The Washington State Department of Health says a new study shows the most commonly used pertussis, or whooping cough, vaccine can wear off over time.

But, according to the Department, it's still the best deterrent against this growing health issue.

The May edition of the journal Pediatrics studied the data from the 2012 whooping cough epidemic in Washington state, and found that the pertussis vaccine, or Tdap,  can wear off after 2 to four years.

According to the Department:

“Whooping cough shots are not perfect, but they’re still the best way to protect yourself, your family, and especially babies from the disease,” said Chas DeBolt, communicable disease epidemiologist for the Department of Health and one of the lead authors of the study. “The vaccine is most effective during the first year after it is given, so it’s especially important that pregnant moms get the vaccine during the third trimester of each pregnancy so they can pass on protection to their babies.”

During the 2012 epidemic, about 5,000 cases of the illness were officially documented, the most in our state since 1941.  Health officials have not exactly pinpointed why the upsurge in cases, but remind all citizens getting the vaccine is still preferred as the best way to prevent it.  Whooping cough is especially hard on elderly or infant patients, or those who are in poor health.

So far this year, it is on the rise as well. 387 cases reported as of April 25th, compared with 87 in the same time frame as 2014.

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