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Home News centre National Press Releases 2013 Press Releases ›  HPA update on seasonal norovirus activity: 15 January 2013

HPA update on seasonal norovirus activity: 15 January 2013

15 January 2013

Latest figures from the Health Protection Agency (HPA) show there have been 4,407 laboratory confirmed cases of norovirus this season (from week 27 to week 01 2013). The latest figures are 56 per cent higher than the number of cases reported at this point last year, when there were 2,828 cases.

The report shows that there has been a continuation in the downward trend in the number of confirmed cases over the last week with a 32 per cent drop on the previous week (257 week 52 to 175 in week 01 2013). This shows the unpredictability of the norovirus season where the number of confirmed cases rises and falls. However, there will still be new cases arising before the season ends.

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

A new strain of norovirus called Sydney 2012 has been circulating this season. Although this was detected through HPA surveillance at the start of the season it was not the dominant strain at that time. Later testing has revealed that it is now the dominant strain. This could be an explanatory factor in why there was an early start to the season.

John Harris, an expert in norovirus from 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.

“There have been reports in the media of people with symptoms of norovirus attending their local hospital but we would urge people not to do this. If you think you may have the illness then it is important to stay away from any healthcare facility and care homes to avoid spreading it to people who may have underlying health conditions and already be vulnerable. If you need advice it is best to phone NHS Direct or your doctor.”

Norovirus can be transmitted by contact with contaminated surfaces or objects, by contact with an infected person, or by the consumption of contaminated food or water. Symptoms of norovirus include a sudden onset of vomiting and/or diarrhoea. Some people may have a temperature, headache and stomach cramps. The symptoms only last for a couple of days and there are no long-term effects. Maintaining good hand hygiene is also important to help prevent it spreading.


Notes to editors:

  1. Please note: In future the weekly norovirus report will be published on a Thursday to coincide with the HPA’s Winter Pressures report. This report encompasses information about flu and other respiratory diseases. This will come out at 2pm every Thursday.
  2. Indications from Europe and Japan are that norovirus activity also started to increase early. In Australia the norovirus season also peaks during the winter but this season it has gone on longer than usual and they are seeing cases into their summer. The HPA is following up with colleagues internationally.
  3. The number of laboratory confirmed cases represents just a fraction of the actual amount of norovirus activity as it is estimated that for each confirmed case, there are a further 288 unreported cases, as the vast majority of those affected do not seek healthcare services in response to their illness. Data from The Infectious Intestinal Diseases II (IID II) report can be found at the Food Standards Agency website [external link].
  4. Guidelines for the management of norovirus in acute and community health and social care settings can be found from the Guidelines for the management of norovirus outbreaks in acute and community health and social care settings (PDF, 2.6 MB)  document.
  5. The latest norovirus report can be found from the Norovirus update: 10 July 2014 (PDF, 707 KB) document.
  6. For further information about Norovirus see the HPA website's Norovirus page.
  7. The Health Protection Agency is an independent UK organisation that was set up by the government in 2003 to protect the public from threats to their health from infectious diseases and environmental hazards. In April 2013, subject to the usual approvals procedures for establishing new bodies, the Health Protection Agency will become part of a new organisation called Public Health England, an executive agency of the Department of Health. To find out more, visit our website: or follow us on Twitter @HPAuk or ‘Like’ us on Facebook at [external link].
  8. For more information please contact the national HPA press office at Colindale on 0208 327 7901 or email Out of hours the duty press officer can be contacted on 0208 200 4400.

Last reviewed: 15 January 2013