Rates of measles are usually fairly low in the United States.
Before the routine measles vaccination though, rates of measles cases were high. There used to be about 500,000 cases of measles and high rates of complications from those cases, including about 500 measles deaths each year in the United States.
After the last big measles outbreak in 1989 and the introduction of the MMR booster dose in 1994, cases of measles have dropped. In 2000, it was even declared that the endemic spread of measles in the United States had ended, and continued cases were all imported from outside the U.S.
Unfortunately, imported measles cases can still trigger small measles outbreaks in people who are at risk for measles, include those who are unvaccinated or under-vaccinated. This includes:
- infants who are too young to get their first dose of MMR
- toddlers and preschoolers who are too young to get their booster dose of MMR
- children who have a problem with their immune system, and so either can't get the MMR vaccine, or had the MMR vaccines but they don't work effectively because they are immunocompromised, such as children who are receiving chemotherapy for cancer
Most cases of measles are in children and adults who have simply not been vaccinated by choice though.
In 2011, there were more cases than any other year since 1996 (508 cases). We had at least 222 cases in 2011, passing the recent record set in 2008 (140 cases). While the incidence of measles in the US had dropped recently, with just 54 cases in 2012, there were at least 189 cases in 2013.
So far in 2014, there have already been over 112 cases of measles in the United States, including 32 in California alone and a large measles outbreak in New York City.
International Measles Outbreaks 2014
In addition to many developing countries where measles is still endemic, measles outbreaks have been reported internationally in:
- Netherlands - at least 2,499 cases in the Dutch "Bible belt" with at least one case of measles encephalitis and one death, a 17-year-old girl. Almost all of the measles cases in this outbreak are unvaccinated and the majority are children. An outbreak in Canada, with 42 cases, was linked to this outbreak in the Netherlands. A new outbreak in The Hague region has already gotten at least 15 people sick.
- Ukraine - 2,309 cases
- Russia - several large ongoing outbreaks in 2014
- Turkey - 7,132 cases (up from 700 last year) - CDC Watch Level 1 Travel Health Notice
- Georgia - more than 5,369 cases and 2 deaths
- France - 272 cases
- Ireland - 57 cases
- Austria - 75 cases in an ongoing outbreak
- Poland - 86 cases
- Italy - at least 2,216 cases with an outbreak in the Milan area (350 cases)
- Spain - 127 cases
- Germany - at least 1,772 cases (10 times more than 2012)
- Romania - 1,074 cases
- United Kingdom - 1,413 cases (2013), which follows 1,912 cases in 2012, the most since 1994, including a large outbreak in Wales and one death
- Australia - already 180 cases in 2014, (151 cases in 2013), including large clusters of cases in Victoria and Queensland.
- Vietnam - 108 deaths in children so far in 2014 (in just three large hospitals).
- New Zealand - 113 cases in 2014 (8 cases in 2013)
- Japan - 253 cases already in 2014 (232 cases in all of 2013), including at least one case of measles encephalitis and almost all unvaccinated or partially vaccinated.
- Canada - 40 cases in southern Alberta alone, 11 in Ontario, 10 in Saskatchewan, and at least 320 cases in an outbreak that began in a Christian school in British Columbia, but has now spread to the general community
- Philippines - at least 3,734 confirmed cases and an additional 9,568 reported cases in early January 2014 through February 24 and at least 23 deaths - CDC Watch Level 1 Travel Health Notice
- Indonesia - 6,300 confirmed cases - CDC Watch Level 1 Travel Health Notice
- Syria - at least 7,000 cases
- Pakistan - at least 290 children have died as over 30,000 people have gotten measles so far this year and their are daily reports of more children dying
- Southern Africa, including measles outbreaks in Lesotho, Malawi, Namibia, Mozambique, South Africa, Zambia, and Zimbabwe
- Eastern Africa, including measles outbreaks in Ethiopia and Kenya
High numbers of measles cases in Europe which began in 2010 continued in 2011, with more than 30,000 cases in each of those years. Overall, with more than 30,000 cases of measles in Europe in 2011, 8 deaths, 27 cases of measles encephalitis, and 1,482 cases of pneumonia, most cases were in unvaccinated (82%) or incompletely vaccinated (13%) people.
France was the hardest hit, with over 15,000 cases of measles and at least 6 deaths last year, 651 cases of severe pneumonia and 16 cases of encephalitis.
