Guest Post by Dr Mariah Mosley

Disclaimer: I am not specifically pro-vaccine or anti-vaccine. As a doctor, I must look at all positives and negatives of each and every treatment I could offer, because we were sworn to “First, Do No Harm” in the Hippocratic oath.  For every decision a physician makes, they must weigh these options out, and then decide if the probable benefits outweigh the possible risks.

With this being said, I do have some hesitations about the COVID19 vaccine in the works, based solely on the history we have with coronavirus vaccines, and the type of virus we are dealing with.

RNA Viruses

Viruses like HIV, Ebola, Zika, etc lead to millions of deaths every year. Have you ever noticed that there are no effective (or none at all) vaccines for these diseases? One primary reason for this is because these are very virulent RNA viruses which mutate rapidly, and have unique ways of evading the immune system. The virus infects cells by injecting RNA into the cytoplasm of the host cells to transcribe and replicate viral proteins, essentially making the human cell a virus-making factory.  It skips a step that the DNA viruses have to use, which makes the attack strategy of RNA viruses even more effective and rapidly spreading.

COVID19 is also an RNA virus, and we know there are already many different strains of it circulating the globe. There is strong speculation that with the fast replication and mutations of the coronavirus family in general, there may not be any durable or reliable immunity from that family, whether through natural exposure or through a vaccine.

The Process of Vaccine Development

Vaccines have to go through years of rigorous trials, usually on animals, before they are deemed safe enough to try with humans. It is a long, complex process often lasting 10-15 years. This is a good thing: we obviously would want our medical scientists to work out all the bugs before injecting something into us that could potentially cause harm, right?

But right now, some of the drugmakers are skipping the animal trials for the COVID19 vaccine and going straight to humans.  People pushing for faster COVID19 vaccination are forgetting there will not be a safety net without adequate time for trials and testing. Even scientists and medical experts that are making the vaccine are “concerned that it could end up worsening the infection in patients rather than preventing it”.

The History of the SARS Vaccine

We also need to remember what happened with the last coronavirus vaccine for SARS: it failed, leading to worse outcomes in the study than when people were exposed to the virus naturally (see studies below). While the SARS-CoV vaccine did induce antibody production, when the subjects in the trial were exposed to the virus afterwards, they experienced a hypersensitivity reaction against the SARS-CoV, leading to a Th2-type immunopathology. The study compared it to “the Th2-type immunopathologic reaction in young children given an inactivated RSV vaccine and subsequently infected with naturally-occurring RSV. Most of these children experienced severe disease with infection that led to a high frequency of hospitalizations; two children died from the infection.”  The last sentence of the scientific study ended with “caution in proceeding to application of a SARS-CoV vaccine in humans in indicated.” In other words, hold up, because this was definitely not what we expected!  Some are saying that COVID19 is up to 96% similar in structure to SARS-CoV, so it stands to reason that some of the same concerns may apply. 

When and if a vaccine becomes available, I urge you to do your own research, on both sides, to determine what is safest for you and your family. Be safe, my friends!


  1. As pressure for coronavirus vaccine mounts, scientists debate risks of accelerated testing–E9Nx5GBDOAFQo
  2. What are the differences between RNA and DNA viruses used in immunotherapy?
  3. 8 strains of the coronavirus are circling the globe. Here’s what clues they’re giving scientists.
  4. Immunization with SARS Coronavirus Vaccines Leads to Pulmonary Immunopathology on Challenge with the SARS Virus.
  5. As pressure for coronavirus vaccine mounts, scientists debate risks of accelerated testing–E9Nx5GBDOAFQo
  6. Vaccine Development, Testing, and Regulation.
  7. COVID-19 coronavirus epidemic has a natural origin.
  8. Scientists Compare Novel Coronavirus with SARS and MERS Viruses.