Effectiveness of BNT162b2 and ChAdOx1 against SARS-CoV-2 household transmission - a prospective cohort study in England

Background: The ability of SARS-CoV-2 vaccines to protect against infection and onward transmission determines whether immunisation can control global circulation. We estimated effectiveness of BNT162b2 and ChAdOx1 vaccines against acquisition and transmission of the Alpha and Delta variants in a prospective household study in England. Methods: Adult index cases in the community and their household contacts took oral-nasal swabs on days 1, 3 and 7 after enrolment. Swabs were tested by RT-qPCR with genomic sequencing conducted on a subset. We used Bayesian logistic regression to infer vaccine effectiveness against acquisition and transmission, adjusted for age, vaccination history and variant. Findings: Between 2 February 2021 and 10 September 2021 213 index cases and 312 contacts were followed up. After excluding households lacking genomic proximity (N=2) or with unlikely serial intervals (N=16), 195 households with 278 contacts remained of whom 113 (41%) became PCR positive. Delta lineages had 1.64 times the risk (95% Credible Interval: 1.15-2.44) of transmission than Alpha; contacts older than 18 years were 1.19 times (1.04-1.52) more likely to acquire infection than children. Effectiveness of two doses of BNT162b2 against transmission of Delta was 31% (-3%, 61%) and 42% (14%, 69%) for ChAdOx1, similar to their effectiveness for Alpha. Protection against infection with Alpha was higher than for Delta, 71% (12%,95%) vs 24% (-2%, 64%) respectively for BNT162b2 and 26% (-39%, 73%) vs 14% (-5%, 46%) respectively for ChAdOx1. Interpretation: BNT162b2 and ChAdOx1 reduce transmission of the Delta variant from breakthrough infections in the household setting though their protection against infection is low. Funding: This study was funded by the UK Health Security Agency (formerly Public Health England) as part of the COVID-19 response.

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Impact of BNT162b2 vaccination and isolation on SARS-CoV-2 transmission in Israeli households: an observational study

10.1101/2021.07.12.21260377 ◽

2021 ◽

Author(s):

Maylis Layan ◽

Mayan Gilboa ◽

Tal Gonen ◽

Miki Goldenfeld ◽

Lilac Meltzer ◽

...

Keyword(s):

Healthcare Workers ◽

Data Augmentation ◽

Medical Center ◽

Credible Interval ◽

Control Measures ◽

Risk Of Infection ◽

Household Transmission ◽

Index Cases

Background Massive vaccination rollouts against SARS-CoV-2 infections have facilitated the easing of control measures in countries like Israel. While several studies have characterized the effectiveness of vaccines against severe forms of COVID-19 or SARS-CoV-2 infection, estimates of their impact on transmissibility remain limited. Here, we evaluated the role of vaccination and isolation on SARS-CoV-2 transmission within Israeli households. Methods From December 2020 to April 2021, confirmed cases were identified among healthcare workers of the Sheba Medical Centre and their family members. Households were recruited and followed up with repeated PCR for a minimum of ten days after case confirmation. Symptoms and vaccination information were collected at the end of follow-up. We developed a data augmentation Bayesian framework to ascertain how age, isolation and BNT162b2 vaccination with more than 7 days after the 2nd dose impacted household transmission of SARS-CoV-2. Findings 210 households with 215 index cases were enrolled. 269 out of 687 (39%) household contacts developed a SARS-CoV-2 infection. Of those, 170 (63%) developed symptoms. Children below 12 years old were less susceptible than adults/teenagers (Relative Risk RR=0.50, 95% Credible Interval CI 0.32-0.79). Vaccination reduced the risk of infection among adults/teenagers (RR=0.19, 95% CI 0.07-0.40). Isolation reduced the risk of infection of unvaccinated adult/teenager (RR=0.11, 95% CI 0.05-0.19) and child contacts (RR=0.16, 95% CI 0.07-0.31) compared to unvaccinated adults/teenagers that did not isolate. Infectivity was significantly reduced in vaccinated cases (RR=0.22, 95% CI 0.06-0.70). Interpretation Within households, vaccination reduces both the risk of infection and of transmission if infected. When contacts were not vaccinated, isolation also led to important reductions in the risk of transmission. Vaccinated contacts might reduce their risk of infection if they isolate, although this requires confirmation with additional data. Funding Sheba Medical Center.

