Bird Flu and Swine Flu Infections

There are 3 types of influenza viruses - A, B and C. Only types A and B cause significant human disease. Influenza A is further sub-typed into 15 different H types (H1, H2, H3, etc) and 9 different N types (N1, N2, N3, etc). The past outbreak of Bird Flu in poultry which affected humans is caused by H5N1 subtype of Influenza A virus or we named it as A/H5N1 virus. Bird Flu spreads to humans mainly through contact with infected birds, which shed the virus in their saliva, nasal secretions and faeces. Very rarely, inefficient and limited human-to-human transmission “may” occur. Unlike Bird Flu, the current Swine Flu pandemic is caused by novel H1N1 subtype of Influenza A virus. It is contagious and spreading from human to human through coughing or sneezing by people with influenza. Sometimes people may become infected by touching something – such as a surface or object – with flu viruses on it and then touching their mouth or nose.
There is currently no vaccination to prevent against both Bird Flu and Swine Flu in humans. The available vaccination is for protection against human strains of the influenza virus. Two drugs, oseltamivir (commercially known as Tamiflu) and zanamivir (commercially known as Relenza) can reduce the severity and duration of illness caused by seasonal influenza. The efficacy of the two drugs depend on their administration within 48 hours after symptom onset. For cases of human infection with H5N1/H1N1, the drugs may improve prospects of survival, if administered early, but clinical data are limited. If there are no complications, most of the symptoms of influenza usually disappear after 6-7 days, although a cough may persist for over 2 weeks.