SACRAMENTO, Feb. 23 (UPI) -- Fifteen cases of measles since Jan. 1 are confirmed -- compared to two measles cases at this time last year, California health officials say.
Dr. Ron Chapman, state health officer and director of California Department of Public Health in Sacramento said the cases occurred throughout California.
"Immunization is the best defense against measles, with 99 percent of persons developing immunity after two doses," Chapman 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."
Imported cases can spread to the community, especially among unvaccinated persons, including infants too young to be vaccinated, Chapman said.
High immunization rates in California have kept preventable childhood diseases, such as measles, at record lows during the past 20 years.
In 2000, measles was declared eliminated in the United States, but the number of cases per year in California ranged from four to 40 cases due to infected visitors or unvaccinated Americans visiting countries where measles still occurs.
Among the California cases with measles onset in 2014, three traveled to the Philippines, where a large outbreak is occurring, and two traveled to India, where measles is endemic, Chapman said.
Measles is a highly contagious viral disease that is spread through the air when someone who is ill with the disease coughs or sneezes.
It is recommended children get their first dose of MMR -- measles, mumps, rubella -- vaccine at 12 to 15 months. The second dose of MMR is usually administered before children start kindergarten at ages 4 to 6. Immunized adults do not need boosters. However, anyone born since 1957 who has not had two doses of vaccine might still be vulnerable to measles and should ask their doctor about getting immunized.
Unvaccinated Californians who plan to travel outside of North or South America should receive the MMR vaccine before they go. Infants who are traveling can be vaccinated as young as six months of age -- although they should also have the two standard doses of MMR vaccine after their first birthday.
Some county health departments are reminding physicians to not delay reporting any cases of measles.