Before a vaccine was licensed in1963, there were an estimated 3 to 4 million cases of measles each year. In the years following 1963, the number of measles cases dropped dramatically, with only 1,497 cases in 1983, the lowest annual total reported up to that time.
From 1989 to 1991, 55,622 cases were reported with a total of 123 measles-associated deaths. Half of the cases and deaths were in young children. The most important cause of this epidemic was low immunization rates among preschool-age children. Due to increased immunization efforts after this epidemic, measles cases fell during the 1990s. Only 44 cases were reported in 2002. However, measles is still common in many other countries in the world and can easily be imported, so continued immunization against the disease is still important.
Most people receive measles vaccine as part of a combination vaccine known as M-M-R II® which also protects against two other viruses – mumps and rubella. Another option is a vaccine called Proquad® which provides protection against measles, mumps, rubella and varicella (chicken pox) in one shot. A vaccine protective against measles only is also available and called Attenuvax®. All three of these vaccines are produced by Merck and Co, Whitehouse Station, NJ.
Measles vaccines are live, attenuated (weakened) virus vaccines. This means that after injection, the virus grows, and causes a harmless infection in the person immunized. The body’s immune system fights the infection caused by the weakened virus, which results in the person becoming immune to measles infection.
Fever is the most common side effect, occurring in 5%-15% of vaccine recipients. About 5% of people develop a mild rash. When they occur, fever and rash appear 7-10 days after vaccination. About 25% of adult women receiving MMR vaccine develop temporary joint pain, although this symptom is related to the rubella component of the combined vaccine. Joint pain only occurs in women who are susceptible to rubella at the time of vaccination.
More severe reactions, including allergic reactions, are rare. About one person per million develops inflammation of the brain due to the measles component of the MMR vaccine.
Current scientific evidence does not support the hypothesis that measles-mumps-rubella (MMR) vaccine causes autism. The question about a possible link between MMR vaccine and autism has been extensively reviewed by independent groups of experts in the U.S. including the National Academy of Sciences' Institute of Medicine. These reviews have concluded that the available epidemiologic evidence does not support a causal link between MMR vaccine and autism.
The MMR-autism theory had its origins in research by Andrew Wakefield and colleagues in England. Those colleagues have retracted their article about the theory. Studies that suggest a cause-and-effect relationship between MMR vaccine and autism have received a lot of attention by the media. However, these studies have significant weaknesses and are far outweighed by many population studies that have consistently failed to show a causal relationship between MMR vaccine and autism. For a summary of the issues surrounding this topic, please read "Vaccines and Autism," by Paul A. Offit, MD, Director, Vaccine Education Center, Children's Hospital of Philadelphia. This article can be accessed online at: www.immunize.org/catg.d/p2065.htm. For more information and links to related journal articles, visit IAC's "Autism" page at: www.immunize.org/safety/autism.htm
This vaccine is a 0.5-mL dose shot given subcutaneously (in the fatty layer of tissue under the skin). Give children the first dose at 12 to 15 months of age and the second dose at 4 to 6 years of age. Give MMR to children who have not received the second dose by their 11- to 12-year-old visit. There should always be at least 4 weeks between the first and second dose.
ProQuad®, the quadruple vaccine, is indicated for children 12 months to 12 years of age if a second dose of measles, mumps, and rubella vaccine is to be administered.
Adults born before 1957 are assumed to be immune to measles by natural infection. Give adults born in 1957 or later, who do not have medical restrictions, at least one dose of MMR vaccine during their lifetime. Give two lifetime doses of MMR vaccine to certain adults born in 1957 or later including healthcare workers, those who travel overseas, or those who attend college, or post-secondary educational institutions. These adults should receive two doses of MMR or have other evidence of measles immunity (lab test or physician-diagnosed measles).
A second dose of MMR is also recommended for adults who have been recently exposed to measles or who are in an outbreak setting, were previously vaccinated with killed measles vaccine, were vaccinated with an unspecified measles vaccine between 1963 and 1967, or plan to travel internationally.
M-M-R II® is administered to military basic trainees, unless they have positive blood tests or documented evidence of two prior vaccinations. For other adults and children, DoD follows guidelines of the Advisory Committee on Immunization Practices (ACIP). In general, ACIP prefers use of M-M-R II® to monovalent (Attenuvax®) or bivalent vaccines, to optimize immunity to all three diseases.
The following people should not receive MMR vaccine:
In the past, it was believed that people who were allergic to eggs would be at risk of an allergic reaction from the vaccine because the vaccine is grown in tissue from chick embryos. However, recent studies have shown that this is not the case. Therefore, MMR may be given to egg-allergic individuals without prior testing or use of special precautions.
Some of these serious allergic reactions may be related to a severe allergy to gelatin. If you or a family member has a severe allergy to gelatin, tell your health care worker.
Severely immunocompromised people should not be given MMR vaccine. This includes people with conditions such as congenital immunodeficiency, AIDS, leukemia, lymphoma, generalized malignancy, and those receiving treatment for cancer with drugs, radiation, or large doses of corticosteroids. Household contacts of immunocompromised people should be vaccinated according to the recommended schedule. Although people with AIDS or HIV infection with signs of serious immunosuppression should not be given MMR, people with HIV infection without symptoms can and should be vaccinated against measles.
Women who are breast-feeding can be vaccinated. Children and other household contacts of pregnant women should be vaccinated according to the recommended schedule.