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Household transmission of seasonal coronavirus infections: Results from the Flu Watch cohort study

Wellcome Open Research ◽

10.12688/wellcomeopenres.16055.1 ◽

2020 ◽

Vol 5 ◽

pp. 145 ◽

Cited By ~ 2

Author(s):

Sarah Beale ◽

Dan Lewer ◽

Robert W. Aldridge ◽

Anne M. Johnson ◽

Maria Zambon ◽

...

Keyword(s):

Cohort Study ◽

Index Case ◽

Transmission Risk ◽

Related Factors ◽

Household Transmission ◽

Clinical Onset ◽

Using Data ◽

The Uk ◽

The Impact ◽

Index Cases

Background: In the context of the current coronavirus disease 2019 (COVID-19) pandemic, understanding household transmission of seasonal coronaviruses may inform pandemic control. We aimed to investigate what proportion of seasonal coronavirus transmission occurred within households, measure the risk of transmission in households, and describe the impact of household-related factors of risk of transmission. Methods: Using data from three winter seasons of the UK Flu Watch cohort study, we measured the proportion of symptomatic infections acquired outside and within the home, the household transmission risk and the household secondary attack risk for PCR-confirmed seasonal coronaviruses. We present transmission risk stratified by demographic features of households. Results: We estimated that the proportion of cases acquired outside the home, weighted by age and region, was 90.7% (95% CI 84.6- 94.5, n=173/195) and within the home was 9.3% (5.5-15.4, 22/195). Following a symptomatic coronavirus index case, 14.9% (9.8 - 22.1, 20/134) of households experienced symptomatic transmission to at least one other household member. Onward transmission risk ranged from 11.90% (4.84-26.36, 5/42) to 19.44% (9.21-36.49, 7/36) by strain. The overall household secondary attack risk for symptomatic cases was 8.00% (5.31-11.88, 22/275), ranging across strains from 5.10 (2.11-11.84, 5/98) to 10.14 (4.82- 20.11, 7/69). Median clinical onset serial interval was 7 days (IQR= 6-9.5). Households including older adults, 3+ children, current smokers, contacts with chronic health conditions, and those in relatively deprived areas had the highest transmission risks. Child index cases and male index cases demonstrated the highest transmission risks. Conclusion: Most seasonal coronaviruses appear to be acquired outside the household, with relatively modest risk of onward transmission within households. Transmission risk following an index case appears to vary by demographic household features, with potential overlap between those demonstrating the highest point estimates for seasonal coronavirus transmission risk and COVID-19 susceptibility and poor illness outcomes.

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Emergence of the Delta Variant and risk of SARS-CoV-2 infection in secondary school students and staff: prospective surveillance in 18 schools, England

10.1101/2021.12.10.21267583 ◽

2021 ◽

Author(s):

Shamez N. Ladhani ◽

Georgina Ireland ◽

Frances Baawuah ◽

Joanne Beckmann ◽

Ifeanyichukwu O Okike ◽

...

Keyword(s):

Secondary Schools ◽

Infection Rates ◽

Prospective Surveillance ◽

School Students ◽

Health Security ◽

Nasal Swabs ◽

The Uk ◽

Academic Year ◽

Community Infection

ABSTRACTBackgroundThe role of educational settings on SARS-CoV-2 infection and transmission remains controversial. We investigated SARS-CoV-2 infection, seroprevalence and seroconversions rates in secondary schools during the 2020/21 academic year, which included the emergence of the more transmissible Alpha and Delta variants, in England.MethodsThe UK Health Security Agency (UKHSA) initiated prospective surveillance in 18 urban English secondary schools. Participants had nasal swabs for SARS-CoV-2 RT-PCR and blood sampling for SARS-CoV-2 Nucleoprotein and Spike protein antibodies at the start (Round 1: September-October 2020) and end (Round 2: December 2021) of the autumn term, when schools reopened after national lockdown was imposed in January 2021 (Round 3: March-April) and end of the academic year (Round 4: May-July).FindingsWe enrolled 2,314 participants (1277 students, 1037 staff). In-school testing identified 31 PCR-positive participants (20 students, 11 staff). Another 247 confirmed cases (112 students, 135 staff) were identified after linkage with national surveillance data, giving an overall positivity rate of 12.0% (278/2313; staff [14.1%, 146/1037] vs students [10.3%, 132/1276; p=0.006). Nucleoprotein-antibody seroprevalence increased for students and staff between Rounds 1-3 but changed little in Round 4, when the Delta variant was the dominant circulating strain. Overall, Nucleoprotein-antibody seroconversion was 18.4% (137/744) in staff and 18.8% (146/778) in students, while Spike-antibody seroconversion was higher in staff (72.8% (525/721) than students (21.3%, 163/764) because of vaccination.InterpretationSARS-CoV-2 infection and transmission in secondary schools remained low when community infection rates were low because of national lockdown, even after the emergence of the Delta variantFundingDHSC

