LOS ANGELES, July 20 (Xinhua) -- As an epidemic of whooping cough, or pertussis, is sweeping California, three infants have died of the disease in the Greater Los Angeles area this year, health officials said on Tuesday.
This year, 289 possible cases have been reported in Los Angeles and 184 have been confirmed as likely, the Los Angeles Department of Public Health (LADPH) said.
The comparable number of probable cases in 2009 was 156.
The California Department of Public Health has expanded its vaccination recommendations in the face of the rising number of cases throughout the state.
Officials now recommend that anyone seven years or older who is not fully immunized, and women of childbearing age, get a booster vaccine.
"Vaccination is our best defense against pertussis," said LADPH director Dr. Jonathan Fielding. "This is a disease that is especially dangerous for infants under six months of age, who are not old enough to have received the number of vaccine doses needed to be protected against whooping cough."
He added that adults taking care of infants should get vaccinated too.
"Infants are most likely to be infected by parents, grandparents, older siblings, day care workers and other caregivers who have whooping cough but often don't know that this disease is the reason for their symptoms," Fielding said.
"People suffering from a cough illness who have contact with infants should seek medical care immediately," he said. "Anyone who lives with or has frequent contact with an infant should ensure that their vaccinations are up-to-date."
According to one recent study cited by Fielding, 41 percent of infected infants contracted pertussis from a sibling, 38 percent from their mother and 17 from their father, in cases where the source could be identified.
Typical symptoms in young children include intense coughing accompanied by a whooping sound and post-cough vomiting. Some infants infected with pertussis may not show typical symptoms, but can still suffer life-threatening complications, including pneumonia and seizures.
The primary symptom in older children and adults may be a cough that often lasts for several weeks or more.
Children should receive three primary vaccinations containing the pertussis vaccine and two boosters by age four to six, followed by a booster during their preteen years.