Influenza is RNA virus that causes seasonal epidemics. Severe disease is most common among the elderly, Young children and those with underlying illness. In 2009; virus emerged in North America and rapidly spread around the world. Initial outbreaks in Thai schools and military camps quickly lead to community. Influenza is thought to be spread by droplet and airborne transmission. Flu causes yearly epidemics of respiratory illness of varying severity worldwide in people of all ages, and it may be the most important cause of medically. Flu are the leading cause of death from infection and cause of death overall. Indirect contact via contaminated hands or inanimate objects may be important, especially where ill children interact with caregivers and siblings and can be cultured from surfaces at room temperature for up to 3 days. Washing has to effectively reduce influenza virus on hands