State public health officials on Friday reported 15 confirmed cases of measles so far this year, prompting the state health department to urge all Californians to get a measles shot if they haven't already - especially if they’re planning on traveling to parts of the world where the disease is prevalent.
"Immunization is the best defense against measles, with 99 percent of persons developing immunity after two doses," Dr. Ron Chapman, director of the California Department of Public Health (CDPH), said in a statement. "With an outbreak in the Philippines and measles transmission ongoing in many parts of the world outside of North and South America, we can expect to see more imported cases of this vaccine-preventable disease."
So far, six California counties have reported measles cases: Los Angeles County (5), Orange County (3), Riverside County (3), Contra Costa County (2), Alameda County (1), and San Mateo County (1). Last year at this time, only two cases had been reported statewide.
Three of those afflicted with the respiratory virus this year had traveled to the Philippines, while two others had been to India, where measles is endemic, said the CDPH.
The state has been able to confirm that seven of the 15 victims were not vaccinated; it is unsure whether the other eight had gotten the vaccine, said CDPH spokeswoman Norma Arceo. All seven of the known unvaccinated people were "intentionally not vaccinated," said state epidemiologist Dr. Gil Chavez . "We can expect to see many more of imported cases of this vaccine-preventable disease, followed by local transmission, unless people take precautionary measures," he added.
California allows parents to opt out of vaccinating their children by invoking a personal belief exemption.
The seven measles patients who were known to have opted out of vaccinations were between seven and 32 years of age, said Kathleen Harriman of the CDPH.
"They were all minors other than two young adults," Harriman said. "And the young adults, it was their parents' decision, obviously, not to have them vaccinated when they were children."
After the introduction of the measles vaccination in the early 1960s, the incidence of measles in California dropped from a high of 39,000 cases reported annually to a record low of four cases in 2005, Chavez said.
Only about one percent of those who get two doses of the measles vaccine - the initial dose and the recommended booster - remain susceptible to the respiratory illness, Harriman said, adding that about 95 percent are immune after one vaccine dose.
Symptoms of a typical measles case usually starts with a mild to moderate fever, cough, runny nose, red eyes and sore throat, which is often followed several days later by tiny white spots inside the mouth and a red or brown rash on the body that starts in the face and upper neck and moves to the trunk and extremities, according to health officials.
About one third of cases develop complications that can lead to death, Chavez said. Those infected remain contagious for about eight days, four days before the onset of symptoms and four days after.
Infants, pregnant women and those with compromised immune systems are most susceptible to complications from the virus.