a small and transient effect on infection rates in school-aged children, but there was a sharp decline in adult cases followed a week later by a decline in student cases after national lockdown in November 2020.Interpretation: In school-aged children, SARS-CoV-2 infections followed the same trajectory as adult cases and only declined after national lockdown was implemented whilst keeping schools open. Maintaining low community infection rates is critical for keeping schools open during the pandemic.Funding: PHE


Subject(s)
COVID-19
8.
ssrn; 2021.
Preprint in English | PREPRINT-SSRN | ID: ppzbmed-10.2139.ssrn.3761838

ABSTRACT

Background: The full reopening of schools in September 2020 was associated with an increase in COVID-19 cases and outbreaks in educational settings across England.Methods: Primary and secondary schools reporting an outbreak (≥2 laboratory-confirmed cases within 14 days) to Public Health England (PHE) between 31 August and 18 October 2020 were contacted to complete an online questionnaire.Interpretation: There were 969 primary (n=450) and secondary school outbreaks (n=519) reported to PHE, representing 3% of primary schools and 15% of secondary schools in England. Of the 369 schools contacted, 190 geographically-representative schools completed the questionnaire; 2,425 cases were reported. Secondary school students (1.20%; 95%CI, 1.13-1.28%) had higher attack rates than primary school students (0.84%; 95%CI, 0.75-0.94%). Outbreaks were larger and across more year groups in secondary schools than in primary schools. When an outbreak occurred, attack rates were higher in staff (926/19,083; 4.85%; 95%CI, 4.55-5.17%) than students, especially among primary school teaching staff (378/3852; 9.81%; 95%CI, 8.90-10.82%) compared to secondary school teaching staff (284/7146; 3.97%; 95%CI, 3.79-5.69%). Staff represented 59% (471/799) of cases in primary school outbreaks and 27% (410/1515) in secondary schools (P<0.001). Teaching staff were more likely to be the index case in primary (48/100, 48%) than in secondary (25/79, 32%) schools (P=0.027). Conclusions: Secondary schools were more likely to be affected by a COVID-19 outbreak than primary schools and to experience larger outbreaks across multiple school years. The higher attack rate among teaching staff during an outbreak suggests that additional protective measures may be needed.Funding Statement: This surveillance was internally funded by PHE and did not receive any specific grant funding from agencies in the public, commercial or not-for-profit sectors.Declaration of Interests: The authors declare no conflicts of interest.Ethics Approval Statement: PHE has legal permission, provided by Regulation 3 of The Health Service (Control of Patient Information) Regulations 2002, to process patient confidential information for national surveillance of communicable diseases and as such, individual patient consent is not required.


Subject(s)
COVID-19
9.
ssrn; 2020.
Preprint in English | PREPRINT-SSRN | ID: ppzbmed-10.2139.ssrn.3675431

ABSTRACT

Background: There are limited data on SARS-CoV-2 infection and transmission in educational settings. This information is critical for policy makers and practitioners to ensure the safety of staff, students and the wider community during the COVID-19 pandemic.Methods: Public Health England initiated enhanced national surveillance following the reopening of educational settings during the summer mini-term on 01 June 2020. COVID-19 related situations in educational settings across England were reviewed daily and followed-up until 31 July 2020. SARS-CoV-2 infection and outbreak rates were calculated for staff and students attending early year settings, primary and secondary schools during June 2020. Findings: There were 67 single confirmed cases, 4 co-primary cases and 30 COVID-19 outbreaks during June 2020, with a strong correlation between number of outbreaks and regional COVID-19 incidence (0.51 outbreaks for each SARS-CoV-2 infection per 100,000 in the community; p=0.001). Overall, SARS-CoV-2 infections and outbreaks were uncommon across all educational settings. Staff members had an increased risk of SARS-CoV-2 infections compared to students in any educational setting, and the majority of cases linked to outbreaks were in staff. The probable transmission direction for the 30 confirmed outbreaks was: staff-to-staff (n=15), staff-to-student (n=7), student-to-staff (n=6) and student-to-student (n=2).Interpretation: SARS-CoV2 infections and outbreaks were uncommon in educational settings during the first month after the easing of national lockdown in England. The strong correlation with regional SARS-CoV-2 incidence emphasises the importance of controlling community transmission to protect educational settings. Additional interventions should focus on reducing transmission in and among staff members.Funding: NoneDeclaration of Interests: The authors declare no conflicts of interest.Ethics Approval Statement: PHE has legal permission, provided by Regulation 3 of The Health Service (Control of Patient Information) Regulations 2002, to process patient confidential information for national surveillance of communicable diseases and as such, individual patient consent is not required.


