Infectious Diseases >> Avian Flu

What is it?

Avian Influenza viruses are normally highly species-specific. Of the hundreds of strains of avian influenza viruses, only four are known to have caused human infections: H5N1, H7N3, H7N7, and H9N2. Of all influenza viruses that circulate in birds, the H5N1 virus is of greatest concern for human health. The study by WHO from 2003 to Nov 2007, reveals, out of 334 laboratory confirmed cases from 12 different countries, 205 cases were fatal. Overall mortality in H5N1 cases is approximately 60%. The majority of cases have occurred among children and adults aged less than 40 years old. Mortality was highest in cases aged 10-19 years old.