Blog Post #9: Vaccinations

I’ve got all my shots. To my knowledge, everyone I know has all their shots, too. Yet in 2015, only 84.6% of children from two to three years of age in the U.S. were vaccinated for diphtheria, tetanus, and pertussis (i.e. three of the 11 diseases for which the CDC recommends vaccination for children). While I wasn’t able to find historical rates of vaccination in the U.S. with which to compare – in Canada, as of 2017, 89% of children in the same age range are vaccinated for the same diseases. Why could this small difference in percentage possibly matter?

Herd immunity. In Japan in the 1970s, vaccination rates for pertussis (i.e. whooping cough) began to fall as parents had felt it was no longer necessary – vaccinations were so successful for pertussis at the time that whooping cough had become an uncommon illness. But in 1979, soon after vaccination rates had fallen, 13,000 people in the country contracted whooping cough (compared to only 393 people in Japan in 1974), and more than 40 had died from it. The nation’s herd immunity – the ability for a population to keep an illness contained by having most people vaccinated – was compromised.

And having a high percentage of the population vaccinated is even more important for certain illnesses. According to the Oxford Vaccine Group, 90-95% of the population needs to be vaccinated against measles to achieve herd immunity. Which is pretty high. If our vaccination rate for measles dips under this high threshold, it can cause an outbreak – which is what we saw just a year ago in Minneapolis’ Somali community.

As of 2013, only 45% of Somali-American children in Minnesota were vaccinated for measles. And of the 50 cases across Minnesota of the measles virus recorded last May, 45 were Somali-American: and thus the anti-vaccination issue is clearly not just rooted in science, but in culture as well.

The outbreak in Minneapolis’ Somali community really started in 2008, when two things happened: Somali parents were beginning to express concern over the disproportionately high rates of Somali-American children in primary school diagnosed with autism; and Andrew Wakefield, one of the chief researchers leading the campaign against childhood vaccinations (who is also considered by the scientific community to have used fraudulent research in establishing his findings), visited Minneapolis – and worked with many different anti-vaccination groups to spread the word that vaccinations cause autism in children.

This cultural influence is reflected in vaccination rates: in 2004, 92% of Somali-American children were vaccinated for measles, and that rate dropped to just 45% by 2013. Luckily, it isn’t also reflected in deaths, as no children had died from the outbreak.

Wakefield’s 1998 study, published in The Lancet, a UK journal, has since been thoroughly debunked by the scientific community. But it’s effects are lasting. Eve Dubé, a medical anthropologist, estimates that today, approximately one-third of North American parents are skeptical of vaccinations. The urgency that the study provided was effective – as many parents are scared of the possibility that their children will develop autism due to external influences (there are even groups out there who hold that the fluoride found in tap water promotes the development of autism in children) – but it’s paramount, for the sake of herd immunity and our population’s overall health, that parents critically analyze the research available (and not selectively, but instead considering both perspectives fairly) so that they can make an informed decision as to whether the fabricated possibility of their child developing autism is worth the real chance of children falling ill from not being vaccinated. But furthermore, it’s also important that our society develops a stronger infrastructure tasked with educating populations who are more at risk (e.g., because of language barriers) to ensure that false information, no matter how scientific it may look, doesn’t disproportionately harm marginalized communities.


Sources:
https://www.cdc.gov/vaccines/vac-gen/whatifstop.htm
https://www.vox.com/cards/vaccines/vaccination-rates-united-states
https://www.cdc.gov/nchs/fastats/immunize.htm
https://www.statcan.gc.ca/daily-quotidien/170628/dq170628a-eng.htm
https://www.ovg.ox.ac.uk/news/herd-immunity-how-does-it-work
https://www.npr.org/sections/health-shots/2017/05/03/526595475/understanding-the-history-behind-communities-vaccine-fears
https://www.voanews.com/a/measles-hit-minnesota-somalis-amid-low-vaccination-rates/3845863.html
https://www.cdc.gov/mmwr/volumes/66/wr/mm6627a1.htm