Subject(s)
COVID-19
10.
medrxiv; 2020.
Preprint in English | medRxiv | ID: ppzbmed-10.1101.2020.08.21.20178574

ABSTRACT

BackgroundThere are limited data on SARS-CoV-2 infection and transmission in educational settings. This information is critical for policy makers and practitioners to ensure the safety of staff, students and the wider community during the COVID-19 pandemic. MethodsPublic Health England initiated enhanced national surveillance following the reopening of educational settings during the summer mini-term on 01 June 2020. COVID-19 related situations in educational settings across England were reviewed daily and followed-up until 31 July 2020. SARS-CoV-2 infection and outbreak rates were calculated for staff and students attending early year settings, primary and secondary schools during June 2020. FindingsThere were 67 single confirmed cases, 4 co-primary cases and 30 COVID-19 outbreaks during June 2020, with a strong correlation between number of outbreaks and regional COVID-19 incidence (0.51 outbreaks for each SARS-CoV-2 infection per 100,000 in the community; p=0.001). Overall, SARS-CoV-2 infections and outbreaks were uncommon across all educational settings. Staff members had an increased risk of SARS-CoV-2 infections compared to students in any educational setting, and the majority of cases linked to outbreaks were in staff. The probable transmission direction for the 30 confirmed outbreaks was: staff-to-staff (n=15), staff-to-student (n=7), student-to-staff (n=6) and student-to-student (n=2). InterpretationSARS-CoV-2 infections and outbreaks were uncommon in educational settings during the first month after the easing of national lockdown in England. The strong correlation with regional SARS-CoV-2 incidence emphasises the importance of controlling community transmission to protect educational settings. Additional interventions should focus on reducing transmission in and among staff members. Fundingnone


Subject(s)
COVID-19
11.
medrxiv; 2020.
Preprint in English | medRxiv | ID: ppzbmed-10.1101.2020.08.19.20177188

ABSTRACT

Background: Households appear to be the highest risk setting for transmission of COVID-19. Large household transmission studies were reported in the early stages of the pandemic in Asia with secondary attack rates ranging from 5-30% but few large scale household transmission studies have been conducted outside of Asia. Methods: A prospective case ascertained study design based on the World Health Organization FFX protocol was undertaken in the UK following the detection of the first case in late January 2020. Household contacts of cases were followed using enhanced surveillance forms to establish whether they developed symptoms of COVID-19, became confirmed cases and their outcomes. Household secondary attack rates and serial intervals were estimated. Individual and household basic reproduction numbers were also estimated. The incubation period was estimated using known point source exposures that resulted in secondary cases. Results: A total of 233 households with two or more people were included with a total of 472 contacts. The overall household SAR was 37% (95% CI 31-43%) with a mean serial interval of 4.67 days, an R0 of 1.85 and a household reproduction number of 2.33. We find lower secondary attack rates in larger households. SARs were highest when the primary case was a child. We estimate a mean incubation period of around 4.5 days. Conclusions: High rates of household transmission of COVID-19 were found in the UK emphasising the need for preventative measures in this setting. Careful monitoring of schools reopening is needed to monitor transmission from children.


Subject(s)
COVID-19
13.
medrxiv; 2020.
Preprint in English | medRxiv | ID: ppzbmed-10.1101.2020.05.18.20086157

ABSTRACT

Objectives: Following detection of the first virologically-confirmed cases of COVID-19 in Great Britain, an enhanced surveillance study was initiated by Public Health England to describe the clinical presentation, course of disease and identify risk factors for infection of the first few hundred cases. Methods: Information was collected on the first COVID-19 cases according to the First Few X WHO protocol. Case-control analyses of the sensitivity, specificity and predictive value of symptoms and risk factors for infection were conducted. Point prevalences of underlying health conditions among the UK general population were presented. Findings: The majority of FF100 cases were imported (51.4%), of which the majority had recent travel to Italy (71.4%). 24.7% were secondary cases acquired mainly through household contact (40.4%). Children had lower odds of COVID-19 infection compared with the general population. The clinical presentation of cases was dominated by cough, fever and fatigue. Non-linear relationships with age were observed for fever, and sensitivity and specificity of symptoms varied by age. Conditions associated with higher odds of COVID-19 infection (after adjusting for age and sex) were chronic heart disease, immunosuppression and multimorbidity. Conclusion: This study presents the first epidemiological and clinical summary of COVID-19 cases in Great Britain. The FFX study design enabled systematic data collection. The study was able to characterize the risk factors for infection with population prevalence estimates setting these relative risks into a public health context. It also provides important evidence for generating case definitions to support public health risk assessment, clinical triage and diagnostic algorithms.


Subject(s)
COVID-19 , Heart Diseases , Fever , Fatigue
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