In 2013, Europe reported a milder measles season, with just 10,271 cases of measles, with most of the cases being found in Germany, Italy, Romania, the Netherlands and the United Kingdom. As in previous years, almost all cases were not vaccinated or were only partially vaccinated. These cases have been complicated by 8 cases of acute measles encephalitis and there have been 3 deaths.
The European Centre for Disease Prevention and Control also reports that like most countries in the developing world, measles is once again endemic in many parts of Europe "due to a decrease in the uptake of immunisation."
SSPE in Europe
A new development is the report in Germany of three cases of subacute sclerosing panencephalitis (SSPE), a rare, late complication of measles. On average, subacute sclerosing panencephalitis occurs about seven years after having a natural measles infection. The CDC reports that it causes a "progressive deterioration of behavior and intellect, followed by ataxia (awkwardness), myoclonic seizures, and eventually death."
Among the cases include:
- a six-year-old girl who had developed measles when she was seven-months-old and too young to get an MMR vaccine. Although she was only just diagnosed in October, she is already unable to walk and talk and has to be fed via a gastric tube.
- a 13-year-old girl who died in October. It is thought that she developed measles as an infant after being exposed to an unvaccinated 11-year-old boy at her doctor's office.
- a 19-year-old boy who developed measles when he was just 6-months-old from an unvaccinated child, SSPE when he was 10, and just died from complications of SSPE in February 2014.
Although there is no cure for SSPE, it is important to keep in mind that like measles, it can be prevented with the MMR vaccine.
A report on the "Epidemiology of Subacute Sclerosing Panencephalitis (SSPE) in Germany from 2003 to 2009: A Risk Estimation" that was published in PLoS ONE identified 31 children with SSPE and they found that "the risk of developing SSPE after acute measles infection below 5 years of age to be in the range of 1 in 1700 to 1 in 3300 cases of measles infection."
2008 Measles Outbreaks
Almost all cases of measles in the United States are linked to international travel. For example, of the 140 measles cases in 2008 in the U.S., 17 were initally linked to travel from Italy, Switzerland, Belgium, India, Israel, China, Germany, Pakistan, the Philippines, and Russia.
Of the 17 initial travelers who brought measles into the U.S. with them, 9 were US residents and 8 were visitors. This lead to measles cases in Illinois (32 cases), New York (27), Washington (19), Arizona (14), California (14), Wisconsin (seven), Hawaii (five), Michigan (four), Arkansas (two), and Washington DC, Georgia, Louisiana, Missouri, New Mexico, Pennsylvania, and Virginia (one each).
It is also important to note that:
- Only six of the patients (5%) had received two doses of MMR.
- Sixteen of the measles cases (13%) were in children who were too young to be vaccinated.
- One hundred and twelve of the cases (91%) were unvaccinated or had an unknown vaccination status.
- Sixty-three of the cases (66%) were in people who had a nonmedical vaccine exemption for vaccination.
And most importantly, according to the CDC, "the measles outbreaks in 2008 illustrate the risk created by importation of disease into clusters of persons with low vaccination rates, both for the unvaccinated and those who come into contact with them."
Measles Outbreaks - What You Need To Know
Other things to know about measles and measles outbreaks include:
- From 2 to 5% of people do not respond to their first dose of measles vaccine, which is why a booster dose is recommended.
- More than 99% of people develop immunity to measles after two doses of a measles vaccine, like MMR.
- A booster dose of MMR was first recommended in 1990 (for four year olds), so many adults born before 1986 may not have had two doses of MMR.
- Measles is fatal in about 0.2% of cases.
- The measles virus is spread by respiratory droplets and can stay in an area for up to two hours after a person with measles symptoms has left.
- People with measles are contagious from four days before they develop the measles rash to four days after it goes away.
- Call your pediatrician if you think your child has measles (don't just show up at their office or in the ER), especially if he develops a high fever and/or rash during a local measles outbreak or after a trip out of the country.
Most importantly, parents should understand that a measles vaccine (MMR) is the best way to protect your child from measles, and is especially important if there is a measles outbreak in your area or if you are traveling to an area with high rates of measles.
CDC. Measles: Unprotected Story: 106 Degrees: A True Story. November 4, 2010. Accessed February 2011.
CDC. Outbreak of Measles --- San Diego, California, January--February 2008. MMWR. February 29, 2008 / 57(08);203-206
CDC. Update: Measles --- United States, January--July 2008. MMWR. August 22, 2008 / 57(33);893-896
European Centre for Disease Prevention and Control. Measles and rubella monitoring January-December 2013. 28 Feb 2014
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)