Incubation period of measles is: September 2011
Ans. B: 10 days For measles, time period from exposure and development of first symptom (onset of fever) is 10 days Measles/ Rubedegla/ Morbilli It is an infection of the respiratory system caused by a virus, specifically a paramyxovirus of the genus Morbillivirus. Morbilliviruses, like other paramyxoviruses, are enveloped, single-stranded, negative-sense RNA viruses. Symptoms include fever, cough, runny nose, red eyes and a generalized, maculopapular, erythematous rash. Measles (also sometimes known as English Measles) is spread through respiration (contact with fluids from an infected person's nose and mouth, either directly or through aerosol transmission), and is highly contagious -- 90% of people without immunity sharing living space with an infected person will catch it. An asymptomatic incubation period occurs nine to twelve days from initial exposure and infectivity lasts from two to four days prior, until two to five days following the onset of the rash (i.e. four to nine days infectivity in total). An alternative name for measles in English-speaking countries is rubeola, which is sometimes confused with rubella (German measles); the diseases are unrelated The classical symptoms of measles include four-day fevers and the three Cs -- cough, coryza (head cold) and conjunctivitis (red eyes). The fever may reach up to 40 degC (104 degF). Koplik's spots seen inside the mouth are pathognomonic (diagnostic) for measles, but are not often seen, even in real cases of measles, because they are transient and may disappear within a day of arising. The characteristic measles rash is classically described as a generalized, maculopapular, erythematous rash that begins several days after the fever stas. It stas on the head before spreading to cover most of the body, often causing itching. The rash is said to "stain", changing color from red to dark brown, before disappearing. The measles rash appears two to four days after initial symptoms, and lasts for up to eight days. Complications Complications with measles are relatively common, ranging from relatively mild and less serious diarrhea, to pneumonia, Otitis media and acute encephalitis (and rarely subacute sclerosing panencephalitis); corneal ulceration leading to corneal scarring. Complications are usually more severe in adults who catch the virus.
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