Although Jenny McCarthy and her fellow anti-vaccinationists still wage their very public crusade against vaccination, there's nothing really new about their arguments. Opposition to vaccination is as old as vaccination itself.
Smallpox was once one of the most devastating and feared diseases in history. As recently as the 18th century, frequent outbreaks killed an estimated 400,000 Europeans each year and left many survivors disfigured. Especially dangerous in children, 80% of those who contracted smallpox died of the disease. When Lady Ashley Wortley Montague arranged for her son and daughter to be inoculated against smallpox in 1717 (the practice was common in Asia but was unknown in Europe), she had no idea of the storm she would unleash as a result. Although early opposition to inoculation had a valid basis (patients undergoing the first inoculation technique, also known as variolation, had an estimated 3 percent chance of developing serious complications), much of the resistance came from religious leaders. In a July 8, 1722 lecture by Edmund Massey at St. Andrew's Church in Holborn, England, he based his sermon on a passage from the Book of Job, "So went Satan forth from the presence of the Lord and smote Job with boils, from the sole of his foot, unto his crown". Massey argued that the Biblical disease in question was smallpox and added, "With this view, I will not scruple to call it a diabolical operation, usurping an authority founded neither in nature or religion. This practice also tends to support vice and immorality, inasmuch as it diminishes the salutary terror which prevails respecting the uncertain approach of this disease". In other words, being afraid of smallpox built character.
Although Edward Jenner's discovery of vaccination meant a safer alternative to variolation, it would still take many years for vaccination to be widely accepted. In 1840, the British Parliament passed the first Vaccination Act which banned variolation. The Act also gave local boards the power to vaccinate everyone in their districts but still allowed individual objectors to refuse. While vaccination campaigns led to a dramatic drop in smallpox cases, outbreaks continued to occur (especially in the growing city slums). Following pressure from medical authorities, Parliament amended the act in 1853 to make vaccination compulsory. Not only were all newborns required to be vaccinated within the first three months of life but any parent refusing to comply was fined. By 1867, the law became even more stringent with parents being prosecuted for refusing to have their children vaccinated.
It was these stringent laws that inspired the development of the anti-vaccination movement in the 1870s. One of the leading figures in the movement was William Tebb who co-founded the London Society for the Abolition of Compulsory Vaccination in 1880 (it later became the National Anti-vaccination League in 1896). A lifelong firebrand, Tebb had been prosecuted thirteen times for refusing to vaccinate his third daughter. Along with his supporters, Tebb pushed for the abolition of the Vaccination Act and an end to compulsory vaccination in the UK and abroad. Realizing that the movement needed an eminent scientist to support the anti-vaccination cause, Tebb recruited an unlikely champion: Alfred Russel Wallace.
Although Wallace was already famous for his role in the development of Charles Darwin's theory of evolution, his willingness to take on unpopular causes had earned him considerable notoriety as well. Wallace had not always been an anti-vaccinationist (his earlier writings praised Edward Jenner as a medical pioneer and he had his own children vaccinated) but his involvement with Spiritualism brought him into regular contact with anti-vaccinationists (especially Tebb). It was Tebb who persuaded Wallace to join the movement by presenting him with statistics that he had compiled concerning the risks associated with vaccination. Whether due to the statistics or his own concerns about the basic infringements on individual freedom resulting from the Vaccination Act, Wallace became a convert to the cause sometime in the early 1880s.
In fairness to Wallace, there was probably was some basis for his skepticism. At the time, nobody knew exactly why vaccination worked. Despite Louis Pasteur's research and the recent acceptance of the germ theory of disease, the science of immunology was still in its infancy. The fact that medical authorities were eagerly pushing for something that the anti-vaccinationists were condemning as "quackery" and prosecuted parents who refused to comply was enough for Wallace to get involved. Working with the statistics that Tebb provided, Wallace began his own research into vaccination and the government statistics on smallpox and vaccination. He also attempted to link incidence of smallpox to more general issues of sanitation.
While the Public Health Act of 1848 began to improve living conditions in most slums, progress remained slow and health problems related to sewage and industrial waste were still common. Wallace and his fellow anti-vaccinationists argued that smallpox and other infectious diseases were actually caused by contamination and that vaccination was likely dangerous in itself. There was (if you'll pardon the expression) a germ of truth in that since there was no generally accepted antiseptic guidelines in vaccinating children and doctors often reused the same needles on their patients. Wallace also argued that there were no controlled experiments showing how long the protection from vaccination lasted.
