Measles is a highly contagious viral illness that has fortunately been fairly well-controlled through measles vaccination plans.
Before routine use of the measles vaccine, there were about 500,000 cases of measles in the United States each year and about 500 deaths. Measles also led to about 48,000 people being hospitalized and another 1,000 people being left with chronic disability from measles encephalitis.
Since 2006, measles cases in the U.S. have ranged from a low of 43 (2007) to a high of 140 (2008). That was of course until this year, when we set a new record, with at least 220 cases so far this year.
Many experts think that there may actually have been many more measles cases each year than the 500,000 reported -- maybe as high as 3 to 4 million each year.
One thing is clear, though -- measles cases in the U.S. declined by 98% following the measles vaccination program that started in 1963. This first inactivated, or killed, measles vaccine was soon replaced by a more effective attenuated live measles vaccine in 1967.
In 1971, the measles vaccine was combined with the vaccines for mumps and rubella, and is given as a single, combination MMR vaccine. At that time, measles vaccination only called for one dose of vaccine, unlike the two-dose schedule that is used today.
Although effective, measles vaccination with only one dose provides just 95% protection against measles. A second, booster dose helps to improve the effectiveness of the measles vaccine to over 99%.
A booster dose of MMR was not recommended until 1990.
Worldwide, measles vaccination through the Measles Initiative has led to a 78% reduction in measles deaths, from about 733,000 deaths in 2000 to 164,000 in 2008. A resurgence in measles cases in 2009 and 2010 may mean that measles deaths are going to be up again, however.
Measles Vaccination Alert
The routine measles vaccination plan calls for kids to get the first MMR vaccine when they are 12 to 15 months old and the MMR booster when they are 4 to 6 years old.
Because of the rise in worldwide measles cases and an increase in measles cases among travelers returning from trips out of the U.S., some new measles vaccination recommendations now include that:
- Infants aged 6 to 11 months should receive 1 dose of MMR vaccine before they travel out of the country.
- Children who are at least 12 months old who are traveling internationally should receive 2 doses of MMR vaccine, separated by at least 28 days. This means that many toddlers and preschoolers would need to get their booster dose of MMR early, before they are 4 to 6 years old.
Keep in mind that any dose of MMR given before your child's first birthday won't count towards the 2 doses of MMR needed as a part of routine measles vaccination. Although it is thought to provide some protection against measles, the effectiveness of the MMR vaccine can vary if it is given before a toddler is 12 months old, and is best repeated to make sure a child is fully protected against measles.
Measles Vaccination for Adults
Parents who are keeping up with the latest measles outbreaks have likely observed that it isn't just unvaccinated kids who are getting measles.
Adults who are unvaccinated against measles, or more likely, are not fully vaccinated, have frequently contracted measles while traveling out of the U.S. and started outbreaks back home too.
Just like kids, adults born in or after 1957 should receive two doses of MMR if they are exposed to measles or are going to travel out of the U.S. People born before 1957 are thought to be immune to measles.
Since the measles vaccination plan to get kids booster doses of MMR didn't become routine until 1990, it is thought that many adults born before 1986 may not be fully vaccinated and protected against measles. Adults who were born after 1986 would likely have had the booster dose of MMR at their 4 year old checkup.
Also, adults may need to:
- Consider being revaccinated with 2 doses of MMR if they were vaccinated with the original inactivated measles vaccines from 1963 to 1967.
- Get a second dose of MMR if they are going to be a student in a postsecondary educational institution or work in a health-care facility.
Remember, measles vaccination is a safe and effective way to avoid measles and prevent further measles outbreaks.
CDC. Measles Imported by Returning U.S. Travelers Aged 6-23 Months, 2001-2011. MMWR. April 8, 2011 / 60(13);397-400.
CDC. Measles Outbreaks and Progress Toward Measles Preelimination -- African Region, 2009-2010. MMWR. April 1, 2011 / 60(12);374-378.
World Heath Organization. Measles Fact Sheet. December 2009. Accessed April 2011.