It's already claimed the lives of five infants, and doctors warned Wednesday, that if children aren't vaccinated, the whooping cough epidemic in California will spread fast.
According to the California Department of Public Health, 910 cases of whooping cough have been reported this year, as of June 15, which is a staggering increase from 2009.
The five babies who caught it and died were all younger than three months old.
Whooping cough is another name for pertussis, and the best way to protect you're children from catching it is to get their shots, according to health officials.
Doctor Joseph Scherger said hat's easier said then done.
"There has been that fear of vaccines and the fear of autism is one," he explained.
However, Scherger said that fear is unfounded.
"Very careful studies have dispelled the notion that these early childhood vaccines are contributing or causing autism," he said.
"The science backs up everything with when it comes to getting immunizations," said Catherine Romero, a concerned parent who encourages immunizations for infants. "I kind of go with that side of the story."
Scherger is vice president of primary care at Eisenhower Medical Center.
The first symptoms to look out for, he said, is a cough and running nose lasting for a week or two. The cough will then get more serious -- even causing a so-called "whooping" sound.
"It's especially deadly to infants and young children," Scherger said. "But in adults it could cause a pretty severe persistent infection."
The department of health reports 35 cases of whooping cough in Riverside County -- five of which in the eastern end of the county.
In 2009, only 17 cases were reported.
"I'm concerned about it with these guys, because there's a lot of kids," said Romero.
Doctors recommend that children receive a series of DPT shots five times before turning five years old.
DPT stands for Diphtheria, Tetanus and Pertussis.
"If you get that series of five shots: three in the infancy, one at 18 months and one at about 5 years, you will be protected until you graduate from high school," Scherger said.
Adults should then get a booster shot shortly after turning 18 "just to make sure you're not at risk for infection," Scherger said. "I mean, this [is] kind of like the swine flu type of thing. The potential is enormous for this infection."
Although the number of whooping cough cases in California are high, nationally, the numbers are down.
Vaccines are the most effective form of prevention, according to doctors.
Just get in touch with your local primary care physician or pediatrician, because the whooping cough vaccine is not is short supply.