A potential reason behind vaccination hesitancy is due to a false assumption that vaccines cause autism. On 28 February 1998, Andrew Wakefield published a paper that described 8 of 12 children whose first symptoms of autism appeared within 1 month after receiving an MMR vaccine. All 12 children were referred to a pediatric gastronenterology unit with a history of normal development followed by loss of acquired skills. 8 of these children had gastrointestinal symptoms and lymphoid nodular hyperplasia were revealed on endoscopy. From these observations, Wakefield postulated that MMR vaccine caused intestinal inflammation that led to translocation of usually nonpermeable peptides to the bloodstream, which can consequently lead to the development of autism. While there are some individuals who take his words for the truth, the Wakefield paper published in 1998 was flawed for a number of reasons. One is that about 90% of children in England received MMR at the time this paper was written. Because MMR is administered at a time when many children are diagnosed with autism, it would be expected that most children with autism would have received an MMR vaccine, and that many would have received the vaccine recently. The observation that some children with autism recently received MMR is, therefore, expected. Another reason was that some children were reported to have experienced first behavioral symptoms within days of MMR, but the records documented these as starting some months after vaccination. Although the authors claim that autism is a consequence of intestinal inflammation, intestinal symptoms were observed after so the testimonies from those children does not strongly support the hypothesis.
Another study conducted by the Danish Epidemiology Science Center published in the New England Journal of Medicine contained over 537,000 Danish children born from 1991-1998 in Denmark. The researchers compared the vaccinated group of children to the unvaccinated group and after adjusting for potential confounders, the relative risk of autistic disorder in the group of vaccinated children, as compared with the unvaccinated group, was 0.92 and the relative risk of another autistic-spectrum disorder was 0.83. As a result, the team found no association between vaccination and autism, concluding that vaccination did not put children more at risk than not vaccinating. Confidence in MMR vaccination subsequently increased after the release of this research paper, but several parents’ groups are still concerned about the possibility of a link. According to the CDC, a risk ratio (RR), also called relative risk, compares the risk of a health event (disease, injury, risk factor, or death) among one group with the risk among another group. The team from Denmark calculated the relative risk for autism with adjustment for age, calendar period, sex, birth weight, gestational age, mother’s education, and socioeconomic status. The RR was 0.92, and RR < 1 means that the risk of the outcome is decreased by the exposure, which can be called a “protective factor.” Overall, there was no increase in the risk of autistic disorder or other autistic-spectrum disorders among vaccinated children as compared with unvaccinated children.
People get so worried about the risks of vaccines that they forget to worry about the risks of the diseases vaccines prevent. Some people are afraid of vaccines because they believe vaccines bring more harm than good. Faced with the reality of COVID-19, they will have to do the math for themselves whether the risk of getting COVID-19 and experiencing serious medical problems is higher than the risk of being vaccinated. And what more, they will have to decide whether they want to be selfish and care only about themselves or they also care about people who can’t be vaccinated.
Germy Banter 