Complications of measles

Since it is not a brief answer, rather than respond to Mr. Bachtell's question in the comments, I'll do a front page post on it. CDC provides information about complications of measles here. This applies to the United States and other wealthy countries. Measles is much more dangerous in poor countries where many children are malnourished or debilitated from chronic infections, but that's a bit off topic.

The actual death rate from measles in developed countries is about 1-2 per 1,000. However, 1 in 20 children will get pneumonia as a complication, which may require expensive treatment including mechanical ventilation. An additional 1 child in 1,000 will develop encephalitis which may lead to permanent brain damage. A rarer complication is subacute sclerosing panencephalitis which develops several years after a measles infection. It is a progressive, disabling, fatal brain disorder which occurs in something like 4-11 out of 100,000 cases of measles but may be more common in children under 2 years of age.

The National Health Service lists additional complications including damage to vision and hepatitis. Measles in pregnant women increases risk of miscarriage, stillbirth, and premature delivery. We have not had the experience of a widespread measles epidemic in the present era in which there are more immunocompromised people in the population due to modern treatment of autoimmune disorders, transplant surgery, and HIV. These vulnerable people are at particular risk from those who refuse vaccination.

Most people recover from measles. It's usually a very unpleasant but self-limiting condition. Of course this results in school absenteeism, caregiver burden, and medical expenses. Serious complications are uncommon but can be very bad indeed. Given that vaccination has negligible risk and cost, there is a strong case to be made that it constitutes a social obligation, in my view.