The American people, along with the rest of the world, are placing their hopes of defeating Covid-19 and ending this pandemic on a vaccine. There are multiple trials occurring around the world all at different stages, and while a safe and effective vaccine is top priority, time is also a factor considering this virus is continuing to infect and kill people.
Clinical vaccine trials are mainly meant to show whether a Covid-19 vaccine candidate will prevent any symptoms of the disease. The trials typically study between 30,000 to 60,000 volunteers, and some scientists are worried that the time spent on these trials will be too brief and too small to prove if the vaccine can actually prevent individuals from being hospitalized and dying, instead of just preventing a sore throat.
The United States specifically should wait for the most optimal vaccine to be on the international market, according to Dr. William Schaffner, a professor of preventive medicine and health policy at Vanderbilt University Medical Center.
“There’s a tension between getting every piece of information and getting a vaccine out in time to save lives. Would we like to know if the vaccine reduces illness or mortality? Of course. But there is a real time pressure. This is a pandemic. It’s explosive.”
The US Food and Drug Administration (FDA) held a public meeting this Thursday to discuss how rigorously Covid-19 vaccine candidates would need to be tested before the US considered them safe enough for distribution. “Simply preventing mild cases is not enough and may not justify the risks associated with vaccination,” said Peter Doshi, an associate professor at the University of Maryland School of Pharmacy.
On the other hand researchers also know that vaccines that prevent mild versions of a disease typically prevent the more severe version of the disease as well, so there are still good reasons to focus on studies involving milder cases of Covid-19. For example, according to Doshi, the original trials for a measles vaccine showed that it only prevented the virus itself, but not hospitalizations or deaths. Later studies, however, showed that the vaccine drastically reduced mortality, and according to the World Health Organization worldwide deaths from the measles fell by 73% in between 2000 and 2018 due to vaccines.
In general, proving a vaccine can prevent severe illness and death is much harder than showing it can protect against mild illness, because hospitalizations and deaths are more rare. Individuals who volunteer for vaccine trials are also typically on the healthier side.
“We’re probably not going to have the perfect vaccine. But I do think we’re likely to have vaccines that, if we can show they’re safe, can put an inflection point on this pandemic. … I think it’s still important to have a vaccine that has some effect even on mild illness.”
As it currently stands the Covid-19 pandemic has infected 8.7 million people in the US alone, and the mortality rate is about .6%. Leading scientists believe that the ideal vaccine will provide a sterilizing immunity front he virus. This would mean that the injection would prevent all symptoms of Covid-19 as well as secondary infections that could typically occur from the virus. Trials are projected to grow almost 10 times the sizes they are now as the months progress, and like any vaccine, the world won’t truly know how well it works until it’s actually here.
Eric Mastrota is a Contributing Editor at The National Digest based in New York. A graduate of SUNY New Paltz, he reports on world news, culture, and lifestyle. You can reach him at firstname.lastname@example.org.