Child getting a shot in the shoulder

The U.S. reported 170 cases of measles in 17 states and the District of Columbia by the end of February. Most of the cases of measles are in California and are linked to Disneyland. If that pace continues, it would break last year's record 644 cases, by far the most in 15 years. That trend concerns public health officials because in many states, like Oregon and Idaho, vaccination rates have dropped in recent years.

A recent Centers for Disease Control and Prevention (CDC) survey estimated the rate of measles vaccination of kindergartners in the 2013–14 school year is:

  • Idaho: 88 percent
  • Oregon: 93.2 percent
  • Washington state: 89.7 percent
  • Utah: 98.5 percent.

That means many children in Idaho, Oregon and Washington start school without protection from measles, one of the most contagious diseases known.

High vaccination rates form a herd immunity that helps protect people who are not vaccinated. However, when many people with a lower vaccination rate get together, outbreaks are much more likely to happen.

Officials are taking action to prevent public health risks. In California, some hospitals and doctors are keeping unvaccinated children from entering their facilities. Unvaccinated students are being sent home from some schools. 

Recognizing measles

Because the U.S. declared measles "eliminated" in 2000, many doctors have never seen or treated measles and may mistake the signs.

Here's what a case of measles looks like: You get an all-over rash, watery eyes that may be sensitive to light, a cough and a high fever. About three out of 10 people get complications, such as pneumonia, ear infections or diarrhea.

Measles rarely kills those who can get good health care quickly.  Worldwide, however, measles killed about 145,000 last year among people who are without health care. 

What you can do

The good news is that the measles vaccine is 95 percent effective. The CDC recommends children receive an initial dose of the measles-mumps-rubella (MMR) vaccine at 12 to 15 months of age. They should get a booster shot at four to six years of age. Nearly everyone is protected for more than 20 years after the second MMR vaccination.

If you (as an adult) cannot remember being vaccinated (or revaccinated), you can also ask to be vaccinated. Repeating it won't hurt you.

Published Feb. 6, 2015.