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The Where is Norovirus Control Lost (WINCL) Study: an enhanced surveillance project to identify norovirus index cases in care settings in the UK and Ireland

Journal of Infection Prevention ◽

10.1177/1757177415613133 ◽

2015 ◽

Vol 17 (1) ◽

pp. 8-14 ◽

Cited By ~ 5

Author(s):

Evonne T Curran ◽

Jennie Wilson ◽

Caroline E Haig ◽

Colin McCowan ◽

Alistair Leanord ◽

...

Keyword(s):

The Uk ◽

Index Cases

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Impact of mass vaccination on SARS-CoV-2 infections among the total multiple sclerosis population receiving immunomodulatory disease-modifying therapies in England

10.21203/rs.3.rs-1016584/v1 ◽

2021 ◽

Author(s):

Nikos Evangelou ◽

Afagh Garjani ◽

Sameer Patel ◽

Dhiren Bharkhada ◽

Waqar Rashid ◽

...

Keyword(s):

Multiple Sclerosis ◽

General Population ◽

Mass Vaccination ◽

Test Results ◽

Health Security ◽

Disease Modifying Therapies ◽

Multiple Sclerosis Population ◽

Impaired Immune Response ◽

Disease Modifying ◽

The Uk

Abstract This study aimed to understand changes in the risk of SARS-CoV-2 infection among all people with multiple sclerosis (MS) receiving immunomodulatory disease-modifying therapies (DMTs) in England, compared to the general population, following mass vaccination. Longitudinal data collected by the National Health Service (NHS) England on all MS DMT prescriptions and the UK Health Security Agency on all registered SARS-CoV-2 test results were analysed. The incidence rate ratio of SARS-CoV-2 infection among people with MS taking DMTs compared to the general population was calculated before (November 2020-January 2021) and after (July-August 2021) mass vaccination. Risk of SARS-CoV-2 infection among people on ocrelizumab or fingolimod compared to the general population increased following liberalisation of COVID-19 restrictions (during March-July 2021) despite mass vaccination. No changes were found with other DMTs. These findings converge with the impaired immune response to vaccines observed with ocrelizumab and fingolimod.

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P353 Assessing compliance to screening for infectious diseases and vaccination in patients newly diagnosed with inflammatory bowel disease

Journal of Crohn s and Colitis ◽

10.1093/ecco-jcc/jjz203.482 ◽

2020 ◽

Vol 14 (Supplement_1) ◽

pp. S336-S337

Author(s):

R Pringle ◽

A Assadsangabi

Keyword(s):

Inflammatory Bowel Disease ◽

Infectious Diseases ◽

Bowel Disease ◽

Clinic Visit ◽

Varicella Zoster ◽

Vaccination Rates ◽

Vaccination History ◽

Inflammatory Bowel ◽

The Subject ◽

The Uk

Abstract Background Patients are frequently counselled on vaccinations and screened for infectious diseases prior to starting immune-modulating therapy; however, the most up-to-date ECCO guideline on the subject (1) recommends vaccination screening and completion at diagnosis. We assessed adherence to the ECCO guidelines in patients diagnosed with inflammatory bowel disease (IBD). Methods Medical records from 100 IBD patients up to 6 months of their diagnosis were analysed retrospectively at a tertiary IBD centre in the UK. Data were collected for infectious diseases screening, documentation of vaccination history and education/advice on vaccination. Vaccination rates for diphtheria, tetanus, pertussis, polio, hepatitis B, human papillomavirus (HPV), influenza, pneumococcal and varicella-zoster were documented if they were recorded in the medical notes. Results A total of 84% of patients were not screened for infectious diseases at diagnosis or within 6 months. Overall, 97% had no vaccination history documented and 97% were not advised to attend their GPs for vaccinations. Conclusion Despite the existence of international guidelines, poor compliance to vaccination in patients with IBD has been shown in line with previous reports (2). This suboptimal vaccination compliance could be partly due to poor documentation and the retrospective method of data collection. However, there is clearly an urgent need for education and execution of vaccination guidelines in IBD. This implementation of work is now ongoing at our unit through automatic formal standard vaccination notification on every IBD clinic visit, which will be further re-audited in 6 months’ time.

