By: Lizzie Fu
As the COVID-19 vaccine rollout dominates the news, you might be feeling overwhelmed with all the information, wondering which vaccine is the most effective and questioning how the vaccines are being distributed. Maybe you’re asking, what are countries fighting about when it comes to the vaccine? Or even, how exactly do vaccines work again? These questions are not uncommon when looking back on the history of vaccines. Vaccines have proven to be a complex scientific journey, one that intertwines discrimination, politics, public health, and technology in humankind’s constant desire to advance knowledge. So, how exactly did vaccines come to be, what techniques do they use to immunize us from illnesses, and how do they play a role in health and politics?
A Short History
Legend has it that Buddhist monks suffering from snake bites drank snake venom to inoculate themselves. This was started from imagination, and as John Dewey, an American philosopher, wrote, “Every great advance in science has issued from a new audacity of the imagination.” So while it may not have been scientifically understood, this method amazingly worked and hence somehow got passed on to other parts of the world, particularly China
and the Ottoman Empire. As noticed by Lady Mary Montagu in 1717, women from the Ottoman harems inoculated themselves against smallpox, inserting “a matter” into the vein via a needle.
Lady Mary tried to bring this novelty to Britain, even successfully inoculating her son against smallpox, but she was met with disdain. The British, Christian doctors refused to take an untrained aristocrat who was even more, a woman, seriously. Furthermore, their bias against Muslims interfered with them trusting this development. As Eamonn Gearon, English Arabist, describes it, “Opponents of the procedure derided it as oriental, irreligious, and a fad of ignorant women.” Whether surprisingly or unsurprisingly, it seems sexism and religious superiority proved obstacles to vaccines being properly introduced to the West and the colonies of their empires.
Vaccines needed people like Edward Jenner, a British physician who developed the use of cowpox to inoculate against smallpox, and Louis Pasteur, a French biologist who helped formulate the mechanisms to make vaccines for humans, to validate them. Both Jenner and Pasteur adhered strictly to the Western scientific method of rigorous testing and peer review and were fellows of the Royal Society and Académie de Médecine respectively. This gave them authority, so their advancements were accepted by Western governments and societies - as demonstrated by the US 1902 Biologics Control Act, for example, which formally recognized and regulated the use of vaccines in Medicine. However, neither Jenner or Pasteur really understood the science behind vaccines. Rather, they simply showed how vaccinated groups seemed immune or reacted less to the particular disease.
Technology and Today
Which leads us to asking about how vaccines really work in today’s world and why they are in the news so often, especially during this pandemic.
As we now know from much study, when pathogens like bacteria, viruses, parasites or fungi make it pass barriers like skin, mucus, and cilia and infect the body, our immune systems create antibodies that recognize their antigens. Once the antigen-specific antibodies are produced, they work with the rest of the immune system to stop the disease and also create antibody-producing memory cells, which remain alive even after the pathogen is defeated. This means that if the person is exposed to the pathogen again, their immune system will be able to respond immediately, protecting against disease. But when the human body is exposed to an antigen for the first time, it takes time for the immune system to respond and produce antibodies specific to that antigen, so in the meantime, the person is susceptible to becoming ill.
This is where vaccines can really help. Vaccines traditionally contain weakened or inactive antigens of a specific pathogen that triggers an immune response within the body, but newer vaccines can contain the instructions for producing antigens rather than the antigen itself. Regardless, this weakened version will not cause the disease in the person receiving the vaccine, but it will prompt their immune system to respond much as it would have on its first reaction to the actual pathogen
. A great thing is that antibodies to one pathogen can actually protect against another pathogen if the two pathogens are very similar to each other, like cousins. Jenner took advantage of this by using cowpox to create a smallpox vaccine. Some vaccines require multiple doses, given weeks or months apart. This is sometimes needed to allow for the production of long-lived antibodies and development of memory cells. In this way, the body is trained to fight the specific disease-causing organism, building up memory of the pathogen so as to rapidly fight it if and when exposed in the future.
When it comes to COVID-19, there are currently three major Western vaccines that have been widely approved: the Pfizer/BioNTech vaccine (BNT162b2), the ModernaTX, Inc. vaccine (mRNA-1273), and the AstraZeneca vaccine in collaboration with the University of Oxford (AZD1222). The Pfizer and Moderna vaccines are both mRNA vaccines, which basically means that they contain an instruction manual to teach our cells to make a harmless piece of what is called the “spike protein”, found on the surface of the COVID-19 virus, SARS-CoV-2. This protein will then trigger an immune response from our bodies. In contrast, the AstraZeneca vaccine is an adenovirus-based vaccine, which means that it uses a replication-deficient chimpanzee viral vector based on a weakened version of a common cold virus (adenovirus) that causes infections in chimpanzees and contains the genetic material of the SARS-CoV-2 virus spike protein.
Although the clinical trials show the Pfizer and Moderna vaccines to have higher efficacy rates than the AstraZeneca vaccine (95% and 94.5% vs. 90%), their technology is quite new. mRNA jabs have not been brought to this scale, which is leading many to be afraid of them. Additionally, concerns about the COVID-19 vaccine becoming a big-pharma monopoly has garnered criticism against the pharmaceutical companies for how much they might charge countries for the supplies, making the situation a story about money. On the one hand, some argue that the vaccines may not have been developed as quickly without the competition, but on the other hand, competition has made the scramble for the vaccines vicious. Many are worried for African countries, for instance, who are being left behind with difficult access to enough vaccines. Wealthier governments and wealthier people are gobbling up the stocks, the EU even threatening to block vaccine exports as it fights to secure enough vaccines. Even within countries, debates on how the vaccine should be distributed rule the news. In the UK, it has mostly been organized by age. In the US, however, distribution differs between states, reflected in the stories of people sneaking into different states, hoping to get the vaccine at the expense of the more vulnerable. It is a classic model of supply and demand, and it illustrates the disparities in countries’ economies and governments.
Nevertheless, if you are offered the vaccine, health experts say you should take it. People with underlying health conditions that weaken their immune systems or who have severe allergies to some vaccine components may not be able to get vaccinated. Yet, when a lot of people in a community are vaccinated, the pathogen has a hard time circulating because most of the people it encounters are immune. The more people vaccinated, the less likely people who are unable to be protected by vaccines are at risk of being exposed to the harmful pathogens. This is called herd immunity. Vaccinating not only protects yourself, but also protects those in the community who are unable to be vaccinated.
We have all been acquainted with vaccines, whether it be through our annual flu jabs or in the news, and while there remains a significant minority of anti-vaxxers who still do not accept the science behind vaccines or view it as too “unnatural”, vaccines have grown to be valued as an answer to diseases. They have managed to eradicate the life-threatening disease of smallpox and an ongoing effort continues to rid the world of polio. Over several decades, polio vaccination, using routine immunization visits and mass vaccination campaigns, has taken place in all continents. In August 2020, the African continent was certified wild poliovirus free, joining all other parts of the world except Pakistan and Afghanistan. Today new techniques, like the COVID-19 mRNA vaccines, are being developed, and exciting revolutionary possibilities like using IgE antibodies to mediate against nut allergies - as published in a paper under the heading “Vaccination against Allergy: A Paradigm Shift?” - or vaccines against Alzheimer’s may be under way. It is evident that vaccines have really changed our lives and the world, and one can only look forward to what the future may hold!
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