More than 10,000 school children in Hertfordshire have tested positive for COVID-19 since schools returned in September.

In the last week of the autumn half-term public health officials were dealing with ‘outbreaks’ at 198 of the county’s educational settings.

Data shows that since the start of term children aged between 10 and 14 have been the most likely to catch COVID-19 – with 7,723 testing positive between September 1 and October 20, but it also shows that there have been 3,236 cases among those aged between five and nine.

There were 3,699 cases recorded in those aged 15-19 – though this figure will also include young people who may have left school and be in employment or at university.

Many of these cases may not be connected to a child’s school or college.

An outbreak is typically where five or more pupils, students or staff (or 10 per cent of that group) – who are likely to have mixed closely – test positive for COVID-19 within a 10-day period.

Where outbreaks are identified public health officials advise schools, colleges or other settings on measures they can implement in a bid to halt any further spread.

In some cases this has included the temporary reintroduction of measures such as the wearing of face masks, ‘bubbles’ or one-way systems.

Director of public health Jim McManus said: “The government has made it a national priority that education and childcare settings should continue to operate as normally as possible.

“National guidelines state that children under 18 are no longer required to self-isolate if they are a close contact of someone who has tested positive.

“We are continuing to work closely with schools, to try to keep infections to a minimum, advising them of the additional measures they should take to control infection numbers, at the same time as supporting the roll-out of vaccinations amongst 12-15-year-olds.

“In some cases, this has included individual schools putting additional measures in place when dealing with a local outbreak, in line with Department for Education guidance.

“We continue to keep outbreaks in schools under close review and our schools’ COVID team remains available to advise every school on appropriate measures.”