The Different Nature of Two Vaccines

COVID-19 and Rabies—Part 2

Last time, we left off talking about how the rabies vaccine, created in the late 19th century by Louis Pasteur, raises surprising ethical conundrums that do not arise in the case of the COVID-19 vaccine. To briefly recap, rabies is a disease that is nearly always fatal once symptoms appear, but the chance of an individual contracting rabies is exceedingly low. This is quite the opposite for COVID-19: the virus is much more contagious, but does not carry such a severe mortality rate. The total number of deaths, however, is still staggering: as of this writing, there have been just over 400,000 confirmed deaths due to the coronavirus in the United States and over 2 million deaths worldwide.

Partly due to the low chance of rabies infection and spread, a rabies vaccine is not included in the typical vaccine schedule for children or adults, as recommended by the CDC. As Gerald Geison, historian and biographer of Louis Pasteur, explains in his article about the ethics of rabies: “The potential social benefit [from a rabies vaccine] has never seemed sufficient to justify the sort of intrusion on individual rights represented by compulsory vaccination against smallpox, for example.” We could equally say, nowadays, COVID-19 vaccine instead of smallpox in that sentence.

Pasteur watches on as boy gets rabies inoculation (1885)

In the case of the coronavirus pandemic, however, the potential social benefits are immense. COVID-19 is an infectious disease that is highly transmissible between individuals, and the personal and economic costs of a surging pandemic are enormous. The COVID-19 vaccines currently being used have been seriously vetted and confirmed to be safe and effective.

The Vaccination Trial Process and Trust

That was another issue—scientific transparency—the initial rabies vaccine faced that the COVID-19 vaccines do not. We saw in the first post from the series the lengths to which Pfizer and other drug companies go in order to prove the vaccine is safe and effective. At the time of Pasteur and his rabies vaccine, the same could not be said. He kept his work very private, and, naturally, people were skeptical; a French mother in 1885 probably asked at some point: “How do you know the rabies vaccine is safe and effective?” just as you or the people around you might be wondering how we know the COVID-19 vaccines are safe and effective.

We know the vaccine is safe because, unlike Pasteur who hid the data, the Food and Drug Administration (FDA) has published all the information. You can see exactly what the FDA reviewed to make their determination to approve Emergency Use Authorization. And the data are very convincing.

The Known and Potential Benefits

In the words of the Food and Drug Administration when it approved the Pfizer/BioNTech vaccine, “the known and potential benefits outweigh the known and potential risks.” That is to say, the possible harm caused by the the COVID-19 vaccine—possible mild symptoms following the injection that lasts for a short time, slight infringement on individual rights, and low-risk future side-effects—is significantly lower than the benefits a widespread vaccination campaign would bring, namely a lower number of COVID-19 infections and deaths, the re-opening of businesses and schools, and a general return to normal day-to-day life. 

What were the specific known benefits presented to the FDA committee in their risk assessment? The Emergency Use Authorization lists 3 main benefits:

  1. Reduction in the risk of confirmed COVID-19 occurring at least 7 days after Dose 1
  2. Reduction in the risk of confirmed COVID-19 after Dose 1 and before Dose 2
  3. Reduction in the risk of confirmed severe COVID-19 any time after Dose 1.

And the known risks? A fairly high frequency of some side effects like fatigue and headache, but these mild symptoms only lasted a few days.

All in all, the ethics and science are clear: administering the vaccine is a good, safe, and effective decision. And as more and more people get the vaccine, more and more information will be published about any possible side effects, which in turn will be acted upon by doctors and scientists around the world.

Further Reading


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