9 January 2013
A scientific paper published in Eurosurveillance on January 3 described a new variant of norovirus (genotype G11 – 4) called Sydney 2012.
As part of its surveillance for norovirus the Health Protection Agency (HPA) carries out genetic testing of norovirus strains from cases in England and Wales.
Testing carried out when cases started to rise in October revealed a cocktail of different strains that were circulating including Sydney 2012 and another called New Orleans 2009, although no one strain was dominant.
The latest testing of the most recent outbreaks, completed this week, has now shown that Sydney 2012 has overtaken all others to become the dominant strain.
Syndey 2012 was first seen in Australia (and takes its name from the place it was first identified) and has also been seen in France, New Zealand and Japan.
This new strain does not cause more serious illness than others and the methods of managing cases and outbreaks are the same for any strain of norovirus. These measures include washing the hands thoroughly and regularly particularly after using the toilet and before eating.
Dr David Brown, Director of Virology Reference Department at the HPA said, “It is always difficult to predict the norovirus season and this year is no different.
“Noroviruses mutate rapidly and new strains are constantly emerging. At the start of the season it is normal for outbreaks to be caused by a range of different strains. However as the season progresses particular strains are more successful and become dominant. The emergence of a new strain does not mean that it causes more serious illness and managing outbreaks and those will the illness remains the same.
“There is no specific treatment for norovirus infection other than to let the illness take its course, with symptoms usually lasting around two days. Keeping hydrated is very important and you can take over-the-counter medicines to relieve headaches and aches and pains.”
1. The latest norovirus report can be found from the Norovirus update (PDF, 187 KB) document.
2. The Eurosurveillance paper can be found from the Eurosurveillance website [external link].
3. 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: http://www.hpa.org.uk or follow us on Twitter @HPAuk or ‘Like’ us on Facebook at www.facebook.com/HealthProtectionAgency
4. For more information please contact the national HPA press office at Colindale on 0208 327 7901 or email firstname.lastname@example.org. Out of hours the duty press officer can be contacted on 0208 200 4400.
Last reviewed: 9 January 2013