Recent controversies have decreased the uptake of vaccines, which has led to preventable suffering and deaths. The current scepticism towards vaccines should be countered with a clear and open education campaign.
Vaccines are among the most cost-effective ways to protect against infectious diseases. The introduction of a vaccine has, in many cases, led to a very large decrease in the incidence of the targeted disease — such as the 96% decrease in the incidence of polio that occurred within 7 years of the introduction of the Salk and Sabin polio vaccines. Vaccines have changed our way of life; in many areas of the world diseases such as polio, measles and rubella are no longer a threat, and the eradication of smallpox alone has saved hundreds of millions of lives.
Despite this impressive track record, in recent years there has been a growing scepticism of vaccines in the general public, leading to a decline in vaccine uptake. Some of this scepticism derives from scientifically inaccurate information implicating vaccines as the cause of other diseases. A well known example is the large drop in vaccination with the measles, mumps and rubella (MMR) vaccine, especially in the United Kingdom, which occurred following widespread media coverage of a report published in 1998 that suggested a link between the vaccine and autism; this report has since been debunked and was recently retracted. Similarly, the possible link between thimerosal, a mercury-based preservative that is used in vaccines, and autism has scared many parents, particularly in the United States. There is also a lack of trust in the pharmaceutical industry and the government. The recent potentially devastating influenza pandemic has been derided by some media outlets as hype stimulated by vaccine manufacturers, although independent sources have shown that the UK Government's response to the pandemic was appropriate.
The decrease in the incidence of many childhood diseases removed the urgency that was associated with vaccination
The results of this lack of trust have been devastating. By 2004, uptake of the MMR vaccine in the United Kingdom had fallen to around 80%, far below the 95% coverage that is required to halt the transmission of measles. There was a corresponding increase in the number of measles cases, which has set back the effort to eradicate measles in Europe. The recent outbreak of whooping cough in California, USA, which has caused at least five deaths, is directly linked to low vaccination rates; in some areas, one-third of school-aged children had not been vaccinated.
In part, vaccines have been a victim of their own success. The decrease in the incidence of many childhood diseases removed the urgency that was associated with vaccination, and the risks of not receiving the vaccines can therefore be perceived as low. Faced with a litany of false reports about the dangers of vaccines, parents worry — perhaps quite rightly — about the balance between the potential risks of the vaccine and the perceived benefits. That vaccinations carry risks is not in dispute. However, as clearly described on the CDC website (see Further information), the risks of vaccination are extremely low; for example, the chance of getting encephalitis or a severe allergic reaction from the MMR vaccine is one in one million, which is one-thousand times lower than the risk of getting encephalitis during a case of measles.
Several steps can be taken to improve vaccine uptake, one of which is mandatory vaccination. However, this has led to opposition from the public in several cases and will not help to restore the trust that is required to maintain high vaccination levels. A more promising approach is to improve the education of parents about the risks and benefits of vaccination. There will always be those who are distrustful of governments, vaccine manufacturers or medical professionals, but an education programme produced jointly by these groups has a chance to overcome the scepticism. By openly presenting the benefits and risks of vaccines, the public will get a clear picture of their importance and safety. Furthermore, additional research is required into the decision-making process in vaccine acceptance and refusal, which will provide valuable information to improve the effectiveness of such an outreach. However, the media plays a key part too; as an important source of news about vaccines, the media must provide accurate and balanced coverage of the successes and potential risks.
Vaccination rates need to rise, and an education effort involving all parties in the process can possibly achieve this. Medical professionals and scientists know the importance of vaccines. If we can convey this to the public, we can undo some of the harm that was done by the recent controversies.
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The necessity of vaccines. Nat Rev Microbiol 8, 532 (2010). https://doi.org/10.1038/nrmicro2417