An outbreak of Covid cases in a village near Watford is understood to be linked to a secondary school.

Towards the end of September, the infection rate in Chorleywood rocketed to the highest in Hertfordshire and quite possibly the highest in the south of England.

There were more than 70 cases recorded over a weekly period in mid-September in Chorleywood which was more than any other part of Three Rivers district.

The village infection rate was as high and the equivalent to 1,272 cases per 100,000 population but has now dropped to 764.0 – which is still one of the highest in the county.

The Observer understands the rise in cases was linked to St Clement Danes secondary school in Chorleywood, and a heatmap published on the Government Covid-19 dashboard shows the current highest rates in Three Rivers are by far in those aged 10 to 14.

Hertfordshire County Council public health director Jim McManus has issued a statement about the increase.

He said: "We are aware of higher infection rates in some parts of the community, including workplaces and schools. We’re working with all of these settings, and advising them on measures they can take to control infection numbers.

"We are aware of some schools with outbreaks, and head teachers, with advice from Public Health, are putting in additional measures in schools. We are continuing to advise students to wear face coverings to and from schools, as we believe this is where a number of the infections are taking place within school communities.

"We would also encourage anyone who is eligible to take up the offer of a Covid-19 vaccination, as this is the best protection against serious illness."

The weekly number of cases in Chorleywood has reduced – there were 40 cases recorded in the village in the seven days to September 28.

Neighbouring Little Chalfont and Amersham in Buckinghamshire continue to record higher levels of infections.

Chorleywood has the second highest uptake in Covid vaccinations in Three Rivers’ 12 wards with 84 per cent of the village's over 16 population fully vaccinated, and 88.7 per cent receiving one dose.

NHS England figures show as of September 30, 162 under 18s living in Chorleywood had received one dose of the Covid vaccine.

According to the Office for National Statistics (ONS), around 1 in 20 students at secondary schools in England are estimated to have had coronavirus in the week to September 25, with around 1 in 85 people in private households likely to have had Covid-19 in the same week.

All children aged 12 and over in the UK are now able to have a first dose of Covid-19 vaccine, which means those in school years 8 to 11 in England, as well as some in year 7, can get the jab.

Elsewhere, Leavesden & Garston Manor recorded the most Covid cases locally between September 22 and 28 with 54, followed by Bovingdon & Chipperfield and Chorleywood with 44 each, 40 in Radlett, 39 in Rickmansworth West, 35 in Croxley Green, and 30 in each of Cassiobury and Leggatts in Watford.