As the race to develop an effective COVID-19 vaccine continues, the battle between the science of vaccines and the pseudo-scientific anti-vaccine movement continues to bubble. Debunking the mythology and conspiracies surrounding immunisation, as well as informing the public on vaccine safety and effectiveness, are key to halt disease spread and prevent deaths. This article series will explore the common misconceptions surrounding vaccination and present the scientific explanations which refute such concerns.
Vaccine hesitancy, colloquially termed ‘anti-vax’, is the refusal to be vaccinated, or allow childhood vaccination, against deadly diseases. This ideology was propelled into the mainstream following the publication of Andrew Wakefield’s infamous 1998 paper, ’Ileal-lymphoid-nodular hyperplasia, non-specific colitis, and pervasive developmental disorder in children’. Perhaps less well known by its full title, Wakefield presented in this paper that there is a link between the childhood MMR vaccine and the onset of autism. Whilst this paper was retracted following multiple large-scale studies disproving this finding, the damage was done in public opinion. The scaremongering led to a scepticism surrounding vaccine safety and reduction in vaccine uptake.
Vaccines – The Helping Hands to our Immune System
Vaccines are an artificial tool used to enhance our immune systems against specific disease-causing viruses and bacteria (termed pathogens). Immunity refers to the biological mechanisms and components which are deployed to help fight infection by such pathogens. We have two main sources of immune response; the rapid, innate non-specific immune system, and the slower acting, but much more specific, adaptive immune system. Whilst the innate immune system provides the first line of defence, fine-tuning the adaptive immune system provides a more targeted and robust immune response against a specific pathogenic species. This development can occur naturally – through consuming breast milk as children– or through artificial means, i.e. vaccines.
Used as early as the year 1000AD in China and India to protect against smallpox, vaccination has helped us fight these invisible killers through the ages. Although, it is safe to say that modern science has enhanced vaccination techniques to beyond rubbing smallpox scabs into open wounds and up the nostrils of patients. Now we have a range of vaccines for a vast array of deadly diseases, without a ground-down scab in sight.
Vaccines work by priming the immune system to a future infection. Put simply, vaccines present a recognisable pathogenic protein or sugar to the host immune cells. By doing this, the body recalls this specific pathogen in the events of future infection and mounts the appropriate attack to deal with it. The protein/sugar structures may be presented using a whole attenuated (weakened) pathogen cell, such as in the MMR, chickenpox or BCG vaccines. However, this method may prove risky in those who are immunocompromised through illness or other drug treatments. As a result, inactivated vaccines may be used, where the whole bacteria or virus has been killed but the small recognisable structures remain in order to trigger an immune response. Inactivated vaccines span a wide range of subclasses including: conjugate vaccines (Hib tetanus vaccine), and toxoid vaccines (diphtheria vaccine). Recombinant vaccines take advantage of yeast growth rates to quickly multiply up the number of cells presenting the active ingredient found in the pathogenic cell – used in the Hepatitis B and HPV vaccines.
Regardless of the presentation method, the immune system utilises lymphocytes to remember the specific pathogen as part of the adaptive immune response, and mount a large-scale, effective attack on the specific pathogen in the event of a future infection.
The Impact of Anti-Vax
The danger of the anti-vax movement is seen with a catastrophic effect on global human health. Thanks to the early work of Edward Jenner (sometimes referred to as ‘the father of vaccinology’) in the 18th century, smallpox has been eradicated from the Earth since 1980. Unfortunately, other prevalent diseases have not experienced the same fate. Following Wakefield’s paper, cases of mumps (a viral infection covered by the MMR vaccine), have seen a resurgence. As recently as 2019 there has been a 4× greater number of mumps cases as seen in the previous year in the UK, due to lack of vaccination. Beyond obvious practical issues of vaccine distribution and rural access, vaccine hesitancy is damaging the effectiveness of immunological protection around the world. In fact, the WHO has noted vaccine hesitancy as a top 10 threat to global health – featuring among the ranks of climate change, non-communicable diseases and HIV – with a projected 1.5 million lives saved if vaccine uptake increases. The debunking of concern and mythology surrounding vaccinations is a step towards getting those who have ready access to vaccines to help save lives around the world.
This series of articles will investigate arguments of toxic contaminants within vaccines, the idea of herd immunity, the frequently mentioned links between vaccines and autism, and the more outlandish conspiracy theories which obscure vaccines and their effectiveness in a shroud of misunderstanding and confusion.
