Biotech Chief Medical Officer Delivers Some Disappointing (and Some Not So Bad) News on a Vaccine

(Chinatopix via AP)

 

Dr. David States is the Chief Medical Officer of Angstrom Bio, which is located in Austin, TX. In the following Twitter thread, he explains the obstacles researchers face as they work to develop an effective vaccine for COVID-19.

Because this virus is so highly contagious, Dr. States writes, “a vaccine will need to induce durable high level immunity coronaviruses often don’t induce that kind of immunity.” He presents a study which shows that immunity starts to drops off after about two months.

COVID-19 has a high “R0.” (Some of you likely know what an R0 is, but since I did not, I’m including an explanation.) An R0 represents the disease reproduction number. How contagious is a disease? The higher the R0, the more contagious it is.

If each infected person spreads a disease to two people, it will have an R0 of 2.

Measles, for example, has an R0 of 12-18; Influenza, 1.4-1.7; Ebola, 1.5-2.5.

COVID-19 has an R0 between 3 and 5. Therefore, scientists will need to develop a strong vaccine to provide lasting immunity.

The best hope, is to produce a vaccine similar to the annual flu shot which is only about 50%. The flu shot, Dr. States says, even with a 50% rate of effectiveness, “still saves thousands of lives.” It also reduces the severity of the disease. The flu has a low R0, considerably lower than COVID-19.

The bottom line, he says, is, “yes, we all hope we’ll quickly develop a highly effective vaccine, but the biology of coronavirus and the history of veterinary vaccines suggests it may be a slog…A speculative hope is that a SARSCOV2 vaccine will reduce the severity of illness even if it doesn’t prevent infection altogether.”

The good news is that approximately 75 vaccine candidates are currently entering clinical trials. Dr. States writes that he would consider a vaccine a success if it merely reduced the severity of the disease even if it required an annual booster.

H/T: Greg P., Twitchy