Fact Sheet
Avian Influenza
What is Avian Influenza? Avian influenza or “bird flu” is an infectious disease of birds caused by type A strains of the influenza virus. Chickens, ducks and turkeys are very susceptible to epidemics of rapidly fatal influenza. Avian Influenza concerns It is uncommon for strains of influenza virus that infect birds to also infect humans. In recent years there have been a number of episodes when this has happened such as Hong Kong in 1997. The H5N1 bird flu strain is now widespread in many countries. In the vast majority of human cases of avian influenza to date, the human disease has been acquired directly from birds. The greatest concern regarding avian influenza is whether the virus will undergo a genetic change (i.e. mutation or adaptation) which would then allow human to human spread. If this occurs, a new worldwide pandemic is possible. What are the symptoms of avian influenza? Initial symptoms of high fever (often a temperature of more than 38°c) and flu like illness with a cough and lower respiratory tract symptoms have been common in most patients. Almost all patients have pneumonia. Diarrhoea, vomiting, abdominal and pleuritic pain, pain and bleeding from the nose and gums have also been reported in the early stages of the illness. Watery diarrhoea without blood appears to be more common in H5N1 avian influenza than in normal seasonal influenza. Incubation period The incubation period of avian influenza may be longer than other human influenzas. Most cases have occurred between 2 – 4 days but it can range up to 8 days or more. Infection Control March 2006
How is Avian Flu transmitted? Transmission of avian influenza from birds to humans requires direct contact with infected birds. The respiratory secretions and faeces of infected birds contain the virus. Preparation of birds for consumption and undercooked poultry may also be a source of infection. Human to human transmission of influenza virus is usually through the inhalation of infectious droplets or through contact with body surfaces or objects that have been contaminated with infected respiratory secretions. Prevention Prevention includes avoidance of sick birds and their faeces, strict personal hygiene and consideration of preventative antiviral therapy if exposed. Vaccines There is no vaccine currently available with proven efficacy against avian influenza. Researchers are currently studying possible new vaccines. Is there treatment available? There are antiviral drugs that have been successfully used in the treatment of influenza A virus. These may also be effective with avian influenza however there are limited supplies of these medications. Australia There are no current reports of Avian Influenza in birds or humans in Australia. The Australian government and other overseas agencies are closely monitoring the situation in SE Asia and worldwide. In the event that avian influenza should spread from person to person, the Australian Action Plan for Pandemic Influenza will be activated. For more information contact – The Infection Control Department on ext.5740 between 8.00 – 4.30 Monday to Friday. References and other Resources Center for Disease Control- www.cdc.gov Department of Human Services -www.health.gov.au World Health Organisation http://www.who.int/en/ Infection Control Website-www.rch.org.au/infection_control/index.cfm The New England Journal of Medicine 353;13 September 29, 2005
Infection Control March 2006