The rise in measles cases and increasing numbers of outbreaks likely has some parents wondering if their kids are at risk.
Most parents understand that measles is a vaccine preventable disease, but some may not be absolutely sure when their kids get fully protected against measles.
Measles vaccination is protective against measles, but measles is not just a disease in kids whose parents refuse or delay vaccines.
Measles Risk Factors
Some of the kids who get caught up in these measles outbreaks are unvaccinated because they are too young to be vaccinated.
Other children at risk for measles can include those that are:
- unvaccinated because they have a medical contraindication to getting the MMR (measles-mumps-rubella) vaccine, such as being immunocompromised, including children receiving cancer chemotherapy or high doses of steroids
- incompletely vaccinated because they haven't received their booster dose of MMR
- immunocompromised, even if they had previously received the MMR vaccine, including children receiving cancer chemotherapy
Since approximately 20% of measles cases require hospitalization, and even more go to the doctor or ER because of the high fever, that can put other kids in the ER and hospitalized kids with immune system problems at risk if they are not carefully separated. Unfortunately, when parents take their kids with measles to the emergency room or doctor for medical attention, they rarely suspect that they have measles, and so expose many people when they are most contagious.
Since children are normally vaccinated against measles with the MMR vaccine when they are 12 to 15 months (first dose) and again at 4 to 6 years (booster dose), that means that:
- infants are at risk for measles before they get their first MMR shot
- toddlers and preschoolers are still at risk for measles because they are only partially immune after they get their first MMR shot (until they get their booster dose)
Since measles vaccination with two doses of MMR is the best way to get that immunity, shouldn't kids get those shots as early as possible?
There are situations when it is recommended that children get their MMR shots earlier than the recommended CDC immunization schedule, especially for those kids who will be traveling out of the United States. For those children, the CDC states that the MMR vaccine can be given to infants as young as six months of age. Children who are at least 12 months old should get two doses of MMR, separated by at least 28 days.
If measles cases in the United States continue to rise, this could become a more general recommendation at some point. The CDC manual on measles outbreak control states that "If many cases are occurring among infants younger than 12 months of age, measles vaccination of infants as young as 6 months of age may be undertaken as an outbreak control measure."
Unfortunately, children who get the MMR shot before they are 12 months old will have to get it repeated when they are 12 months old, since early doses are thought to be less effective.
Of course, the best way to avoid measles is to have immunity to this highly contagious disease.
If your child is exposed to measles or if there is a measles outbreak in your area, you should:
- Double-check your child's vaccine records to make sure he has his age-appropriate doses of MMR.
- Get your child caught up on any missed vaccines, especially the MMR, which can provide some protection if your child is exposed to measles and has not been vaccinated yet -- as long as he gets an MMR shot within 72 hours of his exposure.
- Double-check your own vaccine records, as some adults may not have had an MMR booster if they were born before 1990, when getting a booster dose of MMR became routine.
- Also double-check your own vaccine records to see if you were vaccinated with the original inactivated measles vaccines from 1963 to 1967, which was not as effective as the newer MMR, and should be repeated.
- Be prepared for your child to be quarantined from school for up to 21 days if there is a measles outbreak and he is not vaccinated against measles and you don't want to get him a post-exposure dose of MMR vaccine.
Most importantly, don't plan any international travel if everyone in the family isn't up-to-date on their measles vaccines. Most of the current measles outbreaks start with a single unvaccinated person traveling out of the country to an area with high rates of measles. While that once meant traveling to third world or developing countries, there are now high rates of measles in many countries in Europe and other industrialized countries.
That makes it important to get properly vaccinated before traveling out of the country, no matter where your family plans to go.
CDC Health Information for International Travel 2010.
CDC. Measles Imported by Returning U.S. Travelers Aged 6--23 Months, 2001--2011. MMWR. April 8, 2011 / 60(13);397-400.
Manual for the Surveillance of Vaccine-Preventable Diseases (4th Edition, 2008)
The Pink Book: Epidemiology and Prevention of Vaccine Preventable Diseases. Updated 11th Edition, (May 2009)