A-YEAR-and-a-half ago, a vaccines expert in the eastern US received a phone call at home. The man on the line did not identify himself; he simply stated the names and ages of the researcher鈥檚 two children and the schools they attended, then hung up. The threat was shocking, but not a surprise. 鈥淚 get hate mail every day,鈥� says the researcher, who asked not to be named.
Many vaccine scientists in the US have received similar threats in recent years. They are thought to come from a hard core of parents who, in the face of overwhelming evidence to the contrary, are convinced that small amounts of mercury in vaccines have made their children autistic. What鈥檚 more, they believe that researchers are complicit in the scandal.
Threatening phone calls are extreme, but vaccine controversies are not. In the UK, confidence in the measles-mumps-rubella vaccine (MMR) has only recently recovered from the damage done by claims, now recognised as groundless, that it was linked to autism. Global attempts to eradicate polio hit the buffers in Nigeria in 2003 after rumours circulated that the vaccine had been deliberately contaminated with anti-fertility drugs and HIV.
Advertisement
These are just the latest in a line of vaccine scares which date back to the very first vaccines in the 1800s. Then, campaigners protested against the widespread smallpox vaccination which targeted low-income areas, believing it to be an establishment plot to harm the poor.
So what is it about one of the greatest innovations in medicine that generates such fears, and how can governments prevent anxieties turning into large-scale boycotts?
Nigeria is a case in point. It is one of just a handful of countries where polio is undefeated and is one target of a project run by the World 91色情片 Organization and others that aims to eliminate the disease. By 2003, vaccination teams from the Global Polio Eradication Initiative had fanned out across Nigeria. Then Muslim leaders in the north of the country began to attack the project.
To outsiders, the rhetoric sounded absurd. 鈥淲e believe that modern-day Hitlers have deliberately adulterated the oral polio vaccines with anti-fertility drugs and contaminated it with certain viruses which are known to cause HIV and AIDS,鈥� said Datti Ahmed, a medical doctor and chairman of the Supreme Council for Sharia in Nigeria.
Yet it struck a chord with many Nigerians. Less than a decade earlier, the Nigerian government had accused US pharmaceutical giant Pfizer of testing drugs in the country without fully informing patients of the risks. The case is ongoing, yet the allegations, which the company denies, attracted national attention, arousing suspicion against foreign medical organisations and also fuelling wider anger among Muslims over US foreign policy. In the north of the country, where Ahmed is based, there are many dilapidated health clinics in dire need of an upgrade. Against this background, many local people saw the vaccine teams as outsiders who were setting health priorities without stopping to ask local people what they needed 鈥� and as strangers not to be trusted.
As a result, four states in northern Nigeria 鈥� which are home to over 20 million people 鈥� pulled out of the project. One state refused to resume immunisation for over a year. The polio vaccination project is now back on track, but distrust of the vaccine remains widespread in the region.
At first sight, the fears that gripped Nigeria seem to be quite different from those in the UK or the US, but closer inspection reveals remarkably similar underlying issues. Take the UK鈥檚 MMR controversy. It started in 1998, after medical doctor Andrew Wakefield warned that it might be causing some children to develop autism. His evidence was scant: a study of just 12 children who had lost communication and other skills soon after being given the vaccination (). As in Nigeria, the speculation reached the ears of parents through widespread and often sensationalised media reports.
But the deeper issue, says medical anthropologist Rachel Casiday at Durham University, UK, is that vaccines were perceived as being forced on parents by outsiders they did not trust 鈥� in this case, the government. In a 2005 survey of attitudes to the MMR vaccine, Casiday found that parents were wary of claims that the vaccine was safe because of the way their government had underplayed the risks during a previous health scare 鈥� the controversy in the early 1990s over mad cow disease and the possibility that tainted beef was putting human health at risk. As the MMR scare continued, the UK government鈥檚 mishandling of intelligence reports on weapons of mass destruction in Iraq cut parents鈥� confidence still further (. 鈥淎 lot of people said: why should I trust what this government says about my children鈥檚 safety?鈥� says Casiday.
