Researchers working on behalf of NHS England have found no evidence that adults living with school-age children are infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) – the causative agent of the coronavirus – Have an increased risk of serious consequences Illness 2019 (COVID-19).
The large population-based study was conducted by researchers from the London School of Hygiene and Tropical Medicine (LSHTSM), Oxford University, and the Phoenix Partnership to examine growing concerns that children could serve as the main reservoir for the spread of SARS-CoV-2.
“This is the first population-based study to assess whether the risk of recorded SARS-CoV-2 infection and the serious consequences of COVID-19 differ between adults living in households with and without children during the UK pandemic of school age, “writes the team.
In working-age adults (65 years or younger), living with children 0-11 years of age was not at increased risk of SARS compared to working-age adults living with children 0-11 years old -CoV-2 infections or COVID-19-related hospital stays linked did not live with children.
In this age group, living with children aged 12 to 18 years was associated with a slightly increased risk of infection, but not with COVID-19 results. Additionally, living with children of all ages reduced the risk of death from causes unrelated to COVID-19.
In adults over 65 years of age, no associations were found between living with children and SARS-CoV-2-related results.
Laurie Tomlinson and colleagues say the results will have implications for determining the benefit versus harm to children attending school while the pandemic continues.
A pre-print version of the paper is available on the medRxiv * server while the article is being peer reviewed.
The role children play in transmission is unclear
Model studies of other respiratory infections have shown that children are a major source of spread in the early stages of an epidemic, in part due to their high level of social engagement.
However, growing body of evidence suggests that in the case of SARS-CoV-2, children are less susceptible, less infectious, and no more likely than adults to transmit the virus.
One proposed mechanism for lower susceptibility in children is cross-reactive immunity to SARS-CoV-2, acquired through infection with seasonal human coronaviruses (hCoVs). These infections, which cause colds, are more common in children than adults, with the highest rates of infection seen in young children.
“If the recent hCoV infection protects against SARS-CoV-2 infection, or COVID-19, adults with children may be less at risk than children without children,” said Tomlinson and his team.
On the flip side, children could introduce SARS-CoV-2 into their households, and adults who live in close contact with children could be at increased risk of infection, they add.
“With transmission increasing in many countries and the need for policy decisions about school opening, it is important to quantify the overall impact of living with children on the risk of SARS-CoV-2 infection and the serious consequences of COVID-19,” you write the explorers.
What did the team do?
Tomlinson and colleagues used UK electronic health records linked to data on household members to investigate the risk of SARS-CoV-2 infection and severe COVID-19 outcomes between adults living with children and those who don’t do this was different.
The study used primary care data and linked information on hospital admissions and intensive care units (ICU) and death certificates from patients enrolled with general practitioners who represented 40% of England.
The team used multivariate Cox regression to calculate outcome risk between February 1 and August 3, 2020 after gender, age, multiple deprivation index, body mass index, smoking status, ethnicity, and number of adults were taken into account in the budget.
The last cohort included 9,157,814 adults of working age (65 years and younger) and 2,567,671 adults over the age of 65.
What did the researchers find?
In working-age adults, sharing a house with children aged 0-11 was not associated with an increased risk of recorded SARS-CoV-2 infection or COVID-19-related hospitalization or intensive care. However, the team observed a 25% reduced risk of COVID-19-related death.
In the same age group, living with children aged 12 to 18 years was associated with an 8% increased risk of recorded SARS-CoV-2 infection, but not an increased risk of other COVID-19 outcomes. Living with children of all ages has also been linked to a reduced risk of death from causes unrelated to COVID-19.
In adults over 65 years of age, regardless of the age group of the children, there was no evidence of an association between living with children and the results associated with SARS-CoV-2.
In all analyzes, an additional adjustment for comorbidities did not significantly change the results, and no consistent differences in infection risk or serious results were observed when the periods before and after school ended.
The results have important implications
“Our results show no evidence of serious harm from COVID-19 to adults in close contact with children compared to those who live in households without children,” the researchers write.
“These results, among other findings, have an impact on determining the benefit-harm ratio of children who go to school during the COVID-19 pandemic,” the team concludes.
* Important NOTE
medRxiv publishes preliminary scientific reports that are not peer-reviewed and, therefore, should not be considered conclusive, guide clinical practice / health-related behavior, or treated as established information.