Vaccines: Effective yet Controversial?

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In the UK, there are a number of vaccination programmes designed to reduce the incidence of disease and mortality rates. Vaccines have widely proven their effectiveness, decreasing the burden of disease worldwide, with diseases such as smallpox and polio being eradicated in the UK. However, there is a growing issue of poor uptake of certain vaccines due to health scares and anti-vax movements.

Immunisation is the process of generating immunity, or protection, against a microorganism that would otherwise cause disease. There are various ways in which immunity can be established in an individual, such as the transfer of antibodies in breast milk, through blood transfusions, and through vaccinations. Vaccines work by mimicking the infection to trick the immune system into generating a response and providing protection, while keeping the individual free from disease. A feature that makes vaccines effective is their ability to stimulate the production of a type of immune cell known as memory cells. This cell type is important in creating an immunological memory where the immune system is able to respond more rapidly and with greater efficiency, should the individual be exposed to that same microorganism again. A further advantage of vaccinations is the ability to establish herd immunity, where if a large enough proportion of the population are vaccinated, typically 95%, those that are unvaccinated are also protected.

Our current understanding of vaccinations comes from the work of Edward Jenner, often referred to as the ‘father of immunology’. In the 18th century, he observed that milkmaids who contracted cowpox were immune to smallpox. With this observation in mind, he infected a young boy with cowpox, and then later infected him with smallpox, and as predicted, the boy was found to be immune to the latter. Louis Pasteur, a French microbiologist, later coined the term ‘vaccine’, from the Latin word for cow, ‘vacca’. Pasteur discovered the therapeutic use of weakened viruses in the treatment of diseases such as rabies and anthrax.

Despite vaccines being proven to be safe and effective in treating disease, the past two decades have seen more people opposing the use of vaccines, or becoming ‘anti-vax’.

In 1998, Andrew Wakefield published a paper in the peer-reviewed journal, The Lancet, proposing a link between the administration of the measles, mumps and rubella (MMR) vaccination and the development of autism. This study focused on twelve children, who started displaying symptoms of autism within a month of receiving the MMR vaccine. The paper was found to be fraudulent for many reasons including conflicts of interest and data manipulation, which ultimately led to the paper being retracted by The Lancet. However, due to the hysteria caused by the article’s publication, it is believed to have resulted in a large drop in the number of children being vaccinated. Uptake of the MMR vaccine dropped from 92% to 84% between 1997 and 2001, falling below the World Health Organisation’s target of 95%. This fall in vaccination rates has seen an increase in the number of cases of measles, mumps and rubella in the UK, with an alarming 43,000 cases of mumps reported in 2005 alone.

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The accessibility of the internet has also led to the spread of misinformation. In fact, a survey looking into parents’ attitudes towards vaccinations revealed that 50% of parents to children under five years old, and 41% of parents to children under 18 years old, were exposed to negative information regarding vaccinations on social media.  However, the messages spread online can often neglect scientific evidence. One common concern raised by anti-vax websites is that there are harmful levels of aluminium in vaccines. However, aluminium is an important component of vaccines, boosting the immune response needed to protect against disease. Furthermore, such websites neglect to inform readers that babies consume 7 mg of aluminium through breast-milk over a period of 6 months, which is much greater than the 4 mg administered by vaccination to an infant during their first year of life.

Another vaccination programme that has been subject to fear-mongering is the human papillomavirus (HPV) vaccine, which is typically administered to 12 and 13-year-old girls. HPV is the collective name for a group of viruses, with some of the more high-risk types being associated with cervical cancer. Although the HPV vaccine does not protect against all types of the virus, it does offer protection against the forms of HPV that cause most cervical cancers. In order for full protection to be established, two doses of the vaccine are administered 6-12 months apart.  In April 2019, it was reported that Scotland had seen a 90% decrease in the number of cervical pre-cancer cases, demonstrating the effectiveness of the HPV vaccine.

However, since the introduction of the HPV vaccination in 2008, social media has played a large role in fuelling scepticism and spreading misconceptions regarding its use. Issues raised by parents include concerns of side effects and the supposed encouragement of sexual activity in teenage girls. Furthermore, a number of news articles have highlighted cases where adverse side effects, including death, have occurred. These articles, while highly emotive, omit much of the scientific facts and evidence behind these cases. However, due to the shocking nature of these rare cases, such articles are widely shared, with some boasting nearly 20,000 shares to other online platforms. As a result of these scares, 1 in 6 girls who were eligible to receive the vaccination in the 2017-2018 school year did not receive both doses, rendering it ineffective.

While a number of vaccination programmes have been met with scepticism, vaccines are important in protecting both the health of an individual, and that of the wider population. All medical treatments, including vaccines, carry the risk of side effects, so it is important to consider information from reliable sources before receiving a vaccination.

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