The Hollywood Reporter notes that California has seen over 8,000 cases of whooping cough so far this year, of which 267 required hospitalization, including 58 in intensive care. Three infants under two months of age of died of the disease. Why? Because rich, clueless idiots are refusing to get their kids vaccinated.

The Hollywood Reporter checked filings for personal belief exemptions in tony school districts and found:

The region stretching from Malibu south to Marina del Rey and inland as far as La Cienega Boulevard (and including Santa Monica, Pacific Palisades, Brentwood, West Hollywood and Beverly Hills) averaged a 9.1 percent PBE level among preschoolers for the 2013-14 school year — a 26 percent jump from two years earlier. By comparison, L.A. County at large measured 2.2 percent in that period. Many preschools in this area spiked far higher, including Kabbalah Children's Academy in Beverly Hills (57 percent) and the Waldorf Early Childhood Center in Santa Monica (68 percent). According to World Health Organization data, such numbers are in line with immunization rates in developing countries like Chad and South Sudan.

Earlier this month the Los Angeles Times investigated the falling vaccination rates among children in various Southern California school districts. The reporters found:

California parents are deciding against vaccinating their kindergarten-age children at twice the rate they did seven years ago, a fact public health experts said is contributing to the reemergence of measles across the state and may lead to outbreaks of other serious diseases. The percentage of kindergartens in which at least 8% of students are not fully vaccinated because of personal beliefs has more than doubled as well, according to data on file with the state. That threshold is significant because communities must be immunized at a high rate to avoid widespread disease outbreaks. It is a concept known as herd immunity, and for measles and whooping cough at least 92% of kids need to be immune, experts say. … Exemption rates vary greatly by area and school. Los Angeles Unified kindergartens, for example, had an overall exemption rate of just 1.6%, although there are several in the district where more than 8% of students have belief exemptions. At Santa Monica-Malibu Unified, the overall exemption rate was 14.8% and at Capistrano Unified in south Orange County, it was 9.5%. At nearby Santa Ana Unified only 0.2% of kindergartners had exemptions on file. In Los Angeles County, the rise in personal belief exemptions is most prominent in wealthy coastal and mountain communities, The Times analysis shows. The more than 150 schools with exemption rates of 8% or higher for at least one vaccine were located in census tracts where the incomes averaged $94,500 — nearly 60% higher than the county median. The article also reports in the Montecito District in Santa Barbara that the exemption rate is 27.5 percent; Santa Cruz Montessori it's 22.6 percent.

While some might write off vaccine refusniks as voluntarily engaging in Darwinian selection, the problem is that they are putting others involuntarily at risk. As I explained elsewhere:

Vaccines do not always produce immunity, so a percentage of those who took the responsibility to be vaccinated remain vulnerable. Other defenseless people include infants who are too young to be vaccinated and individuals whose immune systems are compromised. In America today, it is estimated that about 10 million people are immuno-compromised through no fault of their own. This brings us to the important issue of "herd immunity." Herd immunity works when most people in a community are immunized against an illness, greatly reducing the chances that an infected person can pass his microbes along to other susceptible people. People who refuse vaccination for themselves and their children are free riding off of herd immunity. Even while receiving this benefit, the unvaccinated inflict the negative externality of being possible vectors of disease, threatening those 10 million most vulnerable to contagion. Vaccines are like fences. Fences keep your neighbor's livestock out of your pastures and yours out of his. Similarly, vaccines separate people's microbes. Anti-vaccination folks are taking advantage of the fact that most people around them have chosen differently, thus acting as a firewall protecting them from disease. But if enough people refuse, that firewall comes down, and innocent people get hurt. Oliver Wendell Holmes articulated a good libertarian principle when he said, "The right to swing my fist ends where the other man's nose begins." Holmes' observation is particularly salient in the case of whooping cough shots. Infants cannot be vaccinated against whooping cough (pertussis), so their protection against this dangerous disease depends upon the fact that most of the rest of us are immunized. Unfortunately, as immunization refusals have increased in recent years, so have whooping cough infections. The annual number of pertussis cases fell from 200,000 pre-vaccine to a low of 1,010 in 1976. Last year, the number of reported cases rose to 48,277, the highest since 1955. Eighteen infants died of the disease in 2012, up from just four in 1976.

For alternative opinions about vaccine refusal see Reason's debate, "Should Vaccines Be Mandatory?"