(NEW YORK) — In 2012, more than 48,000 cases of whooping cough were reported in the U.S. – the greatest single-year total since 1955 – and researchers want to know why.
Now, new research published Monday in the journal Pediatrics indicates it may be that the “new” vaccine wears off after a few years, leaving kids once again vulnerable to infection.
Researchers investigating a whopping cough outbreak in Washington state found that children born after 1998, when the newer form of the vaccine was introduced, meant to have less pain after injection, had fewer antibodies in their blood.
The effectiveness of the newer vaccine decreased from 73.1 percent in the first twelve months to only 34.2 percent over the next 1 to 3 years.
Researchers suggest it may be time to go back to the old vaccine, and emphasize that pregnant women should get the vaccine to protect their infants, who can’t be given the shot in the first months of life.
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