The Doctor Is In is an occasional series where JHU Press authors discuss the latest developments and news in health and medicine. Guest post by Athena Kourtis Measles is very rare in countries with high rates of vaccination. In the United States, as in some other areas, measles transmission is considered to have been interrupted through vaccination. There are still some cases of measles in the United States (about 50 per year), because visitors from other countries or U.S. citizens traveling abroad can become infected and spread the infection to unvaccinated or unprotected people. Measles has increased in recent years, and outbreaks have spread in Europe, the Centers for Disease Control and Prevention (CDC) recently reported. In 2011, measles outbreaks were reported in 36 European countries, with tens of thousands of cases. The largest number of cases was reported in France (14,000 cases), and predominantly affected older children and young adults who had not been vaccinated. Europe has become a major source of virus introduction to the United States. Lack of knowledge of the seriousness of the disease and fear of alleged adverse effects—often fueled by media coverage—contributes to lack of vaccination among susceptible individuals. The CDC recommends measles vaccination for all children at the age of 12-15 months and a second dose at 4-6 years. Two doses of the vaccine provide a high degree of protection against this disease, which can be serious and even fatal. About 1 of every 1,000 children with measles get encephalitis and 1 or 2 out of 1,000 children with measles die. Dr. Athena Kourtis is a pediatrician and an infectious diseases specialist and author of the book Keeping Your Child Healthy in a Germ-Filled World: A Guide for Parents, now available from the JHU Press. The information provided in this blog post is not meant to substitute for medical advice or care provided by a physician, and testing and treatment should not be based solely on its contents. Instead, treatment must be developed in a dialogue between the individual and his or her physician. This post has been written to help with that dialogue. The services of a competent medical professional should be obtained whenever medical advice is needed.