7 things you didn’t know about: vaccines

Image: Alaister Russell/The Sunday Times

With the startling peculiarity of a global pandemic foremost in all of our minds right now, it’s fair to say that the whole world is watching with baited breath for when a universally accepted vaccine will be available.

But how much do you actually know about the ins and outs of inoculation? In the spirit of swift scientific innovation, here are seven things you might not have known about vaccines.

1. The first vaccine was developed 1796 

Smallpox is the first (and, so far, only) dread disease to have been completely eradicated by a vaccination. Edward Jenner developed a vaccine in the late 18th century, after noticing that milkmaids who contracted cowpox seemed to be immune to smallpox thereafter. Using material from cowpox sores, Jenner successfully inoculated his first subjects against the related (but far more deadly) smallpox virus.

2.  “Herd immunity” is achieved predominantly through vaccination

When the majority of a population is inoculated against a disease, it facilitates a state of “herd immunity”. This means that even unvaccinated individuals are largely protected from a disease such as, for example, polio, because the vaccinated majority interrupts the spread of the virus from person to person, and thus inhibits major outbreaks.

3.  No correlation between infant vaccination and autism has been proven

A large contingent of “anti-vaxxers” (people who are opposed to vaccination) contend that vaccines are linked to the development of autism in young children. However, leading scientists and researchers have repeatedly shown that there is no truth to this claim: it has been shown that thimerosal, the mercury-based ingredient at the heart of anti-vaxxers’ allegations, definitively does not cause or precipitate ASD in children.

4. Not all vaccines are given by injection 

As scores of people do not enjoy being injected, some vaccines are designed to be taken orally. For a vaccine to be taken orally, it must not be susceptible to the acid found in the gastrointestinal tract. The vaccine must be absorbable by the gut and no absorption, means the vaccine will not work.

5. Immunisation can begin in the womb

Often, physicians will recommend that pregnant women receive influenza and Tdap vaccines while they are still pregnant (Tdap protects against tetanus, diphtheria, and whooping cough.) This is so unborn infants receive a degree of exposure to the pathogens in question before they are old enough to undergo vaccination themselves.

6. Vaccines actually help combat antibiotic resistance

The overuse of antibiotics is a serious problem, as it ultimately creates antibiotic-resistant strains of infection and reduces the efficacy of antibiotic drugs. Vaccinations are an important alternative to antibiotics: if fewer people contract a disease in the first place, fewer people will require or use the relevant antibiotics, thus curbing our over-consumption of this vital resource. Right now, there aren’t vaccines for many of the ailments that require antibiotics, but that could rapidly change in the near future.

7. Approximately 1.5-million children a year still die of preventable diseases

Vaccination works, and especially in war-torn countries where vaccination is not currently possible, there has been a clearly discernable increase in the incidence of vaccine-preventable diseases and deaths. Moreover, myths and stigma around vaccination have prevented a new generation of parents from vaccinating their children in so-called “developed” countries, which in turn has led to a resurgence of nowadays rare diseases, like measles.