鈥淰accines were perceived as being forced on parents by untrustworthy outsiders鈥�
Immunisation is one of the rare occasions when governments attempt to force a medical solution on citizens, regardless of their personal desires or beliefs, and this may be part of the problem. In Nigeria, for example, on top of the scare stories about HIV, the policy conflicted with local people鈥檚 reliance on traditional medicine, which views polio as being caused by a malicious spirit. In the UK, government-mandated vaccinations run counter to recent attempts to give patients more choice, says social anthropologist Melissa Leach at the University of Sussex. And in the US it clashes with the nation鈥檚 鈥渞ugged individualism鈥�, says paediatrician Robert Jacobson at the Mayo Clinic in Rochester, Minnesota. 鈥淰accines represent social health without regard to individuals,鈥� he says.
Deadly consequences
Not only that, immunisation has become a victim of its own success: the diseases it protects against are now so rare in many countries that fears about them have faded. The fact that vaccines are given to healthy children who do not appear to need treatment does not help either. With these factors in play it鈥檚 no wonder that fears about vaccine safety catch on, no matter how ill-founded. And when anxieties spiral into boycotts, the consequences are serious.
At the very least, the drop in immunisation rates that followed the MMR scare, from over 90 per cent to around 80 per cent, contributed to hundreds of extra cases of measles in the UK. Polio spread to all of Nigeria鈥檚 neighbours in 2004 鈥� countries that had previously been free of the disease. And when a series of anti-vaccine campaigns criticised the safety of the whooping cough vaccine during the 1970s, incidence of whooping cough spiked. One analysis found it to be 10 to 100 times more common in countries where anti-vaccine campaigns had been most effective ().
So how can a fear of vaccination be countered once it has taken root? Unfortunately, attempts to educate people about its benefits often fail. In Nigeria, the WHO and its partners tried to counter religious rhetoric by reassuring local people about the vaccine鈥檚 safety record. This attempt, according to Leach, underlined a general assumption that the villagers were simply ignorant and in need of education in scientific ways of thinking. Some believe this paternalistic approach, with few concessions to local beliefs, may even have strengthened the boycott.
Public health officials in the UK made similar mistakes, attempting to fight fears with facts. They issued leaflets comparing the relative risks of the MMR vaccine鈥檚 extremely rare side effects with the risks associated with forgoing vaccination. 鈥淟ittle tables showing relative risks of measles and the vaccination didn鈥檛 fit into the frame of reference that the parents used,鈥� Casiday says. Instead, officials should focus on the welfare of individual children by emphasising the risk that a child faces by not receiving the vaccine, for example.
This approach is far from perfect, and responding directly to parents鈥� concerns can create problems of its own, as the story of mercury in vaccines shows. The current fears about childhood vaccinations in the US date from 1997, when Congress asked the Food and Drug Administration to measure the levels of thimerosal, a mercury-containing preservative found in many vaccines. The analysis showed that by six months of age, children could have been exposed to 187.5 micrograms of mercury. Safety standards for thimerosal did not exist, but that quantity was more than 80 micrograms above the recommended limit for methylmercury, a related compound. That prompted safety fears about thimerosal, even though studies into the mercury consumed by eating tainted fish suggested that the levels in the vaccines were not dangerous.
Public health officials dealt with this by insisting that vaccines were safe, but said they would make them even safer by removing thimerosal from all vaccines. This, says paediatrician Paul Offit at the University of Pennsylvania in Philadelphia, led parents to reason that they could protect their children by avoiding thimerosal. At the time this meant avoiding vaccines in general. 鈥淲e put a scarlet letter on that product,鈥� says Offit. 鈥淲e dug a hole for ourselves from which we haven鈥檛 escaped.鈥�
Confronted with a similar dilemma, the UK authorities did the opposite. When Wakefield aired his concerns in 1998, he suggested that it might be safer to deliver the three components separately and at different times to avoid straining infants鈥� immune systems. That would have reassured many worried parents, but public health officials feared that some parents would miss at least one appointment, leaving their children under-vaccinated. At the height of the MMR scare, that decision earned the government some harsh criticism. Almost a decade later, with confidence in the vaccine now slowly returning, its position has been vindicated.
Each vaccine controversy is different, but the British experience suggests that gentle persuasion is only part of the solution. The ideal way to discuss vaccines is often a subtle mix of talking less and listening more. And sometimes having the courage to make a tough call.