All of Wallace's findings were written up in a tract titled Forty-five Years of Registration Statistics, Proving Vaccination To Be Both Useless and Dangerous.Published in early 1885, Wallace compiled statistics from across Great Britain and continental Europe (where compulsory vaccination laws were also in place). Not limiting himself to smallpox, Wallace examined incidence patterns for diptheria, measles, scarlet fever, and whooping cough (pertussis). He concluded that vaccination did more harm than good and that public sanitation played a greater role in disease prevention. Almost immediately, Wallace came under attack by physicians who were horrified that a scientist of Wallace's reputation would side with the anti-vaccinationists. The fact that popular opinion was turning against mandatory vaccination (helped along by graphic stories of conscientious objectors being arrested), added to the pressure for changing the vaccination laws.
In 1889, the British government appointed a Royal Commission to evaluate mandatory vaccination policies. While Wallace turned down an offer to sit on the Commission himself, he appeared as the anti-vaccinationists' star witness. The fifteen members of the Commission included some of the prominent British physicians of that time (most of whom were pro-vaccinationists which outraged Tebb and the others). The Commissions members held twenty-one meetings in 1890 and examined ten witnesses (mostly anti-vaccinationists). Wallace appeared four times before the commission and presented all of his graphs and statistics. While the commission members were initially impressed by Wallace's testimony, that changed after they had a chance to evaluate his findings more carefully.
Wallace's statistics seemed impressive but the committee members found numerous errors that seemed unworthy of someone of Wallace's reputation. Not only did Wallace and his fellow anti-vaccinationists ignore statistics that failed to support their view but many of the statistical tables were highly selective (doubly embarrassing since Wallace had accused the pro-vaccinationists of doing the same thing). Wallace was caught off-guard by the findings and was forced to admit that many of the statistics that he had presented were worthless. While he continued to argue that sanitation was more important than vaccination, Wallace's credibility had been severely undermined by the time he concluded his testimony. Anti-vaccination activists defended Wallace throughout the entire process and accused the commission of being biased in favour of the pro-vaccinationists. One source commented that, "Dr Wallace stood an examination which proved, if nothing else, that anyone who gives anti-vaccination evidence before this commission must be prepared to keep his temper through insults which most would resent and which few would indulge".
Although the Commission issued a preliminary report in December 1890, the final report wouldn't come out until six years later. After the final report, Wallace published his most scathing pamphlet yet on the Commission's findings. Titled "Vaccination a Delusion; Its Penal Enforcement a Crime: Proved by the Official Evidence in the Reports of the Royal Commission", Wallace accused the Commission's final report as being "not only weak, misleading, inadequate but is also palpably one-sided". His critics reacted as expected and accused Wallace of simply restating all of his old arguments without providing any new evidence. Still, his crusade had some impact and the Commission's report led to changes in compulsory vaccination (penalties for noncompliance were reduced) and adoption of less risky methods of inoculation.
Wallace was hardly satisfied. He continued to write anti-vaccinationist pamphlets until his death in 1913. As one of the most well-known scientists of his generation, he lent an air of respect to the anti-vaccination crusade that it never had since. In one of the last pamphlets that he wrote for the Anti-Vaccination League in 1904, he said that "the figures go increasing and decreasing so suddenly and irregularly that by taking a few years at one period, and a few at another, you can show an increase or decrease according to what you wish to prove". Most of the arguments that he raised against vaccination are still being used by anti-vaccinationists today. Even in the 20th century, anti-vaccination societies continued to proliferate and attracted numerous "star" supporters including Wallace and George Bernard Shaw (who wrote that vaccination was "a particularly filthy piece of witchcraft"), as well as health faddists, anti-vivisectionists, trade unionists, etc.
While compulsory vaccination was eventually phased out in Britain with the introduction of the National Health Service in 1948, it still remains a thorny issue in many other countries today. The aggressive spread of vaccination campaigns across the world (in combination of containment of known cases) led to a drastic reduction in many communicable diseases for which vaccines are available. Although 50 million cases of smallpox were recorded world-wide in the 1950s, the last naturally occurring case of smallpox occurred in Somalia in 1977 and the World Health Organization declared the disease eradicated three years later. Despite equally aggressive vaccination campaigns for other diseases, the World Health Organization missed its target date of 2000 for the eradication of polio (although the campaign is still underway). Whether similar victories will be possible with measles, diphtheria, and other diseases largely depends on the success of current vaccination campaigns and the role that anti-vaccinationists will play in opposing them. There's also the fundamental question of why children in many Third World countries are still dying of diseases that are supposedly preventable through the use of vaccines.
The autism-vaccination link may only be the latest development but the basic arguments seem pretty much the same as ever. The battle continues.