Pertussis cases, otherwise known as whooping cough for its distinct sound, are surging once again after several years of relative decline.
The rising cases include San Francisco.
“Last year we had one case, and this year there have been 97 cases so far reported to us,” said Dr. Susan Philip of the San Francisco Department of Public Health.
Cases are also climbing in the Easy Bay.
One Oakland high school even sent out a letter to parents telling them about an outbreak in their community.
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Health officials say while anyone can become infected, certain groups are at higher risk.
“We worry about very young kids, less than one, being very susceptible. And then we worry as well about people who have underlying health conditions,” Dr. Philip said.
Doctors say the rise in cases is likely due to a combination of factors.
One being that whooping cough tends to be cyclical, with case spikes every three to five years.