From January 1 to January 28, 2015, 84 people from 14 states were reported to have measles*. Most of these cases are part of a large, ongoing outbreak linked to an amusement park in California.
On January 23, 2015, CDC issued a Health Advisory to notify public health departments and healthcare facilities about this multi-state outbreak and to provide guidance for healthcare providers nationwide.
* CDC will update this data weekly on Mondays.
The United States experienced a record number of measles cases during 2014, with 644 cases from 27 states reported to CDC's National Center for Immunization and Respiratory Diseases (NCIRD). This is the greatest number of cases since measles elimination was documented in the U.S. in 2000.
Outbreaks in countries to which Americans often travel can directly contribute to an increase in measles cases in the U.S.
Reasons for an increase in cases some years:
- 2015: The majority of cases reported so far during 2015 are part of a large, ongoing outbreak linked to an amusement park in California.
- 2014: The Philippines is experiencing a large, ongoing measles outbreak. Many of the cases in the U.S. in 2014 were associated with cases brought in from the Philippines. For more information see the Measles in the Philippines Travelers' Health Notice.
- 2013: The U.S. experienced 11 outbreaks in 2013, three of which had more than 20 cases, including an outbreak with 58 cases. For more information see Measles — United States, January 1-August 24, 2013.
- 2011: In 2011, more than 30 countries in the WHO European Region reported an increase in measles, and France was experiencing a large outbreak. Most of the cases that were brought to the U.S. in 2011 came from France. For more information see Measles — United States, January-May 20, 2011.
- 2008: The increase in cases in 2008 was the result of spread in communities with groups of un-vaccinated people. The U.S. experienced several outbreaks in 2008 including three large outbreaks. For more information see Update: Measles — United States, January–July 2008.
See also: The Surveillance Manual chapter on measles that describes case investigation, outbreak investigation, and outbreak control for additional information.
Measles can be prevented with the MMR (measles, mumps, and rubella) vaccine. In the United States, widespread use of the measles vaccine has led to a greater than 99% reduction in measles cases compared with the pre-vaccine era. From 2000 to 2013, a range of 37 to 220 measles cases per year were reported in the United States, and most of these originated outside the country.
Measles is still common in other countries. The virus is highly contagious and can spread rapidly in areas where people are not vaccinated. Worldwide, an estimated 20 million people get measles and 122,000 people die from the disease each year—that equals about 330 deaths every day or about 14 deaths every hour.
Evidence of Immunity
Acceptable presumptive evidence of immunity against measles includes at least one of the following:
- written documentation of adequate vaccination:
- one or more doses of a measles-containing vaccine administered on or after the first birthday for preschool-age children and adults not at high risk
- two doses of measles-containing vaccine for school-age children and adults at high risk, including college students, healthcare personnel, and international travelers
- laboratory evidence of immunity
- laboratory confirmation of measles
- birth in the United States before 1957
Healthcare providers should not accept verbal reports of vaccination without written documentation as presumptive evidence of immunity. For additional details about evidence of immunity criteria, see Table 3 in Prevention of Measles, Rubella, Congenital Rubella Syndrome, and Mumps, 2013: Summary Recommendations of the Advisory Committee on Immunization Practices (ACIP)
CDC recommends all children get two doses of MMR vaccine, starting with the first dose at 12 through 15 months of age, and the second dose at 4 through 6 years of age. Children can receive the second dose earlier as long as it is at least 28 days after the first dose.
Adults who do not have evidence of immunity against measles should get at least one dose of MMR vaccine.
People 6 months of age and older who will be traveling internationally should be protected against measles. Before any international travel.
- Infants 6 through 11 months of age should receive one dose of MMR vaccine. Infants who get one dose of MMR vaccine before their first birthday should get two more doses (one dose at 12 through 15 months of age and another dose at least 28 days later).
- Children 12 months of age and older should receive two doses of MMR vaccine, separated by at least 28 days.
- Teenagers and adults who do not have evidence of immunity against measles should get two doses of MMR vaccine separated by at least 28 days.
Healthcare personnel should have documented evidence of immunity against measles, according to the recommendations of the Advisory Committee on Immunization Practices [48 pages]. Healthcare personnel without evidence of immunity should get two doses of MMR vaccine, separated by at least 28 days.
For more information, see measles vaccination recommendations.
For Those Getting Vaccinated
Vaccination recommendations and other useful information about the measles vaccine:
- Measles Vaccine Basics
- Beliefs & Concerns
- Vaccine Safety
- Who Should Not be Vaccinated?
- Where to Get MMR Vaccine
Estimates of the number of people living in the U.S. who have received particular vaccines at the national, state, and local levels using results from the National Immunization Survey: