Who Novel Virus Fact Sheet 30apr09

Fact-Sheet Novel A/H1N1 outbreak in Mexico and USA What is it? It is a new strain of Influenza virus A/H1N1. There have been reporting of influenza-like illness (ILI) and sever pneumonia cases in Mexico and USA. Cases began to appear on 17 March 2009 in Mexico. Two cases in children were reported in Southern California in USA on 17 April, 2009. Neither child had contact with animals. Between 17 March and now, clusters of outbreaks have appeared in multiple locations in Mexico and USA. These clusters are consistent with human-to-human spread. What are the characteristics of the virus? The virus causing this illness is being described in the USA as a new subtype of A/H1N1 not previously detected in swine or humans. Genetically it is a reassortant of AmericaEurasian swine influenza viruses. What is the current situation? As of 25 April 2009, 878 cases of severe pneumonia with 60 deaths were reported between 17 March to 25 April 2009 in Mexico. Samples are being tested to see if they are due to the new virus. A total of 7 laboratory confirmed cases of novel A/H1N1 have been reported in the US. Most of these cases had mild ILI. Who are affected? Most of the cases in Mexico have been found in healthy young adults between the age of 4 and 45 years old. In the USA, the cases range in age from 7 years to 54 years. How does it spread? It is believed to spread in the same way as seasonal influenza. That means through direct contact (being within one meter of an infected person) or indirect contact (touching a contaminated surface) What are the clinical symptoms? Patients experience high fever, cough, and sore throat, symptoms similar to typical influenza, with some patients experiencing diarrhoea and vomiting. The cases can rapidly progress to severe and unusual pneumonia. What medicines can be used for treatment of an infection by this new virus? This virus is susceptible to oseltamivir and zanamivir. The virus strain has been shown to be resistant to rimantadine and amantadine.

Does the seasonal influenza vaccine protect against this new influenza virus? We do not know yet if the H1N1 component of this season's influenza vaccine provides any protection against the new strain. Studies are under way to determine if there is any cross-protection.

What should people know? So far, cases have been reported from North America only. WHO will keep people informed if it spreads to other areas. What control measures should be implemented? Right now, people must be vigilant. Countries should ensure proper surveillance of severe or unusual pneumonia cases or of a sudden increase in ILI cases. In Mexico, the government closed the schools, universities and day cares and asked government employees to work from home. They also closed many public services in order to minimize the spread of disease. People are being reminded of the importance of frequent handwashing. People should follow cough etiquette and crowding should be avoided. What is WHO doing? WHO is in constant contact with health authorities in Member States and receiving regular updates. WHO has activated Strategic Health Operation Centers at HQ and Regional Offices. WHO Director General has convened a IHR Emergency Committee Meeting comprised of international experts to assess the situation and recommend response measures. WHO SEARO has alerted IHR Focal Points and WHO Contact Points at the country level and is providing technical guidance to Member countries. WHO has requested National Influenza Centers to assess their ability to detect H1N1 viruses. For more information, please contact: CSR SEARO Tel. No. +91 99585 90457 / 0112337 0804. Email: [email protected]

WHO HQ website: http://www.who.int/csr/don/2009_04_24/en/index.html CDC MMWR update on swine influenza A (H1N1) infections