COVID-19 Vaccines: Not A Panacea

[E]ven after more people get the shots, we’ll still have to wear masks and stay a respectful six feet apart from each other. [...] 

First, there’s the question of efficacy. Yes, Moderna and Pfizer reported that their shots are 94.5% and 95% effective, respectively. But that efficacy refers to the vaccines’ ability to protect against COVID-19 disease—and not necessarily against infection with the virus. Both of the rigorous trials to test the vaccines were designed to measure COVID-19 illness—trial volunteers were randomly given either the vaccine or a placebo, and then asked to report any symptoms of COVID-19 they experienced, such as fever, cough, shortness of breath or muscle aches. The study researchers then determined whether or not to test them. If people tested positive, they were logged as a confirmed COVID-19 case, and the researchers then looked at the group of COVID-19 cases and compared how many people had been vaccinated versus how many had gotten placebo. The effectiveness measured whether these people went on to develop more symptoms of COVID-19. 

That means that people who are vaccinated are not necessarily immune to getting infected; but they are more likely to experience fewer symptoms and not get as sick as those who aren’t vaccinated. 

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[B]ecause the vaccines do not necessarily protect against infection, that means that public health measures such as wearing masks, social distancing and avoiding indoor gatherings are still critical to containing the virus. 

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[T]he ultimate goal in controlling the pandemic, herd immunity, likely won’t happen until well into next year, when enough people are vaccinated and can ward off serious illness. “Not until a substantial proportion of the population is vaccinated, and the caseload has dropped to very low levels, will we be able to breathe (without a mask) a sigh of relief,” says Emanuel Goldman, professor of microbiology at Rutgers University. And even then, he points out, researchers will have to remain vigilant about tracking any changes in the virus as it finds fewer and fewer welcoming hosts. “The virus might have other ideas and try to change in a way that makes the vaccine less effective.” 

Only by vaccinating millions of people, and monitoring how their immune systems react, will experts get a better handle on what it takes to extinguish COVID-19 or at least make it much more difficult for it to spread….