Vaccine 'breakthrough' cases double in Washington, but still .01 percent of all vaccinations

The number of people infected with COVID-19 after being fully vaccinated has more than doubled in Washington, but health officials stress that breakthrough cases are expected with any vaccine.

According to the state Department of Health, there have been 217 COVID-19 vaccine breakthrough cases reported in Washington state as of April 3. That's up from 102 since DOH first reported breakthrough cases on March 30.

The state is investigating the deaths of five people who died of COVID-19 after they were vaccinated. All of the deaths were people between 67 and 94 years old, and all had multiple underlying conditions.

Four were residents of long-term care facilities, DOH said.

RELATED: 'I don't think this is a serious issue': State health experts weigh in about 'vaccine breakthrough' cases

A "breakthrough" happens when someone tests positive for COVID-19 two weeks or more after receiving the full course of an approved COVID-19 vaccine. Breakthrough cases have been identified in 24 of the state's 39 counties.

Still, the breakthrough cases account for only .01 percent of the 1.7 million people who are fully vaccinated in Washington.

The majority of those in the state with confirmed vaccine breakthrough experienced only mild symptoms, if any, officials said, but 12 percent of the breakthrough cases in Washington required hospitalization.

Some of the cases showed evidence of variants.

"Finding evidence of vaccine breakthrough cases reminds us that, even if you have been vaccinated, you still need to wear a mask, practice social distancing, and wash your hands to prevent spreading COVID-19 to others who have not been vaccinated," said state Health Secretary Dr. Umair A. Shah. "We encourage everyone to get vaccinated as soon as they are eligible, and encourage friends, loved ones, and co-workers to do the same."

DOH officials said they will begin regular reporting of breakthrough cases in late April.

As of Wednesday (April 14), the state has reported 353,147 COVID-19 cases and 5,340 deaths.

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