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As of 11 March 2020, the world has been in the midst of a pandemic. A once meaningless word to many, ‘coronavirus’ has taken the world by storm. In fact, Google revealed last December that ‘coronavirus’ was the top trending search for the UK in 2020. Coronaviruses are a family of viruses that cause infection in humans and animals. The one that led to the pandemic is called severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) but is more commonly referred to as simply ‘coronavirus’. When an individual is infected with the virus, they may display mild symptoms or no symptoms at all. Consequently, if the individual displays more severe symptoms and potentially need to be hospitalised, they are said to have coronavirus disease or COVID-19. An insidious infectious disease, the impact of COVID-19 has been catastrophic. Since the beginning of the pandemic, one clear solution to eliminate this disease and aid in the return to normal life has been the development of an effective vaccine. With COVID-19 vaccines having been approved for use in the UK and worldwide, is the pandemic finally over?
Vaccines are chemically weakened or dead forms of a pathogen, whereby a pathogen is a microorganism which results in disease. Once a person is treated with a vaccine i.e. they are vaccinated, their immune system is stimulated. This stimulation leads to destruction of the pathogen and the production of memory cells. This means that if a person was infected with the same pathogen in the future, the body remembers how to fight the pathogen. There are several types of vaccines which exist. The four main types of vaccines are live vaccines, inactivated vaccines, subunit vaccines and nucleic acid-based vaccines.
The first type, live vaccines, include commonly administered injections such as MMR and tuberculosis vaccines. As the name suggests, they contain the actual microorganism which causes the disease. However, they don’t make people ill due to attenuation, which is a process whereby the microorganisms are reduced in virulence (capability to cause severe disease). This is possible as vaccine developers only use the mutated strains of the organism that have a lower toxicity. However, as they still contain the actual disease-causing microorganism, they cause the body to produce many antibodies. This results in lifelong immunity against the disease.
The second type, inactivated vaccines, are made from dead microorganisms. They are safer compared to the live ones, but a higher dose is often needed as the bacteria and viruses don’t replicate inside the body. This makes them more expensive compared to live vaccines. An example of an inactivated vaccine is the polio vaccine. The third vaccine type are subunit vaccines, such as the hepatitis B vaccine. As the name suggests, they only include the antigen parts of the microorganism, which is the part that stimulates our body’s immune system.
The final vaccine type is the nucleic acid vaccine, which contains plasmid DNA or mRNA from the bacteria/virus that codes for the antigens that cause an immune response. These mRNA vaccines are considered safe and very effective, which is why they are increasingly being developed. The current vaccines against COVID-19 encompass the second, third and fourth vaccine types; for example, Sinopharm has produced an inactivated virus vaccine, AstraZeneca/Oxford has produced a subunit vaccine and Pfizer has produced an mRNA vaccine. Currently in the UK, the Pfizer, Moderna (another mRNA vaccine) and AstraZeneca/Oxford vaccines have all been approved for use.
A report published by Imperial College London’s Institute of Global Health Innovation (IGHI) and YouGov in November 2020 looks at people’s attitudes towards COVID-19 vaccines across 15 countries, including the UK. This report was based on survey responses from around 13,500 people and gives an insight into behaviours related to COVID-19. 65% of respondents in the UK reported being willing to get vaccinated in 2021 if a COVID-19 vaccine became available to them, which made respondents from the UK the most willing to be vaccinated among the countries surveyed. Overall, of all those surveyed, around half (51%) were willing to get a COVID-19 vaccine in 2021.
This also reveals how half of those asked, the other 49%, would be hesitant in getting a COVID-19 vaccine if it was available to them. This is not a new concept when it comes to vaccines; vaccine hesitancy has existed for many years and is in fact a global issue. The World Health Organization (WHO) recently listed vaccine hesitancy as one of their top 10 biggest threats to global health. Vaccine hesitancy is the scientific term for anti-vaccination; it is when people with access to vaccines delay or refuse vaccination. Vaccination is one of the most effective ways of eliminating disease across the world, with a staggering 2 to 3 million deaths prevented by vaccination every year. Nonetheless, vaccine hesitancy has grown in popularity in recent years, fuelled by misconceptions and misinformation. This could have potentially devastating consequences on public health.
The biggest concern people have regarding the COVID-19 vaccines is whether they are safe. Many are hesitant to be vaccinated as they feel the vaccine was developed too quickly, with the time taken from initial development to the deployment of the vaccines being approximately a year or less. Thus, people are concerned that long-term studies of the vaccines have not been conducted, and so are afraid of the potential long-term implications of a COVID-19 vaccine. An article published by the COVID Symptom Study addresses this concern. The COVID Symptom Study is the world’s largest ongoing study of COVID-19. The study is based on data provided by over 4 million people globally through the COVID Symptom Study app. It is a non-profit initiative launched by health science company ZOE in collaboration with King’s College London.
The article explains that the global health emergency created by the pandemic led to billions of pounds being committed to global COVID-19 vaccine research, as well as tens of thousands of people volunteering for the clinical trials of the vaccine. The level of funding for the vaccine meant that scientists all over the world were working on a vaccine and had the means to do so, making the process of vaccine development much faster. In addition, the large number of volunteers for clinical trials further increased the rate of vaccine development, as it can take many months or years to obtain enough volunteers. Furthermore, the genetic code of SARS-CoV-2 was identified quite quickly relative to the spread of disease (January 2020), so scientists were able to begin working on a vaccine immediately. The vaccines were not developed from scratch, rather they were developed based on existing safe and effective vaccine delivery systems. These were adapted to work against COVID-19. For example, the AstraZeneca/Oxford vaccine had been in development and testing for 15 years, having been previously developed to work against other related coronaviruses that cause SARS and MERS. In addition, compared to the past vaccines can be manufactured at a much quicker rate due to modern technology.
It is a culmination of these factors which led to the fast development of COVID-19 vaccines. If faced with vaccine hesitant members of the public, it is important to inform them that the safety precautions, clinical trials and tests for the COVID-19 vaccines were conducted as thoroughly as with any other vaccine. The spread of misinformation is especially worrying now as vulnerable patients who see or hear it may refuse the COVID-19 vaccine, thus endangering their life and the health of those around them. Ensuring we are fully educated about the history and development of this virus and its treatment can be what saves them in the future.
Authors: Amelia Ryan and Nusayba Ali