Vaccination rates at elementary schools across Los Angeles are dangerously low- so low to the point where they match rates in developing countries like South Sudan, according to The Hollywood Reporter.

Elementary schools in wealthy neighborhoods across Los Angeles County's Westside, including Santa Monica, West Hollywood and Beverly Hills, have seen the number of vaccinated children plunge. The culprits are the children's elite Hollywood parents who are opting out of immunization over a belief that they are harmful or unnecessary.

State law requires children receive vaccinations for a range of diseases including measles, whopping cough, polio and the mumps. But parents can skirt the law by filing a personal belief exemption form, PBE, with the school.

While actual vaccination rates are hard to determine, the increase in filed PBE forms in Westside schools has health officials alarmed. During the 2013-14 school year, Westside preschools reported PBE levels of 9.1 percent, a 26 percent jump from two years ago, according to THR.

Seven years ago, at least 8 percent of California kindergarteners were not fully vaccinated because of personal beliefs. Now, that number has more than doubled, according to the Los Angeles Times.

Medical experts say vaccination has saved millions of kids from potentially fatal diseases like pertussis, also known as whooping cough. Officials believe if enough people are immunized, then an entire community is protected against an outbreak, a concept known as herd immunity.

"If a school has a PBE level that is so high that it crosses the herd of immunity threshold, a disease has a far higher likelihood to infect, to propagate and to reach all of the people who are not vaccinated," Dr. A. Nelson El Amin, medical director of the L.A. County Department of Public Health, told THR.

But the threshold may have already been crossed, at least in California. A whooping cough epidemic is currently underway, with 1,317 cases in Los Angeles county alone, more than any other county in the state. The disease affects adults too, but 94 percent of the California's nearly 8,000 cases involve children.

"It's a smoldering fire that has started and it could be a complete wildfire if vaccination rates continue to fall," Dr. Deborah Lehman, associate director of pediatric infectious diseases at Cedars-Sinai Medical Center, told TWR.

Parents leading the anti-vaccination movement say vaccinations, when a non-lethal disease sample is injected to build immunities, causes more harm and can lead to defects like autism, according to the LA Times.

Other parents, like Holly Blumhardt, believe their kids can stay healthy "from the inside out" by taking vitamins, eating organic food and staying active.  

"Most parents want to do the...healthiest thing for their child," Blumhardt, whose three kids are unvaccinated, told the newspaper. "It should be their choice."