Pertussis has risen to 55 cases on Whidbey Island as of Monday morning, as opposed to the 43 cases earlier last week. All except two of these cases are children, mostly in the 7- to 11-year-old age group, according to Roger Case, M.D., Island County’s Health Officer.

Pertussis is also known as whooping cough. It is a highly contagious bacterial infection that causes violent fits of coughing leading to vomiting and trouble breathing.

Whidbey Island school districts allow students not to receive immunizations for personal or religious reasons. The Island County Health Department noted a trend between number of pertussis cases and pertussis immunization noncompliance rates among school districts.

All but seven cases of pertussis are from South Whidbey and Coupeville. South Whidbey harbors the majority of the pertussis cases and has a 12.4 percent immunization noncompliance rate in the school district. Coupeville School District has a 5.3 percent noncompliance rate. Oak Harbor School District has a 3.7 percent noncompliance rate.

The Island County Health Department is currently studying the immunization status of infected patients.

This is the second large pertussis outbreak of the year, according to Michele Roberts of the immunization program at the Washington State Department of Health. The other outbreak occurred in January in San Juan County.

Outbreaks like this illustrate the need for everyone to stay current on all types of vaccinations, according to Roberts. The pertussis vaccine is safe and usually causes few side effects.

Some people worry about how the vaccines are created in regards to fetal cells and testing. While some cell lines the vaccine is grown in do contain fetal cells, those cells are not contained in the vaccine, said Roberts.

“There’s some fact based in the use of aborted fetal cells, but it’s also become sort of an urban legend,” Roberts said.

The vaccine is tested for “years and years” before it’s used on the public, Roberts said. There are three phases of clinical trials that study safety and how the vaccine works in a population. These trials include thousands of people. After the trials, the vaccine can be licensed by the FDA. Then ongoing trials regarding effectiveness and safety are performed, explained Roberts.

The pertussis vaccine is not FDA licensed for people over the age of 64 because safety data is not known about that age group.

For people above age 64, Roberts recommended that they “make sure friends and family and caretakers are vaccinated.” Also, they should refrain from spending time in crowded areas or around people coughing.

Most cases of pertussis are occurring in areas where non-vaccination rates are high.

“Make sure your vaccines are up to date and look for credible sources to base your decisions off of,” said Roberts.

For more information about how the pertussis vaccine is made and tested, visit the Vaccine Education Center at the Children’s Hospital of Philadelphia Web site at www.chop.edu.

Vaccinations can be received at any healthcare provider. They are also available at the Family Resource Center in Oak Harbor on Mondays from 1 to 4 p.m. or Community Health Services on South Whidbey first and third Tuesdays from 1 to 4 p.m., no appointment necessary. For more information, call the Health Department at 679-7351.