A 5-week-old San Diego infant died of pertussis, also known as whooping cough, the San Diego County Health and Human Services Agency reported Monday.
The death on Friday of the previously healthy infant was the second resulting from the highly contagious respiratory disease in California this year, and the first in San Diego since 2010, according to HHSA officials.
So far this year, 164 pertussis cases have been confirmed in San Diego, compared to 621 cases at the same time last year. There were 892 cases in San Diego in 2015.
Pertussis was rampant throughout California in 2014, when a record 2,105 cases were confirmed in San Diego. Pertussis is cyclical and peaks every three to five years, according to health officials.
"Young infants are at greatest risk of hospitalization and death from pertussis," said Dr. Wilma Wooten, the county's public health officer.
"Although the number of cases in our region has declined, this tragic death reminds us how important it is that everyone takes steps to prevent pertussis, including getting vaccinated."
It's critical for pregnant women and people who come into close contact with infants to get vaccinated, according to Wooten. Newborns are very susceptible to whooping cough because they are too young to be fully vaccinated.
It is vital for pregnant women to be vaccinated in the third trimester to give protection to their unborn infants, Wooten said.
A typical case of pertussis starts with a cough and runny nose for one to two weeks, followed by weeks to months of rapid coughing fits that sometimes end with a whooping sound. Fever, if present, is usually mild. Antibiotics can lessen the severity of symptoms and prevent the spread of the disease to others.
