What is swine flu? Swine flu is a respiratory disease in pigs, caused by one of several swine influenza A viruses. The symptoms are the same as regular flu: fever, cough, tiredness, muscle aches, sore throat, shortness of breath, runny nose, headache and sometimes vomiting and diarrhoea.What should I do if I think I have swine flu? Contact your local public health unit, or general practitioner, or go to your nearest emergency department. If you have visited a country with confirmed cases of swine flu since March and are unwell with a respiratory illness (fever and cough), contact your GP by telephone. If swine flu is suspected, you will be asked to isolate yourself from others to prevent further infection. In Victoria, three schools have been closed after cases of swine flu were confirmed among pupils. Pupils diagnosed with the virus have been told to remain in quarantine at home.How is the disease treated? Standard flu vaccinations do not protect against swine flu and there is no evidence that wearing a mask will guard against infections. A vaccination is available for pigs, but not humans. Tamiflu and Relenza (which prevent the virus from reproducing) are recommended for treating or preventing infection and Australia has a stockpile of 8.7 million courses. In most reported swine flu cases a full recovery has been made without medical intervention.When can we expect a vaccine for swine flu? A number of pharmaceutical companies are working on vaccines; Melbourne-based drug manufacturer CSL has indicated it could produce a swine flu-specific vaccine in nine weeks.Are you immune once you get it? There's a high probability you will have immunity once infected. However, in the 1918 Spanish flu pandemic some people were infected twice.What are the chances of the virus mutating to a more virulent strain?This is a possibility, especially as we head into the winter months because influenza spreads more easily in winter. Much is still unknown about this new strain and how easily it spreads between people.Is it safe to travel? The Department of Foreign Affairs and Trade recommends Australians reconsider any plans to travel to Mexico due to outbreaks of swine flu. It is regularly updating its travel advice for other countries. Visit www.smarttraveller.gov.au for details.Who is most affected by the disease? Children under 18 will be most affected as they have no existing immunity to the virus. It appears that adults, particularly the elderly, have some immunity to H1N1 swine flu.For more information: Call Wollongong Public Health unit: 4221 6700NSW Health: www.health.nsw.gov.auSource: NSW Public Health; Professor Raina MacIntyre, University of NSW