Senior officials in Hertfordshire have called on residents to "act now" after a "significant rise" in Covid-19 cases in the county over the last ten days.

Director of public health Jim McManus and county council leader David Williams say there is a "limited window of opportunity" to stay in control of the spread of the virus in Hertfordshire – otherwise the county risks seeing tighter restrictions imposed.

Cases have been increasing across the county, particularly in the south, with more than 600 cases in October, prompting the council to issue a warning yesterday.

However, this paper understands misleading university student positive test results have inflated coronavirus rates in Hertfordshire recently by a third.

Public Health England is aware of a national issue where university students are having their cases registered at their home address rather than their university address - which means some areas are being made to look worse than they actually are.

Read more: Uni students 'hundreds of miles away' inflate number of coronavirus cases in Hertfordshire

According to the government dashboard, Three Rivers District Council has the highest weekly recorded rate of cases in Hertfordshire in the week ending October 9 with 107.2 cases per 100,000 population – with rates above 70 in Hertsmere, Watford, St Albans, and Dacorum.

These figures include supposed inflated rates from students.

Last week, Councillor Tim Hutchings, cabinet member for public health in Hertfordshire, said an increase in coronavirus rates in the county showed "no cause for undue concern" – but a statement issued by Mr McManus and Cllr Williams yesterday evening suggests the situation has now changed in Hertfordshire.

The statement read: "It has been announced that Hertfordshire, as a whole, has been placed as a medium-risk area in the government’s new system of Local Covid-19 Alert Levels.

"This means that Hertfordshire is currently rated in Tier One – the medium alert level. Despite this, we have seen a significant rise in positive cases of coronavirus in our county over the last 10 days and the situation here remains serious. There is no room for complacency.

"So we’re urging all of our residents to act now to avoid our county moving to high-risk status for which there will be stricter, tougher measures introduced."

St Albans & Harpenden Review:

Credit: PA

They continued: "We are properly prepared, and have a detailed plan in place to deal with each scenario. But now is the time to redouble our efforts to keep the virus at bay. We understand that many of our residents have been playing their part by following the government guidelines, particularly on face-coverings, social-distancing, the ‘rule of six’, and self-isolation where necessary.

"Yet, we are appealing to everyone to be even more disciplined to help us control the spread of the virus. Unless we act now, it is likely that the rate of infection will continue to rise - and that could mean further restrictions.

"We want to keep you, the residents of Hertfordshire, safe while also keeping the county up-and-running to support our businesses and our economy."

St Albans & Harpenden Review:

Credit: PA

The council says people not self-isolating when they should be has caused the virus to spread in Hertfordshire.

It said it was aware of instances of people who have been going to work or playing sport when they should be staying at home.

The statement continued: "Everyone must take responsibility now to lower the risks involved in all of the things we do in our day-to-day lives. Unless we do that, coronavirus could get a stronger grip than it has now.

"We still have a limited window of opportunity to stay in control of the spread of the virus in Hertfordshire, rather than having stricter measures implemented. We urge all of our residents to help us make sure that is the case by following the guidance. If you keep playing your part, we can all stay safe in Hertfordshire together."

NHS England data published today has shown another two deaths of patients at West Hertfordshire Hospitals NHS Trust who tested positive for Covid-19.

Both patients died on Saturday (October 10).

Eight Covid-19 deaths have now been reported by the trust in October - and ten in total since September 25.