Drop in level of norovirus winter vomiting bug cases

Image caption The virus can cause vomiting and diarrhoea

Levels of the winter vomiting bug norovirus have gone down for a second week, latest figures show.

But experts say the 32% drop seen in the rate of confirmed new cases over the last week alone in England and Wales does not mean the problem has gone away.

Infection rates always fluctuate and cases could easily rise again, says the Health Protection Agency (HPA).

This season, a new strain called Sydney 2012, is responsible for most cases.

This strain of the virus was first seen in Australia, where the norovirus season is lasting longer than usual as outbreaks continue into their summer.

Experts are watching international patterns closely but cannot be sure what will happen next in the UK.

The number of new cases are up 56% on the number reported this time last year, and the total lab-confirmed toll now stands at 4,407.

For each confirmed new case experts estimate a further 288 cases are likely to go unreported.

Hospital outbreaks

John Harris, an expert in norovirus at the HPA, said: "Norovirus activity always varies from year to year and although we might have expected cases to rise again now we have passed the new year period this hasn't been the case.

"We can't read anything into this fall and don't know how busy the rest of the season will be.

"The busiest months are normally from December to April, so further cases will occur but we can't say if there will be further significant increases in the number of laboratory reports."

During the two weeks up to 13 January 2013 there were 39 hospital outbreaks reported, compared to 33 in the previous fortnight, bringing the total of outbreaks for the season to 728.

The highly contagious virus can be spread by contact with contaminated surfaces or objects, contact with a person who has the infection or through contaminated food and water.

Experts advise anyone who thinks they may have the virus to stay away from hospitals, GP surgeries and care homes to avoid spreading it to people who may be vulnerable.

The illness usually resolves in a few days with no long-term effects.

More on this story

Around the BBC

Related Internet links

The BBC is not responsible for the content of external Internet sites