Are coronavirus vaccines primarily designed to improve survival rates of those already infected? No, that's not true: Vaccines are designed to reduce the risk of infection in the first place.
How will we know the vaccine is working? Will the survival rate go from 99.7% to 99.8?
This is what the post looked like at the time of writing:
(Source: Facebook screenshot taken on Wed Dec 23 16:06:22 2020 UTC)
The post, which does not mention a disease but is clearly referring to COVID-19, displays a misunderstanding of vaccines, suggesting that we won't know that the COVID-19 vaccines are working because we won't see a significant shift in the reported survival rate.
That's not how vaccines work.
Vaccines primarily work by reducing the risk of infection. The hope with the COVID-19 vaccines, as with all vaccines, is that people who otherwise would have contracted the disease, won't get it. A widespread vaccination effort would mean dramatically fewer infections, case counts and deaths.
Of course, it's entirely possible that someone who gets the vaccine could still contract COVID-19. At this early stage, experts can't say for certain what impact -- if any -- the vaccine would have on that person's outcome. However, according to the Centers for Disease Control and Prevention (CDC), the vaccine may help. Here's the CDC:
Based on what we know about vaccines for other diseases and early data from clinical trials, experts believe that getting a COVID-19 vaccine may also help keep you from getting seriously ill even if you do get COVID-19.
The post is more or less correct when it cites a survival rate of around 99.7%, although there is a good bit of debate around that exact number and the challenges in calculating an estimate. The figure would vary wildly -- depending on a person's age, underlying conditions, access to treatment and other factors -- but at its simplest level, the survival rate could be defined as the number of deaths divided by the number of confirmed COVID-19 cases.
As of December 23, 2020, there were 325,520 reported deaths and 18,407,728 confirmed cases in the United States, which translates into a survival rate of approximately 99.98%. Of course, it's worth noting, that even with such a seemingly high survival rate, close to 325,000 Americans have died from COVID-19. That count will surely grow in the coming months.
Back in March, Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Disease, cautioned against focusing on what may look like a low mortality rate. Testifying before Congress, he said:
If you count all the cases of minimally symptomatic or asymptomatic infection -- that probably brings the mortality rate down to somewhere around 1%, which means it is 10 times more lethal than the seasonal flu.
You can watch a clip from his testimony here: