Number of U.S. Measles Cases Highest in More Than 25 years

Healthcare providers are urged to vaccinate patients and report all suspected cases of the highly contagious illness to public health authorities.

The United States is experiencing the highest number of reported measles cases since the contagious and potentially fatal viral illness was declared eliminated in in the country in 2000, federal statistics show.

Measles is a highly contagious condition that causes fever and rash, with complications including diarrhea, ear infections, pneumonia, encephalitis, premature birth, and rarely death, according to the New York City Department of Health and Mental Hygiene.

According to the latest statistics from the U.S. Centers for Disease Control and Prevention, there have been 1,250 measles cases this year through Oct. 3. The number of cases has already exceeded the highest number of annual cases reported in the past 25 years. The next highest number of cases in that span of time was reported in 1994, when there were 963 cases reported. The last time there was more than 1,250 cases was 1992.

A journal article published this month in Annals of Emergency Medicine provides a snapshot of U.S. measles cases from Jan. 1 to April 26. The article features several key data points:

• There were 704 reported measles cases
   
• 71% of the cases affected people who had not received the measles, mumps, and rubella (MMR) vaccine
   
• Thirteen outbreaks were reported in the country, accounting for 94% of reported cases. Six of the 13 outbreaks occurred in under-immunized, close-knit communities, accounting for 88% of all cases.
   
• Children and young people were the most affected population, with individuals age 4 and under accounting for nearly half of all cases. Individuals age 5 to 19 accounted for 29% of the cases. Only 4% of the cases were reported in people 50 or older.
   
• New York was a hotspot for measles cases, accounting for 67% of reported cases.
   
• Infection acquired in foreign countries was a significant factor in the measles cases, with 44 cases directly imported from abroad. Thirty-four of those cases were U.S. residents who had traveled overseas. The Philippines led source countries, with 14 cases. The other source countries linked to more than one U.S. case were Germany, Israel, Thailand, Ukraine, and Vietnam.

"High two-dose measles vaccination coverage in the United States has been critical to limiting transmission. However, increased global measles activity poses a risk to U.S. elimination, particularly when unvaccinated travelers acquire measles abroad and return to communities with low vaccination rates," the Annals of Emergency Medicine article says.

Healthcare provider guidance
 

The journal article offers the following guidance for clinicians to help address new measles cases and outbreaks:

• Unless there are contraindications to administering the MMR vaccine or evidence of immunity to measles, Americans traveling overseas should be vaccinated. Evidence of immunity includes written documentation of age-appropriate vaccination and laboratory confirmation of immunity.
   
• Infants from 6 to 11 months old should get one dose of MMR vaccine.
   
• Infants given MMR vaccine before their first birthday should get two more doses—one dose at 12 to 15 months old, and an additional dose at least a month after the first dose.
   
• All suspected cases of measles should be reported to public health authorities. 

Vaccination is essential to stop measles infections, the journal article says. "Recent outbreaks have been driven by misinformation about measles and MMR vaccine, which has led to under-vaccination in vulnerable communities."