Updated: Aug 1
The spring of 2020 came with a whirlwind of public health and political engagement from the public sitting by their devices to learn the latest updates about COVID-19. Usually an extensive process is used to create a vaccine that takes years to get to the point of human trials however, with the pandemic severity of COVID-19, the world has seen a significant head-start in the race for the vaccine. Figure 1 below describes the process according to the Institute of Medicine (US) Committee on the Children's Vaccine Initiative .
What is COVID-19 and why do we have a head start on the vaccine?
In the beginning COVID-19 was described as a respiratory infection, then it was described by a variety of symptoms, and many have associated it with the flu, a cold, bronchitis, and even pneumonia but exactly what is COVID-19 and how is it that we are able to develop a vaccination for it so quickly. A March 2020 study analyzed the associations SARS CoV-2 has with other coronaviruses and the immune response predictions to SARS CoV-2. In 2002 and 2003 outbreaks of Severe Acute Respiratory Syndrome (SARS) nearly reached a global pandemic and similar events occurred in 2011 with Middle East Respiratory Syndrome (MERS) that were illnesses developed from coronaviruses SARS-CoV-1 and MERS-CoV-1. Coronaviruses which are typically seasonal virus typically develop a range of respiratory conflicts including the common cold and pneumonia in the inflicted, and many strains mutate to develop higher immune bypass and response mechanisms . In December of 2019, the world suffered yet another coronavirus outbreak attacking producing yet again another severe respiratory disease that was investigated to have originated in Wuhan, Hubei, China. In January of 2020 the coronavirus was named SARS-CoV-2. The name is appropriate referencing to the 79% genomic similarity to SARS CoV-1 and 50% genomic similarity to MERS CoV-1 .
How did we get to human trials so quickly when the process is so extensive?
“Good vaccines must meet basic criteria of safety, purity, potency, and efficacy.” (Prompetchara, E. et. al., 2020)
A major factor in meeting their criteria is researching a host’s immune response to the virus. A March 2020 study evaluated how research determined this factor. With the openly accessible genetic sequence shared by researchers in China, prior data from previous experiments were used to analyze and predict how a host immune system would respond to the SARS CoV-2 virus based on the responses to the closely related SARS CoV-1 and MERS CoV-2 viruses . Very few reports have been published on immune responses directly from SARS CoV-2, this precisely is why the process takes years and why the entire scale of this vaccination production feels rushed. Two studies noted that inflicted patients expressed an increased inflammatory response and decreased immune defense cell count which also correlates with disease severity and death rates . Seeing that the host inflicted with SARS CoV-2 can transmit the virus asymptomatic, without showing the initial inflammatory response, led scientist to believe that SARS CoV-2 has a mechanism to bypass early onset immune responses in a host . Predecessor coronaviruses have been observed to execute abilities to bypass recognition leading to a longer period of exposure to expression of symptoms. The early onset response is described in figure 2 below.
What do the prospective vaccinations look like?
Within weeks of the outbreak research teams were able to get started on the prospective vaccines. Of the various types of vaccines that have been investigated, the nucleic acid- based (DNA and RNA) vaccines seem to show the most promise from the results in animal trials. Recent mRNA vaccine designs have exhibited more stability and protein creation efficiency; therefore, it could improve immune responses in trialed patients. In the first two months of the global COVID-19 pandemic, at least 37 companies or academic institutions joined the race to develop a vaccine . Many of these institutions used some of the vaccine platform types listed in figure 3a and figure 3b below .
Will a licensed vaccination be ready by the end of summer 2020?
Human trials have begun in many countries. Further work needs to be done to collect data on the effectiveness in producing enough antibody counts to infer immunity. Following successful human trials: scalability for purchasing, production facility evaluation, recommendation reviews, and continued outbreak forecasting and target population will need to be executed for a full-scale distribution . Currently investors, governments, researchers, and the evaluation monitoring entities are collaborating to move the process along as safely and productively as possible. Priority evaluation, years of research, and monitoring systems have been expedited. Investors and governments have been drafting a plan to prepare for production and manufacturing which will have to be done before the vaccine is proven fully effective to make it available by the fall. Researchers and public health analyst are also evaluating and forecasting whether a successful decline in transmission from social distancing practices will allow for a slow lift on the regulations.
Is there even a point to getting the vaccination if quarantines are lifted by fall?
Researchers proposed testing in areas that are not under strict quarantine regulations so that they can collect data on groups that will potentially be exposed to the virus. This methodology improves the analysis of the vaccine’s effectiveness. Being vaccinated lowers the risks associated with herd immunity because your body will have a higher chance of recognizing the virus and providing a effective immune response. If the vaccine is proven effective, then the vaccine under full scale distribution could also prevent the under researched event of a secondary contraction of the virus if another wave of the outbreak occurs from lifting social distancing too early.
1. Liu, C., Zhou, O., Li, Y., Garner, L. V., Watkins, S. P., Carter, L. J., Smoot, J., Gregg, A. C., Daniels, A. C., Jervey, S., & Albaiu, D. (2020). Research and Development on Therapeutic Agents and Vaccines for COVID-19 and Related Human Coronavirus Diseases. ACS Cent. Sci. 2020, 6, 3, 315-331 https://doi.org/10.1021/acscentsci.0c00272
2. Chen, W., Strych, U., & Hotez, P.J. (2020) The SARS-CoV-2 Vaccine Pipeline: an Overview. Curr Trop Med Rep. https://doi.org/10.1007/s40475-020-00201-6
3. Prompetchara, E., Ketloy, C., & Palaga, T. (2020). Immune responses in COVID-19 and potential vaccines: Lessons learned from SARS and MERS epidemic. Available From: http://apjai-journal.org/wp-content/uploads/2020/03/1.pdf
4. Institute of Medicine (US) Committee on the Children's Vaccine Initiative: Planning Alternative Strategies; Mitchell VS, Philipose NM, Sanford JP, editors. The Children's Vaccine Initiative: Achieving the Vision. Washington (DC): National Academies Press (US); 1993. 6, Stages of Vaccine Development. Available from: https://www.ncbi.nlm.nih.gov/books/NBK236428/