Analysis of patients with swine flu in Australia, Canada, Mexico and New Zealand showsthat relatively healthy teenagers and young adults are among the vulnerable and resistant to the infection of H1N1 influenzapattern similar pattern was detected in 1918 when a similar influenza pandemic.Almost all critically ill patients during examination it was discovered that they were sick still a few daysbefore the onset of progressive symptoms of the viass,moreserious symptoms and respiratory failure,that requires treatment.The mortality rate ranges from 14.3% to 41.4%, depending on the country. Results of mass screening can help shed some light on what the consequences may occur after disease flu H1N1 and its treatment,"These studies tell us that young people are at risk for complications of H1N1 and under normal conditions, [seasonal] flu does not cause acute respiratory failure in young people,"Scientists have analyzed the cases in Australia and New Zealand, surveyed people who have severe acute respiratory disease (a condition in which the lungs fill with fluid)and were made to the life-support system known as extracorporeal membrane chamber. It is a system of artificial hearts and artificial light system, which delivers oxygen in the blood, and then delivers this blood to the tissues of the body, considered to be risky and expensive, as a result, it is not always available in every hospital. The mortality rate was 21% for such sick , although this figure may be higher, without treatment, researchers say"These studies provide important signals about how, with what doctors and hospitals may face in the coming months. All young, healthy patients who are infected or affected by the viass H1N1 can get respiratory failure, which may not always be cured by simple means to treat the flu, Although such patients are not currently a priority group for vaccination H1N1 .