Dear Doctor,

What exactly causes measles? Can it affect adults as well or it only catches children? Is it true that when one had had a measles attack it cannot reoccur? Jeanette

Dear Jeanette,

Measles is a highly contagious infection caused by the measles virus. It occurs due to droplet infection. An infected person can expel virus in the environment by coughing, sneezing or talking. Another person in close vicinity can inhale the virus. Occurrence and severity of the disease depends on the load of virus inhaled and immunity of the individual. The illness usually develops 10 to 12 days after exposure to an infected person and lasts from 7 to 10 days.

Initially there is high fever, cough, running nose and red eyes. Two to three days after, small white spots appear inside the mouth. This is followed by flat red rashes which spread all over the body. Complications can occur in form of diarrhoea, blindness, pneumonia, inflammation of the brain.

Measles can occur in adults as well, if not vaccinated as a child and living in crowded conditions. Adults suffer more severe symptoms as compared to children. Those with reduced immunity are more prone to it. It is true that once somebody has had measles, he will not get it a second time.

The diagnosis is fairly easy clinically. Confirmation can be done by tests for the virus and culture. There is no specific treatment. Antipyretic drugs like paracetamol are used to control the high fever. Adequate hydration is useful.

Measles vaccination is part of childhood vaccination programme and has reduced the prevalence of measles. An adult exposed to measles and if not vaccinated can take immunoglobulin injection to prevent development of the disease. A person with measles should avoid going out, because it remains contagious from approximately four days before to four days after, development of the rash.