Asymptomatic people infected with Covid mixing with others indoors is currently the “single biggest cause” in spreading the virus, according to Hertfordshire’s top public health boss.

Monday marked the so-called “freedom day” in England when the country reached the last step in the Government’s unlocking road map.

Latest figures show that all 10 districts in Hertfordshire have seen a week-on-week rise in infection rates, with St Albans currently seeing the highest rate of 586 cases per 100,000 population.

Other districts in the county with a rate of over 500 cases per 100,000 population include Hertsmere, Three Rivers, East Hertfordshire and Dacorum.

With most restrictions eased, the Borehamwood Times asked Hertfordshire’s director of public health Jim McManus what the single biggest driver of coronavirus infections across the county is.

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He said: “The single biggest cause of spread at present is people with no symptoms getting too close to others indoors and infecting them through aerosol spread.

“Face coverings work to reduce that.”

Government dashboard data shows cases in Hertfordshire are being driven by teenagers and those in their 20s and early 30s.

As of July 13, there were 20 Covid patients being cared for by West Hertfordshire Hospitals NHS Trust, including two patients on ventilation.

The trust last recorded a Covid-19 death of July 8.

Speaking to the Times before ‘freedom day’, Mr McManus said: “The virus has not gone away, in fact cases are rising and it’s important to recognise that everyone’s circumstances are different and what feels comfortable to one person might not feel that way to another.”

He added: “The most important thing right now is for us all to keep doing the things which stop infection. Get vaccinated if you are 18 or over, give people space, wear face coverings in crowded indoor areas, ventilate your workplaces and social spaces, and if you have symptoms get tested and self-isolate. These measures have kept us safe and will keep us safe still.

 “Covid-19 won’t end when the rules change, and we need to keep being sensible – as almost everyone has been for the last 15 months – and keep each other safe.

 “Let’s keep looking out for one another and recognise that we’re all going to be moving forward at our own pace.”