A surge in winter vomiting bug outbreaks is expected as schools prepare to welcome pupils back to classrooms next week, Public health experts have warned.

Norovirus, which is highly infectious and causes vomiting and diarrhoea, is normally associated with the winter months.

However, cases of the bug are currently increasing across England and “it is possible that unusual or out-of-season increases could be seen in the coming months following further easing of Covid-19 control measures”, Public Health England (PHE) said.

There has been a concentration of outbreaks particularly in nursery and childcare facilities, with far more incidents reported to PHE than would be expected in the summer months.

Warning to families and teachers

Routine surveillance earlier in the summer showed that cases started to increase in June, and have been “notably higher” in children aged under five, with early year educational settings among the worst for spreading the bug.

In July, cases were “43 per cent higher than the average of the previous five seasons prior to the emergence of Covid-19”, PHE said.

The health body is now warning that further outbreaks are likely in the coming months and is urging families and teachers to take precautions.

Dr Lesley Larkin, surveillance lead for the Gastrointestinal Pathogens Unit at PHE, said: “We have seen increases in norovirus cases as Covid-19 restrictions have eased and people mix more.

“As children head back to school next week, it’s important to remember simple steps we can all take to limit the spread of this unpleasant bug and reduce the chances of outbreaks.

“Stay at home if you are experiencing norovirus symptoms and do not return to work or send children to school or nursery until 48 hours after symptoms have cleared.

“As with Covid-19, handwashing is really important to help stop the spread of this bug, but remember, unlike for Covid-19 alcohol gels do not kill off norovirus so soap and water is best.”

What is norovirus and is it contagious?

Norovirus, commonly known as the winter vomiting bug, is a highly contagious stomach bug which causes vomiting and diarrhoea.

The virus is easily transmitted through close contact with people who have been infected, or by touching contaminated surfaces.

It can also be spread by eating food that has been prepared or handled by someone with the bug.

While the virus can be very unpleasant, it usually passes in a couple of days.

What is the incubation period?

The onset of symptoms usually starts suddenly within 24 to 48 hours after contracting the bug, although they can appear as early as 12 hours after exposure in some cases.

What are the symptoms?

The main symptoms of norovirus typically include:

  • feeling sick (nausea)
  • diarrhoea
  • being sick (vomiting)

Other common symptoms can include a high temperature, a headache and aching arms and legs.

How is it treated?

The best way to treat norovirus is to get plenty of rest and drink lots of fluids to avoid dehydration.

Symptoms will usually pass in around two to three days.

As the bug is highly contagious, it is advised that you stay at home until 48 hours after symptoms stop to prevent passing the bug on.

What precautions can I take?

PHE has urged people to take five simple precautions to help reduce the risk of contracting and spreading the virus.

These include:

  • Staying at home until 48 hours after symptoms stop.
  • Washing your hands frequently with soap. Alcohol gels do not kill norovirus.
  • Making sure you thoroughly clean all surfaces after a person has been sick.
  • Avoiding cooking and preparing meals for 48 hours after symptoms have stopped.
  • Washing any clothing or bedding using detergent and a temperature of 60C.