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What is Swine flu is caused most commonly by and explain in detail?
Ans. is 'a' i.e., HiNi Swine flu Swine flu, also called swine influenza, or pig influenza, is caused by influenza virus. It is mainly occurs in swines (pigs) and occasionally transmitted to human. It is usually caused by influenza virus type A (Hi-NI). Incubation period is about 1-3 days and the symptoms of swine flu in humans are similar to most influenza infections, e.g. fever, cough, rhinorrhea, fatigue and headache. Other influenza virus causing swine flu, occasionally, are H,N2, H2N,, 1-13N2 and H2N3