Vaccinations: Necessary or just a hassle?

A month ago, I blogged about the controversy surrounding vaccines, specifically the MMR vaccine which was wrongly accused of causing autism.  A couple weeks later, the Washington Post published an article about whooping cough and its vaccines, the histories thereof, and whether people should get immunized.

Whooping cough is caused by the Pertussis bacterium, which attacks the cells in our lungs.  Before vaccines were available, the number of cases was near 150,000 people annually.  However, when vaccinations became widely used, the number of cases dropped to a low of 1,000 in 1976.  Since then, the number of cases has increased to a peak of 25,000 in 2005.  The article addresses several reasons why this might be case.

In some states like California, it is “legal and quite easy” to refuse being vaccinated or getting your child vaccinated.  This forms groups of unvaccinated people throughout communities, and these clusters undermine a fundamental purpose of vaccinations: herd immunity.  Herd immunity works by diluting the number of cases in a community by giving a large population within the community resistance to disease.  It is a method to protect the whole population from disease, by simply protecting a majority.

However, it only works when there is an immunized “herd,” meaning people have to get immunized for herd immunity to work.  But there always seems to be reasons why people aren’t getting immunized.  Reasons might include a patient or parent’s fear of side effects from the vaccine (see MMR-Autism post), or their ignorance of the dangers of the disease.  Since whooping cough rarely occurred several decades ago, young parents might not remember the threat it poses.

Reasons could also have nothing to do with patients; their doctors could be foregoing vaccination because it is perceived as “a disease of the past,” or because they feel that evidence for a vaccine’s effectiveness is lacking.  Reasons could also orginate from the healthcare system itself; if the healthcare system doesn’t feel that immunizations are an effective intervention, then it is likely that more emphasis will be placed on treatment (which of course doesn’t help to prevent disease.)  Also, pharmaceutical companies are hugely important to the healthcare system, and may be reluctant to develop vaccines because of low cost-effectiveness.  All of these reasons may attribute to a lack of immunization in the community, but they do not fully explain why whooping cough cases are increasing.

Other contributing factors discussed by the article include mutation of Pertussis and the low effectiveness of the new vaccine compared to the old one.  There’s quite a bit of science behind each of these, and for vaccines, different types can have different efficacies.

However, in the grand scheme of things, this doesn’t mean that one shouldn’t get vaccinated.  Vaccinations won’t protect you fully but certainly it will offer a significant degree of protection (compared to having no protection).  But in order to increase vaccination, I think a few priorities have to be tackled: firstly, there must be better campaigns for vaccination for diseases that are re-emerging (emerging diseases are new, but re-emerging diseases are often forgotten by the public).  Secondly, I feel strongly that states should mandate vaccinations for all eligible.  Since not everyone is eligible (e.g. newborns often aren’t), herd immunity has already been impaired to a degree.  Having those eligible but not vaccinated is weakening herd immunity more.  Thirdly, I feel that more emphasis should be placed on federal vaccine research.  Pharmaceuticals tend not to share their data, even if it is good data that could help the population.  So if they deem a good vaccine as not cost-effective based on a poor (low profit) market for a certain vaccine, then the federal government can provide those vaccines.

Eric Wan