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Why vaccines, and not ivermectin, will be our only possible way out of the pandemic
Author: Hanél Sadie-Van Gijsen
Published: 03/08/2021

​Vaccines, and not ivermectin, will be our only possible way out of the pandemic, argues Dr Hanél Sadie-Van Gijsen from the Centre for Cardio-metabolic Research in Africa (CARMA) in an opinion piece for TimesLive (2 Augustus 2021).

  • Read the article below or click here for the piece as published.

Hanél Sadie-Van Gijsen*

This article is, perhaps surprisingly, not about the evidence around the usefulness of ivermectin to prevent or treat COVID-19 infection (although I have been asked about this ad nauseum by friends and family members over the last weeks).

As of Monday 26 July, there were 75 clinical trials on the use of ivermectin for COVID-19 listed on, the authoritative global database for all registered and approved clinical trials. Most of these trials are still ongoing, and there will undoubtedly be others registered in the near future, so we are probably still a long way off from the last word on that topic. But I came to the realisation that that is not the point. Even if these trials demonstrate fantastic success of ivermectin, or indeed any other drug, in the prevention and/or treatment of COVID-19 infection, such drugs will not provide us with a way out of the pandemic.

When we recover from a viral infection, it marks the end of the road for all the virus molecules you had in your body. Viruses need to infect new hosts all the time in order to keep going. However, every time a virus meets a dead end, in other words a potential new host that turns out to be immune to infection, its odds of having a future drops considerably. That is the principle behind, and the beauty of, herd immunity. If everybody, or almost everybody, is immune, the virus has no other option but to go away.

Vaccines provide long-term immune protection against viral infections, and actually have the potential to completely eradicate these diseases. We know this from our global success at eradicating polio towards the late 1990s, and small-pox in the late 1970s. International donors, led by the USA, contributed around one-third of the costs ($98 million) towards the eradication efforts of smallpox, and it was subsequently calculated that the USA recouped the total of its contributions every 26 days due to the savings of not having to vaccinate or treat smallpox anymore. That number becomes very relevant if you consider exactly how much money we currently spend on our collective COVID-19 protection and treatment measures, as well as the enormous economic costs of lockdowns, social restrictions, grants and business relief.

On the other hand, drug-based herd protection against COVID-19 may be achievable in theory, but it will require the constant cooperation of every person on the planet. That is because drugs only work for as long as we take them, and in order to end the pandemic with a drug, you would need every person around the world to take that drug every day. No room for drug hesitancy, or issues around side-effects or interactions with other drugs, no free passes for pregnant or breastfeeding women, and definitely no room for global supply shortages. And because the drug treatment will probably not involve long-term stimulation of the immune system, total eradication of the virus will be unlikely. In short, we will all be dependent on that drug, forever.

Every time somebody drops the ball, we will be back to square one. And if you take issue with the amount of money that vaccine manufacturers are earning from global vaccination programmes, imagine what it would mean for pharmaceutical companies who produce a drug, even a cheap drug that every single person on earth has to take every day for the rest of his/her life. Even small amounts of money become quite big if you multiply them by seven billion people, and then by 365 days, and then by twenty or fifty years. Talk about the gift that keeps on giving.

Doctors who treat TB patients will attest to how difficult it is to get them to take their medications consistently for 18 months. And this is for a disease that these patients actually have and presumably want to get cured of. Now imagine the odds that people will keep on consistently taking a drug, for decades to come, to prevent a disease they don't even have. I generally have faith in mankind, but I doubt this is a realistic scenario. Consequently, such a drug programme will always just be an add-on: Anti-COVID-19 drug AND masks AND social distancing. Still no return to the way things were before.

Regardless of your thoughts on the speed at which COVID-19 vaccines were originally developed and tested, we now have more than nine months of real-world data from many countries around the world that show that these vaccines are both safe and effective. In the USA, 99% of patients who died of COVID-19 over the past few months were unvaccinated. And because the same vaccines are used in South Africa and in the USA, UK and Europe, we can be guided by their data. Follow-up tests on the first receivers of both the Johnson & Johnson and Pfizer vaccines have shown that immunity against COVID-19 last for at least 9 months. (That is because these persons only received their vaccines nine months ago, and we have therefore only been able to monitor their immunity for nine months.) Towards the end of this year, we will know whether the vaccine-induced immunity lasts for a year. Towards the end of next year, we will know whether it lasts for two years. And so on, and so forth.

Research also shows a significantly stronger immune response to COVID-19 vaccines than to natural COVID-19 infection, especially in people who only had mild disease. Even if the follow-up data show that we may need booster shots, it will still be something that would need to happen only once every few years, not every single day, and it will be far less risky than building immunity through actual COVID-19 infection. Vaccination programmes can also be monitored closely, so that we know exactly how many of our fellow citizens are vaccinated. Drug programmes, on the other hand, cannot be monitored. You can hope that your colleague or the person in the queue behind you at the shop had taken his/her anti-COVID-19 medications that morning, but short of mandatory daily drug tests for everyone, we will have no way of managing and ensuring adherence to a drug-based COVID-19 prevention programme.

Of course, we should keep testing drugs for the treatment of COVID-19. It would be fantastic if we can design a treatment that would successfully treat all infections, and repurposing existing drugs will get us there faster. Therefore, I support high-quality research into ivermectin and any other drug that shows promise in this regard. But a comprehensive global vaccine programme is the only possible chance we have of finally and irreversibly finding our way out of the current pandemic. To be able to travel again. To eat in a restaurant, drink in a bar and dance in a club. To attend in-person conferences, sporting events, music concerts, festivals, religious gatherings, large wedding receptions. And yes, even funerals, where we can laugh and cry and sing and hug, without masks AND without worrying who among us will be dead next week.

*Dr Hanél Sadie-Van Gijsen is affiliated with the Centre for Cardio-metabolic Research in Africa (CARMA) in the Division of Medical Physiology at the Faculty of Medicine and Health Sciences at Stellenbosch University.