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Understanding the long-term concentration, flux, composition and processing of dissolved organic carbon in UK rivers

10.5194/egusphere-egu2020-6885 ◽

2020 ◽

Author(s):

Fred Worrall ◽

Nicholas Howden ◽

Timothy Burt

Keyword(s):

Organic Matter ◽

Organic Carbon ◽

Dissolved Organic Matter ◽

Dissolved Organic Carbon ◽

Sewage Treatment ◽

Resource Limitation ◽

Credible Interval ◽

Bayesian Hierarchical ◽

Doc Flux ◽

The Uk

Dissolved organic carbon (DOC) represents an important component of the terrestrial and fluvial carbon cycle as it represents a flux from terrestrial carbon stores and while it transfers through the fluvial network it can be processed to release greenhouse gases to the atmosphere. Furthermore, DOC is a major water resource limitation as the dissolved organic matter has to be removed prior to treatment. Therefore, we need to understand the concentration and fluxes of DOC and they change across a landscape between the terrestrial source and the tidal limit.Our ability to understand the processing of terrestrial and fluvial carbon has been limited by the range of catchments that have been considered and the time scale over which they have been considered. Studies focused on similar catchment types and very little means of comparing between catchments. However, if we can access and understand large datasets we can find general principles which control DOC and the relative importance of these controls. In this study we use two datasets. The first, is a dataset sampled across the UK for major rivers (270 catchments) from 1974 and this dataset is ideal for understanding flux to the continental shelf and this dataset has over 50000 datapoints. Secondly, many of these sites are monitored for a rang e of other parameters that are related to the composition of the dissolved organic matter. The important covariates for DOM composition are BOD, which is a measure of DOM decomposition, and COD which is measure of the oxidation state of the DOM. All the study catchments could be characterised by a range of covariate information, eg. soil cover, land use, hydro-climatology. To make maximum use of this data the dataset was considered within a Bayesian hierarchical framework.The concentrations of DOC from the UK rose for the 1974 on to the late 1990s before a decline to 2007-08. The decline was driven by changes in urban sources, particular by improvements in sewage treatment. The DOC flux from the UK has declined since a peak in 2000 and in 2017 was 767 ktonnes C/yr (95% credible interval 644 &#8211; 909 ktonnesC/yr). Modelling composition turnover gives the DOC flux from source as 3.5 Mtonnes C/yr with 2.6 Mtonnes C/yr lost to atmosphere (14 Mtonnes CO2eq/yr = 59 tonnes CO2eq/km2/yr).

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The role of multi-generational household clusters in COVID-19 in England

10.1101/2021.11.22.21266540 ◽

2021 ◽

Author(s):

Simon Thelwall ◽

Asad Zaidi ◽

Olisaeloka Nsonwu ◽

Wendy Rice ◽

Dimple Chudasama ◽

...

Keyword(s):

Population Density ◽

Relative Deprivation ◽

Demographic Data ◽

Population Level ◽

Cross Sectional ◽

Health Security ◽

White Ethnicity ◽

Household Transmission ◽

Patient Demographic Data ◽

Cross Sectional Design

Background Household transmission has been demonstrated to be an important factor in the population-level growth of COVID-19. UK Health Security Agency (UKHSA) maintains data on positive tests for COVID-19 and the residential addresses of cases. We sought to use this information to characterise clusters of COVID-19 in multi-generational households in England. Methods Using cross-sectional design, cases of COVID-19 were assigned to clusters if they occurred in the same residential property in a 14-day rolling window. Patient demographic data were supplemented with reference to the ONS index of multiple deprivation and population density. Multi-generational households were defined as a cluster with at least three people, with one case in a person who was 0-16 years old and one case in a person who was ≥ 60 years old, with at least 16 years between two members of each age group. Results A total of 3,647,063 COVID-19 cases were reported between 01 April 2020 and 20 May 2021. Of these, 1,980,527 (54.3 %) occurred in residential clusters. Multi-generational households formed 1.5 % of clusters, with these more likely to occur in areas of higher population density and higher relative deprivation. Multi-generational clusters were more common among households of non-White ethnicity and formed larger clusters than non-multi-generational clusters (median cluster size 6, IQR 4-11 vs 3, IQR 3-4, respectively). Conclusion Multi-generational clusters were not highly prevalent in England during the study period, however were more common in certain populations.

