Public health The once eradicated disease is on the upswing again due to declining childhood vaccination rates
Oregon is one of 13 states reporting a measles outbreak this year.
The Centers for Disease Control says it has been notified of 129 cases nationwide since January. Between 2001 and 2010, the U.S. saw on average fewer than 100 cases per year.
That number has risen in the past several years, due, epidemiologists say, to declining childhood vaccination rates.
Dr. Paul Cieslak is the medical director for the Oregon Health Authoritys immunization program. Cieslak says he typically sees up to three cases of measles in a year, but in 2014, hes already documented five cases in Oregon.
The virus infected a Multnomah County infant too young to receive the measles vaccine, and four members of a family in Marion County family that had not been vaccinated. The infant had recently traveled overseas.
Cieslak says measles has been more or less eradicated from the United States and that outbreaks in this country are generally triggered by travelers who bring the virus back from countries in Europe, Asia and Africa, where the disease is less well controlled.
The CDC says many of the current cases in the United States are linked to a major outbreak in the Philippines.
Once they get imported, you can see transmission for several generations of cases until finally the virus runs out of susceptible people to infect, Cieslak said. Our goal is to keep vaccination rates high enough so that happens sooner rather than later.
Cieslak says about 94 percent of kindergarteners statewide have received the full two-shot vaccine, although Oregon schools have the highest rate of non-medical vaccine exemptions in the country.
Cieslak says measles spreads rapidly through unvaccinated populations and is one of the most highly contagious diseases known, because it can be transmitted indirectly through the air.
With an airborne spread, you can cough into the air, and when a person walks into that room an hour later, they can get it. Its just a more highly contagious way of transmitting a disease, he said.
According to the Centers for Disease Control, measles causes fever, runny nose, cough and a rash all over the body.
About one in 20 children infected with the virus gets pneumonia. For every 1,000 children who get measles, one or two will die.
According to the World Health Organization, the measles virus killed about 122,000 people in 2012, mainly children under the age of 5.