A slight rise of Covid-19 cases reported in children is due to an increase in testing and not the reopening of schools, a senior health expert has said.
Professor Philip Nolan, chairman of the Irish Epidemiological Modelling Advisory Group, said that data shows schools remain a low-risk environment.
Prof Nolan said that a public health investigation looked at incidence of coronavirus infection in children in recent weeks, to assess the impact of the phased return of schoolchildren to the classroom.
He said that schools are low risk because of the mitigation and protection measures put in place by teachers, principals, families, general practitioners and public health doctors.
Schools will reopen to all students on Monday, marking the final phase of the Government’s plan to have all pupils back in the classroom.
First to fourth year secondary students will return to school for the first time since the Christmas holidays.
Health experts have been assessing the rate of Covid-19 cases detected in schools, as well as any wider impact of the increased movement of people.
Prof Nolan tweeted: “The data show a moderate and transient increase in cases of SARS-CoV-2 infection reported in children, not directly because of the return to in-person education, but due to increased detection, or case ascertainment, related to an increase in testing.
“During a surge, incidence in children is generally lower than the population average, but towards the end of the surge it converges with the population average.
“There have been two recent increases in incidence in children, in early February and mid-March.
“Specifically, during a surge, we first see incidence rising in 19-24 year olds, later and simultaneously in adults 25-64 year olds and teenagers, and later again in children, slowly converging on the population average towards the end of the surge.
“So what explains the recent changes in incidence in children? The first increase occurred in early February, just after we resumed testing of asymptomatic close contacts, which had been paused for most of January.” He said that children are more likely to be asymptomatic and the number of asymptomatic infections detected in children dropped sharply in January.
The resumption of close contact testing in February led to an increase in incidence.
The second increase in incidence rate happened in March, shortly after the first phase of reopening schools.
“While the level of testing increased 5 to 10 fold, the increase in detected infections was much smaller (40-50%), suggesting that the increase in incidence is in significant part due to the increase in testing,” he added.
“We note also that school opening is associated with an increase in attendance at workplaces; this increase in social mixing amongst adults carries a risk of increased viral transmission between households.”