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What is What is the period of infectivity in measles? and explain in detail?
<p>MEASLES:- An acute highly infectious disease of childhood caused by a specific virus of group myxovirus. Clinically characterised by fever and catarrhal symptoms of the upper respiratory tract( coryza,cough), followed by a typical rash. When the disease is introduced into a virgin community,more than 90% of population will be affected. Communicability- 4 days before the appearance of rash to 4 days after. Incubation period-10 days from exposure to onset of fever and 14 days of appearance of rash. Secondary attack rate-infection confers life long immunity as there is only one antigenic type. Vaccine- live attenuated subcutaneous vaccine. {Reference: park&;s textbook of preventive and social medicine, 23rd edition, pg no.149}</p>