Caution with the Covid vaccine

Published in Expansión

Throughout these confusing months, the surprising doubts created about natural immunization by those who had passed the Covid have contrasted with a paradoxical and excessive hope in the arrival of an artificial immunization resulting from a vaccine that, as we will see, we must contemplate with enormous doses of prudence.

Since the end of the 18th century, when Jenner verified the scientific nature of the customary practice of farmers deliberately exposing themselves to cowpox in order to get immunized against the dangerous human smallpox virus (for example, by milking an infected cow with scratched hands), the vaccine, developed by Pasteur a century later, is perhaps one of the most noteworthy milestones in medicine behind penicillin, discovered by the great Fleming. Vaccines such as smallpox, polio and measles have been tremendously beneficial to humanity. Others, not so much: flu vaccines are less than 50%[1] effective (the 2014/15 vaccine was only 19% effective and the 2018/19 vaccine 29% effective[2]) and a small number of them have implied health risks disproportionate to the benefits obtained[3], a key measure to recommend or discourage any medical treatment and avoid massive iatrogenic damage. Therefore, the recognition of the evident usefulness of vaccines that have been tested over time to safely prevent potentially serious diseases does not imply having a blind trust in each and every one of them, but rather we must always demand compliance with three requirements: efficacy, safety and necessity.

There are good reasons to be particularly cautious about the Covid-19 vaccine, which is being developed too quickly in an environment of enormous political pressure. First, no vaccine against any type of coronavirus has never been approved and the technologies used in this vaccine are in many cases new and untested[4]. Many vaccines take between seven and ten years to be perfected[5], while less than a year is being invested in the Covid vaccine and the regulatory authorities have ensured their “flexibility” to accelerate its approval[6]. This carries obvious risks.

Secondly, the economic incentive may distort the development process and tempt pharmaceutical companies to seek shortcuts of questionable ethics. Billions of doses would mean potential revenues of hundreds of billions of dollars in regular post-pandemic vaccinations, and it would certainly not be the first time that an inordinate lust for profit has blinded companies in the industry.

Third, some pharmaceutical companies that have signed pre-sale contracts with various governments have included a clause exempting them from any liability for potential side effects of the vaccine[7]. This is a perverse incentive that may weaken the essential safety requirement.

Finally, some vaccines worsen the consequences of subsequent infections instead of preventing them, which has led to the halt of distribution of some dengue vaccines, for example. This phenomenon is called antibody-dependent enhancement or ADE and has been observed in previous attempts to develop coronavirus vaccines[8].

The first vaccine that the EU has pre-ordered (called AZD1222) is the one developed by the University of Oxford and Astrazeneca[9], which uses attenuated and genetically modified chimpanzee adenoviruses and whose phase I/II has obtained results that raise questions that can probably be extrapolated to other Covid vaccines under development. The 1,077 carefully selected individuals (all perfectly healthy) were all white and between 18 and 55 years of age, with an average age of 35 years. Since the population at risk of coronavirus is usually established beyond the age of 60 and with concomitant pathologies, the study has been conducted for a subset of the population for which Covid is only a mild disease with an estimated lethality lower than influenza. The study itself warns against the generalization of the results for this same reason. The vaccine has created an immune response theoretically effective and no serious sequelae in the short term, but 70% of those vaccinated suffered fatigue and headaches, about 60% muscular pain, general malaise or chills and 18% had a fever above 38 degrees Celsius, percentages significantly higher than the control population (which was injected with another vaccine and not a placebo)[10]. So much so that the study itself modified the conditions for administering high doses of acetaminophen to the participants in an attempt to mitigate these adverse effects. That is, the vaccine against Covid causes in this young and perfectly healthy population similar or more serious symptoms than those that the vast majority of them would suffer in case of passing the disease, getting in exchange a probably lower quality immunization. It is not known how the elderly or those with concomitant pathologies will react when the vaccine is administered in later clinical phases, but in my opinion these preliminary results raise rational doubts. In addition, as we become older we respond less well to vaccines, so vaccination of the elderly sometimes requires repeated doses or the use of boosters that imply greater risks.

As citizens we do have the right to be informed with complete transparency of the real benefits and potential risks of any vaccine for each segment of the population instead of being swept away in panic, allied in this case to the interests of politics and money. Dr. William Heseltine, former professor at Harvard Medical School and founder of its cancer and AIDS research centers, recently wrote in an article published in Scientific American that “it seems foolish to run toward a vaccine in 2020 if it will only have limited benefit to the population that needs it and may put healthy individuals at risk”[11].

Indeed, it would be a mistake to rush and over-rely on a vaccine (whatever it might be) that can turn us into guinea pigs if it does not meet the proper efficacy and safety requirements and that when it reaches the population in a year’s time may not be as necessary, as some herd immunity may have been achieved. Acting more cautiously may mean changing your approach: first, focusing on protecting with scientific (not political) measures the minority that is population at risk and not the vast majority that is statistically not population at risk, a more realistic and socially much less harmful goal; and secondly, instead of trying to eliminate the coronavirus (something we are obviously failing at), perhaps we should concentrate our efforts on reducing its lethality to become a mild disease, that is, focusing on the sick and not on the healthy, something that today seems like revolutionary thinking. In order to achieve this we need economic and organizational resources, best practice protocols and safe and promising treatments. We should also reinforce our first line of defense, our wonderful immune system, by strengthening vitamin D, avoiding the permanent stress generated by the infamous media campaign of terror and promoting walking outdoors and in the sun, just the opposite of the harmful farce of mandatory masks outdoors (which no other European country defends) and the destructive, useless and medieval lockdown.


Fernando del Pino Calvo-Sotelo



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