I was brought up in the pre-vaccine era and pretty much everyone caught measles at some stage in their childhood or as a young adult. If you were one of the unlucky ones, the effects could be very nasty. I have used US data because theirs’ is more comprehensive. The basic effects and rates are the same for Australia. The Effects of Measles Measles is a serious disease caused by a highly contagious virus. It begins with fever followed by cough, runny nose and conjunctivitis. Infections of the middle ears, pneumonia, croup, and diarrhoea are common complications. Measles encephalitis (an infection of the brain) occurs in 1 per 1,000 cases of natural measles, frequently resulting in permanent brain damage in the survivors. Approximately 5% of children (500 out of 10,000) with measles will develop pneumonia. In addition, 1 to 3 of every 1,000 children who get measles in the United States dies from the disease. Vaccination and Measles The benefit of measles vaccination in preventing illness, disability, and death has been well documented. The first 20 years of licensed measles vaccination in the U.S. prevented an estimated 52 million cases of the disease, 17,400 cases of mental retardation, and 5,200 deaths. During 1999–2004, a strategy led by the World Health Organization and UNICEF led to improvements in measles vaccination coverage that averted an estimated 1.4 million measles deaths worldwide. Vaccination Side Effects In very rare cases (far less than 1 child out of 10,000 given MMR), children have a serious reaction, such as lowered consciousness, coma, or hypersensitivity (anaphylaxis)—swelling inside the mouth, difficulty breathing, low blood pressure, and rarely, shock. Even more rarely, children may have low blood platelets that can lead to a temporary bleeding problem that is described in more detail in the “Related Issues” section below. Since 1990, there have been 11 case reports of anaphylaxis in those who received the vaccine. Thirty to 40 million children were vaccinated during this time period. No children who experienced such a reaction died as a result.