STEPHANIE COOKSON

At the start of the COVID-19 pandemic, it was widely circulated that in 12 to 18 months, a vaccine might be available. It became a general consensus that the public needed to push to the foreseeable future and that the vaccine would put an end to the pandemic. However, experts have pointed out that this process will likely take much longer, increasing the importance of safety measures like masks and social distancing, as they may be the best defense for many months to come.

PDBY spoke to Professor Jan Verschoor from UP’s Department of Biochemistry, Genetics, and Microbiology, to find out why a vaccine may only be available at the end of 2021. “Vaccination is a solution that allows faster herd immunity and less catastrophe of pandemics”, he explained. Herd immunity is achieved when “people will literally, by natural immunity, no longer tolerate this wild juggernaut of disease. This is how all pandemics go, with various magnitudes of catastrophe in their wake,” Prof. Verschoor said. Without a vaccine, COVID-19 “will continue to increase its infectivity, decrease its fatality, and eventually disappear” as herd immunity emerges, he said. Prof. Verschoor also explained that, while COVID-19 had a 21% fatality rate across the globe in January, by June this had decreased to 6.6%. This is according to the ratio of deaths to recoveries. In South Africa, this fatality rate dropped from 4% to 2.5% over this period. “Not bad for one semester: the virus learned to infect people more cleverly by not killing them so fast”, added Prof. Verschoor. In the metaphor of the virus as a student, he explained that lockdown or quarantine is similar to admission and entrance requirements that keep new viruses, “out of established sophisticated laboratories”, in this case, the economy. “But liberal society demands more to learn faster, despite the risks, rather than risking extreme lockdown that forbids living for fear of dying”, he said.

Not bad for one semester: the virus learned to infect people more cleverly by not killing them so fast”, Prof. Verschoor

Currently, there are many vaccines for COVID-19 being developed around the world, and South Africa, alongside Brazil and the UK, human trials of a frontrunner vaccine called AZD1222, began in partnership with Oxford University. “There are three different international forerunner COVID-19 vaccines, among the already 159 attempts towards this goal, allowing for an eventual worldwide multi-pronged implementation of COVID-19 vaccination”, said Prof. Verschoor. “The forerunner COVID-19 vaccines”, he said, are made from the “genetic code of the crucial COVID vaccine spike protein, packaged into a naturally infecting, but non-replicating harmless virus vector”, he explained, this vector being “the disarmed common cold virus”. When a person is injected with this, the virus vector (in this case, disarmed common cold) “infects the body tissues where the COVID code is translated into protein and presented to your immune system for a short while to induce both cellular and antibody immune protection against COVID-19”, according to Prof. Verschoor. As of 20 July, the AZD1222 vaccine was administered to healthy hospital and university staff in the United Kingdom and South Africa and proved to be safe for them. “It generated the required protective antibodies and immune cells that are observed in patients who successfully recovered from COVID-19”, he said.

However, the process of making a widely available vaccine is a long one, and Prof. Verschoor explained why it will take some time for this to happen. “New vaccines are not without risk”, he said, citing an anti-AIDS clinical trial of a vaccine in SA “where the vaccinated experimental group became more susceptible to HIV infection than the control vaccinated group”. Testing should, therefore, be rigorous. The latest three COVID-19 vaccines “are now in phase three of clinical trials where the efficiency and side-effects of the vaccines are tested in thousands of individuals of all genders, races, and age groups, but excluding people who are known to be vulnerable, such as pregnant women, young children, the elderly, and people with compromised health conditions”, said Prof. Verschoor. The outcome of these trials is expected in December, by which time supporting pharmaceutical companies “will have manufactured millions of vaccine doses ready to initiate the protection program, but for selected populations first”, he said.

There are three different international forerunner COVID-19 vaccines, among the already 159 attempts towards this goal, allowing for an eventual worldwide multi-pronged implementation of COVID-19 vaccination

This is because healthcare workers on the frontline will be the first to benefit from the vaccination program, according to Prof. Verschoor. Vulnerable people will not be the first, because “the safety and efficacy of the vaccine need first to be clinically tried in vulnerable populations once proven safe and efficient in non-vulnerable populations”, he explained. Although, this means that “people who are most likely to die from COVID-19 will actually be the last to benefit directly from vaccination”. They will benefit indirectly “by the lower risk of contracting infection from vaccinated caretakers and healthcare workers”, said Prof. Verschoor. In the meantime, economically active people will be vaccinated, which “includes students and staff at our institutions of learning”, he added.

Taking into account that the challenges involved in achieving herd immunity are accelerated by a safe, tested vaccine, “the anticipated earliest time for complete release of all COVID-19 related constraints is by the end of 2021”, suggested Prof. Verschoor. Until then, lockdown regulations “aim at managing the well-known three D’s for avoiding airborne viral disease: Dose, Dispersion, and Distance”, he said. According to Prof. Verschoor, the three D’s work in the following way: “even young healthy students can die from COVID-19 if they inhale a large dose of virus. How does this happen? By not keeping a healthy distance from a potentially infected person, thereby inhaling large and many droplets from that person’s unmasked cough, sneeze, laughter, or loud talk. Lastly, one should allow maximum dispersion of exhaled air by ventilation”, he explained, by avoiding cramped spaces. “Please add a fourth D (diligence) to your general approach to student life during COVID lockdown. It will keep you going once the pandemic is over,” added Prof. Verschoor.

the anticipated earliest time for complete release of all COVID-19 related constraints is by the end of 2021

As for treating patients with the virus, there is uncertainty around treatments being used around the world. Blood plasma therapy, for example, involves giving an infected person the blood plasma (the liquid part of blood that holds blood cells) of someone who recovered from the virus. The idea is that when a person survives a virus, their immune system has developed antibodies to fight it, and these antibodies can be shared with other people to help their immune systems fight the same virus. However, there is no clear evidence to suggest that surviving COVID-19 makes one immune to it, as it has not been determined whether or not the virus can re-infect people. For example, in China, between 5% and 10% of people who recovered from COVID-19 tested positive after recovery, but the meaning of this statistic is also unclear, as the virus may be dormant and re-activated.

 

As for antiviral treatment, the evidence is mixed, and research for an antiviral medication to fight COVID-19 is underway. Antiviral treatment prevents a virus from replicating, or infecting more cells in the body, rather than killing the virus. According to Johns Hopkins Medicine, it can shorten the duration of illness, and lessen complications. However, research hasn’t conclusively pointed to any medications that are of particular help with COVID-19. There has also been news of the vaccine for tuberculosis, the Bacillus Calmette-Guérin (BCG) vaccine, having a positive effect on infection and survival rates. The evidence for this is also uncertain. The World Health Organisation maintains that there is (as of yet) no evidence to suggest BCG’s effectiveness for COVID-19, and Cape Town’s Tygerberg Hospital began a 500-person trial to test it in May. While conclusions have not been released, those involved in the study warned South Africans not to seek out the BCG vaccine yet.

Overall, the wait for a vaccine to end the pandemic, which has thrown the whole world a curveball, is further away than initially thought. Many months are still needed to study the virus, treatments, and vaccines before modern medical technology will bring this difficult chapter in human history to a close. In the meantime, relying on Prof. Verschoor’s suggestion of three D’s, plus diligence is the most effective way to wait out what will probably be a long journey to herd immunity.

Illustration: Sanele Zulu

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