Three recent cases of whooping cough in Oak Harbor schools and one in Coupeville — as well as the measles outbreak in surrounding counties — should serve as a reminder of the importance of vaccinations, said Brad Thomas, the Island County Health Officer.

Coupeville schools sent out a letter to parents this week, notifying them that a student in the middle/high school was diagnosed with pertussis, commonly known as whooping cough.

Thomas said three students in Oak Harbor schools were diagnosed previously — two this month and one in March.

Since whooping cough is highly contagious, the students’ family members also had to be treated.

“It’s easy to treat and, unfortunately, easy to catch,” he said. “All told, 20 people were treated with antibiotics.”

All of the students who came down with whooping cough were vaccinated; Thomas said it’s a somewhat weak vaccine and a certain number of people who are exposed will contract it.

Still, he said, it’s important for people to get vaccinated to prevent the spread. Whidbey Island experienced an outbreak in 2008, which disrupted schools and extracurricular activities.

Pertussis, a bacterial infection, can be fatal for infants, Thomas said.

The illness causes violent fits of coughing; Thomas said they can be severe enough to cause people to vomit or even break ribs. The mild to severe cough can persist for as long as a couple of months.

Thomas stressed that adults need to get a booster shot. The immunization protocol calls for people to get five doses of the vaccine before age 7, followed by a booster at age 11 or 12 and another in adulthood.

As for measles, contraction of the illness can be totally prevented by vaccination, Thomas noted.

Measles is a highly contagious disease caused by a virus. It starts with a fever and leads to a cough, runny nose and red eyes. Then a rash of tiny, red spots breaks out, starting at the head and spreading to the rest of the body. Measles can be serious for young children; it can lead to pneumonia, encephalitis, swelling of the brain and even death, according to the Centers for Disease Control.

Thomas said measles has been reported in Skagit, San Juan, Whatcom and King counties, but not in Island County.

Measles cases are at the highest level in the U.S. in nearly 20 years; health experts believe it spread from the Philippines, where they are experiencing a very large outbreak, the CDC reported.