People may have to settle with illness-preventing vaccines, initially
Speaking to Bloomberg, several experts suggested that the goal of all ongoing efforts is to develop a shot that could prime the immune system to block the entry of the coronavirus, but the version we will get in the early stages might not do that.
Instead, it may just control the virus's spread in the body, thereby helping only the severe cases.
The early illness-preventing version of the vaccine could help countries open up, rebuild their economies, and then be followed up with a stronger, more effective shot capable of completely blocking out the virus.
"That's just practicality," Michael Kinch, a drug development expert at Washington University said, adding that "we may follow those up with more-perfect. But, there will never be a truly perfect vaccine."
"Vaccines need to protect against disease, not necessarily infection," Dennis Burton, a vaccine researcher at Scripps Research, said, echoing the same notion suggested by Kinch.
Notably, vaccines prevent up to 3 million deaths from infectious diseases every year but there are hardly any that are 100% effective. This is why people who get measles vaccine can develop a mild form of the disease.
To note, the FDA is also ready to consider vaccines that prevent illness from the novel coronavirus, not infection.
"We would potentially consider an indication related to prevention of severe disease, provided available data support the benefits of vaccination," FDA spokesman Michael Felberbaum told Bloomberg. "For licensure, we would not require that a vaccine protects against infection."
If a vaccine capable of preventing severe COVID-19, and not infection from the novel coronavirus, is developed and approved, cases of asymptomatic transmission could increase.
We already know that the disease can spread from asymptomatic individuals, and in that scenario, infected but vaccinated people could spread the virus without knowing, creating serious health problems for those who are yet to receive the vaccine.