This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Communicable diseases, Subject name: Social & Preventive Medicine
True about measles is all except 
Select and explain. 
A. Kopliks spots appear as rash disappears, B. It is prevented by both active and passive immunization, C. Otitis media and meningitis are the most common complications, D. TB is aggravated in post measles
A: Kopliks spots appear as rash disappears
Answer: A: Kopliks spots appear as rash disappears 
Explanation: Measles (Rubeola): Incubation period: 10-14 days. Causative agent: RNA Paramyxovirus (so for only one serotype known) Source of infection: Cases (Carriers are not known to occur) Period of communicability: 4 days before and 5 days after the appearance of the rash. (Rash is retroauricular in origin) Measles has no second attacks (life long immunity is seen) Secondary attack rate of measle is 80% Measles shows a cyclical trend: Increases every 2-3 years. Blood cell type predominantly infected in Measles: Monocyte. Pathognomic clinical feature: Koplik spots (on buccal mucosa opposite Lower 2nd molar) Pathognomic microscopic feature: Wahin Finkedly cells (Multinucleated giant cells) MC complication of measles in young children: Otitis media. SSPE: Subacute sclerosing pan Encephalitis. Is a rare complication of measles: 1 per 10000-100000 cases of Measles (7-10 years after initial infection) Epidemic of measles occur: If propoion of susceptible children is > 40% If measles is introduced in a virgin community it infects >90% of children. Eradication of measles: Requires a vaccination coverage >96% Baby measles (Exanthem subitum-roseola infantum): Sixth disease (3 day fever) Ref: Park 25th edition Pgno: 159