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Presence of DNA from Chlamydia-like organisms in the nasal cavities of grey seal pups (Halichoerus grypus) and three different substrates present in a breeding colony

BMC Veterinary Research ◽

10.1186/s12917-021-03032-3 ◽

2021 ◽

Vol 17 (1) ◽

Author(s):

Mark P. Dagleish ◽

Allen F. Flockhart ◽

Johanna L. Baily ◽

Ailsa J. Hall ◽

T. Ian Simpson ◽

...

Keyword(s):

Marine Mammals ◽

Anthropogenic Impacts ◽

Grey Seal ◽

Opportunistic Pathogens ◽

Human Waste ◽

Marine Food Webs ◽

Run Off ◽

Nasal Swabs ◽

Human Habitation ◽

The Uk

Abstract Background Chlamydia-like organisms (CLO) have been found to be present in many environmental niches, including human sewage and agricultural run-off, as well as in a number of aquatic species worldwide. Therefore, monitoring their presence in sentinel wildlife species may be useful in assessing the wider health of marine food webs in response to habitat loss, pollution and disease. We used nasal swabs from live (n = 42) and dead (n = 50) pre-weaned grey seal pups and samples of differing natal substrates (n = 8) from an off-shore island devoid of livestock and permanent human habitation to determine if CLO DNA is present in these mammals and to identify possible sources. Results We recovered CLO DNA from 32/92 (34.7%) nasal swabs from both live (n = 17) and dead (n = 15) seal pups that clustered most closely with currently recognised species belonging to three chlamydial families: Parachlamydiaceae (n = 22), Rhabdochlamydiaceae (n = 6), and Simkaniaceae (n = 3). All DNA positive sediment samples (n = 7) clustered with the Rhabdochlamydiaceae. No difference was found in rates of recovery of CLO DNA in live versus dead pups suggesting the organisms are commensal but their potential as opportunistic secondary pathogens could not be determined. Conclusion This is the first report of CLO DNA being found in marine mammals. This identification warrants further investigation in other seal populations around the coast of the UK and in other areas of the world to determine if this finding is unique or more common than shown by this data. Further investigation would also be warranted to determine if they are present as purely commensal organisms or whether they could also be opportunistic pathogens in seals, as well as to investigate possible sources of origin, including whether they originated as a result of anthropogenic impacts, including human waste and agricultural run-off.

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Estimating the effect of the 2005 change in BCG policy in England: a retrospective cohort study, 2000 to 2015

Eurosurveillance ◽

10.2807/1560-7917.es.2019.24.49.1900220 ◽

2019 ◽

Vol 24 (49) ◽

Cited By ~ 1

Author(s):

Sam Abbott ◽

Hannah Christensen ◽

Nicky J. Welton ◽

Ellen Brooks-Pollock

Keyword(s):

High Risk ◽

Labour Force ◽

Demographic Data ◽

Credible Interval ◽

Incidence Rates ◽

School Age Children ◽

School Age ◽

Bcg Vaccination ◽

The Uk ◽

The Impact

Background In 2005 in England, universal Bacillus Calmette–Guérin (BCG) vaccination of school-age children was replaced by targeted BCG vaccination of high-risk neonates. Aim Estimate the impact of the 2005 change in BCG policy on tuberculosis (TB) incidence rates in England. Methods We conducted an observational study by combining notifications from the Enhanced Tuberculosis Surveillance system, with demographic data from the Labour Force Survey to construct retrospective cohorts relevant to both the universal and targeted vaccination between 1 January 2000 and 31 December 2010. We then estimated incidence rates over a 5-year follow-up period and used regression modelling to estimate the impact of the change in policy on TB. Results In the non-United Kingdom (UK) born, we found evidence for an association between a reduction in incidence rates and the change in BCG policy (school-age incidence rate ratio (IRR): 0.74; 95% credible interval (CrI): 0.61 to 0.88 and neonatal IRR: 0.62; 95%CrI: 0.44 to 0.88). We found some evidence that the change in policy was associated with an increase in incidence rates in the UK born school-age population (IRR: 1.08; 95%CrI: 0.97 to 1.19) and weaker evidence of an association with a reduction in incidence rates in UK born neonates (IRR: 0.96; 95%CrI: 0.82 to 1.14). Overall, we found that the change in policy was associated with directly preventing 385 (95%CrI: −105 to 881) cases. Conclusions Withdrawing universal vaccination at school age and targeting vaccination towards high-risk neonates was associated with reduced incidence of TB. This was largely driven by reductions in the non-UK born with cases increasing in the UK born.

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