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A boy with measles

Measles is making a comeback in California and nationally, and that has state public health officials concerned. They are urging anyone who hasn’t been vaccinated to do it now.

While the numbers seem small—13 cases were reported for this year to date, seven of those cases were reported since April. And 2010’s total of 27 measles cases compares to just nine for 2009.

The 13 cases this year were scattered around the state. In the Bay Area, there were two in Santa Clara County and one each in Alameda, Sonoma and San Mateo counties. The infected patients were all hospitalized.

Measles is a highly contagious virus that affects the respiratory system. It causes a red, skin rash, fever and cough and can lead to more serious problems, like pneumonia or encephalitis, if it worsens. A person who has measles is contagious to others for the four days before and after a rash appears. The virus is usually transmitted through coughing.

Nearly all of the people who were diagnosed with measles in the U.S. had traveled to countries with measles outbreaks or had contact with travelers who had been there. France, for example, has had 9,000 cases of measles in the last six months, so travelers to and from there are at risk of exposure. Several Asian and African nations are also in the midst of measles outbreaks, and they are considered possible sources of contagion for travelers coming into the United States. 

If you’ve had the MMR vaccine—measles, mumps and rubella, you are immune to infection. Parents of babies and young children should ensure that they are up to date on immunizations.

For parents worried about vaccinating their children, public health officials stress that the MMR vaccine is safe. Declining rates of vaccination for childhood illnesses, like whooping cough, have been blamed for the resurgence of that serious illness in the past few years. Whooping cough, also called pertussis, has reached epidemic levels in California and prompted officials to require all public school students--not just kindergarteners--to show proof of vaccination for the coming school year.