When people stop vaccinating their children, disease breaks out. It's that simple. It's happening in Africa, and it's happening in the U.S., and if trends continue it's going to get worse.
The biggest recent case has been Nigeria, where In 2003, Islamic religious leaders called on their followers to boycott UN-provided polio vaccines, claiming they were contaminated. UN and Nigerian government officials performed additional testing and retesting of the vaccines and found nothing, but fear proved stronger than science, and four state governments halted their immunization programs. The result was an outbreak of polio, which effects mainly children. In 3 to 4% of cases, the disease destroys nerve cells that move muscles, resulting in paralysis and suffocation. Nigerian infection rates increased 30-fold, and polio spread to 10 other countries, many of which had previously been polio-free. This disaster halted a global program to eradicate polio, just when its goal was almost in reach. The anti-vaccination sentiment remains strong in northern Nigeria, largely due to religious objections, and one state has yet to resume vaccination.
The U.S. is not immune to the outbreaks of once-rare childhood diseases. There are currently four ongoing outbreaks of measles, all centered in communities with high numbers of unvaccinated children. In all cases the outbreak was traced to people returning from Switzerland, where 15% of children are unvaccinated, and 1,297 cases have been reported this year.
These U.S. oubreaks point to a future in which formerly rare childhood diseases could become commonplace again. Why? because anti-immunization sentiment is growing from several sources, ranging from religious strictures to distrust of the government, big pharma and the medical establishment.
In Colorado, up to 7% of children are "exempt" from being vaccinated under the state's notoriously lax exemption program. This threatens the entire population's protection under the principle of 'herd immunity,' under which the odds of encountering a disease drop with the level of immunity of the general population. As more of the population drops its defenses, the riper it is for infection. Children who cannot be innoculated because of autoimmune diseases or other medical problems are defenseless. Other states, including Michigan and California.
Our country's childhood immunization program has been a victim of its own success - people have lost their fear of many diseases because they simply don't see them anymore. There were as many as 3 million cases of measles in 1958, leading to hundreds of deaths. In 1952 and 1953, the U.S. had polio outbreaks of 58,000 and 35,000 cases, respectively, up from a typical number of 20,000 cases a year. After measles and polio vaccination programs were introduced in the 1950s and 1960s, the number of cases of both diseases dropped to essentially zero. Until now.
It's a matter of proportional response. Parents have never seen a neighbor or family member's child sick with any of the diseases that vaccinations protect against, but they do read scare stories about supposedly harmful ingredients or side effects in vaccines. A single case in which a child has a bad reaction to a vaccine looms like a monster, blotting out the view of the millions of children who have been kept safe by them. Celebrities (such as former Playboy centerfold Jennie McCarthy) keep themselves in the public eye by pumping up hysteria about vaccines and autism. Hucksters undermine modern medicine in order to sell books promoting quack cures. Meanwhile, careful scientific studies showing that vaccines are safe and effective go ignored.
President Franklin Roosevelt - himself a victim of childhood polio - once told Americans "The only thing we have to fear is fear itself." These days, panic is king. And next to him, astride a pale horse, rides pestilence - coming soon to a child near you.
UPDATE: Large-scale polio vaccination began in the U.S. in the 1950s. The MMR measles vaccine was licensed in 1963.