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What is True about epidemology of influenza - and explain in detail?
Influenza is an acute respiratory tract infection characterised by sudden onset of chills,malaise,fever,muscular pain anx cough. Influenza A strains are pandemic.Incubation period 18 to 72 hours Major reservoirs exists in animals and birds Reference; Park&;s Textbook of preventive and social medicine, 24th edition.Pg no. 163,164