Mumps Vaccination for Specific Groups

Students at post-high school educational institutions

Students at post-high school educational institutions who do not have presumptive evidence of immunity should receive 2 doses of MMR vaccine, each dose separated by at least 28 days.

International travelers

Persons aged 6 months and older who will be traveling internationally to any country outside the United States who do not have presumptive evidence of immunity should be vaccinated with mumps-containing vaccine if they are not already protected against measles, mumps, and rubella. Before any international travel—

• Infants 6 through 11 months of age should receive 1 dose of MMR vaccine. Infants who get 1 dose of MMR vaccine before their first birthday should get 2 more doses according to the routinely recommended schedule.
  • The first dose should be given at 12 through 15 months of age and the second dose at 4 through 6 years of age.
  • The second dose can be administered earlier as long as at least 28 days have elapsed since the first dose.
• Persons 12 months of age and older who will be traveling internationally should receive 2 doses of mumps-containing vaccine,A separated by at least 28 days; unless they have other presumptive evidence of immunity against mumps.

Healthcare personnel

Healthcare personnel without presumptive evidence of immunity should get 2 doses of MMR vaccine, separated by at least 28 days. Although birth before 1957 is considered acceptable evidence of immunity in routine circumstances, healthcare facilities should consider vaccinating healthcare personnel born before 1957 who lack laboratory evidence of immunity or laboratory confirmation of disease.

Groups at increased risk during mumps outbreak

After the U.S. mumps vaccination program started in 1967, there has been a more than 99% decrease in mumps cases in the United States. However, mumps outbreaks still occur, particularly in settings where people have close, prolonged contact, such as universities, schools, and correctional facilities.

In outbreaks of highly vaccinated communities, the proportion of cases that occur among vaccinated people may be high. This does not mean that the vaccine is ineffective. The effectiveness of the vaccine is assessed by comparing the attack rate in vaccinated people with the attack rate in unvaccinated people. During outbreaks, unvaccinated people usually have a much greater mumps attack rate than fully vaccinated people.

In October 2017, ACIP recommended that people identified by public health authorities as being part of a group at increased risk for acquiring mumps in an outbreak should receive a third dose of MMR vaccine. This recommendation aimed to improve protection of people in outbreak settings against mumps disease and mumps-related complications.

Vaccination during outbreaks

• Children 12 months of age to 4 years of age who are unvaccinated should receive 1 dose of MMR or MMRV.
• People 4 years of age or older who are unvaccinated or have received only 1 dose of MMR or MMRV should receive MMR.
  • 2 doses for unvaccinated
  • 1 dose for people who previously received the first dose (administered 28 days apart)
• You should not give a third dose unless your patient is part of a group at increased risk, determined by your local public health authorities. If you suspect an outbreak or are unsure if your patient belongs to a group at increased risk, contact your local health department for more information.

Mumps in vaccinated people

During outbreaks, people who previously had 1 or 2 doses of MMR vaccine can still get mumps and can still transmit the disease. Disease symptoms are generally milder, and complications are less frequent in vaccinated people.

Experts aren't sure why vaccinated people still get mumps, but some evidence suggests that:

• Some people's immune systems may not respond as well as they should to the vaccine.
• The mumps vaccine may produce antibodies (proteins created by the body's immune system to help fight infections) that are not as effective against wild-type, circulating mumps virus.
• In some people, antibodies from mumps vaccination may decrease overtime, until they no longer protect the person from mumps.
• As most people are not routinely exposed to mumps, there is less immunologic boosting (where people are exposed to mumps which boosts their immunity, but they do not get sick).