My scientific colleagues and I are failing miserably in our responsibility to the public.
Our federal government, as well as many states, have demonstrated an appalling lack of leadership in coping with COVID-19. We lack reliable information, consistent messaging, and proper examples about preventing infection; this is not news. When government officials have made the wrong decisions, it was generally due to an epic failure to take the situation seriously. They were not being cautious enough. Unfortunately, scientists (and I count myself among them) are failing as well, but for the opposite reason. The scientific community, through an over-abundance of caution, has not consistently provided clarity to an understandably worried and confused public.
The Food and Drug Administration’s recent guidance that the approval of a COVID-19 vaccine will be contingent on showing that it can “prevent disease or decrease its severity in at least 50 percent of people who are vaccinated” brings to mind a particularly egregious example — what antibodies mean and what vaccines promise. The New York Times reported in June (based on interviews with scientists) that “It is simply too early to know if the presence of antibodies confers immunity…“ A confusing assertion was made in the Financial Times in May by the World Health Organization, which said there was “no evidence” that [antibody] tests could “show that an individual is immune or protected from reinfection.” The WHO has subsequently hedged its bet, suggesting “We expect that most people who are infected with Covid-19 will develop an antibody response that will provide some level of protection,” while the New York Times reports that experts now suggest that reinfection with COVID-19 may be “unlikely.” This equivocation not only confuses the public, but may lead them to believe that we don’t know what we are talking about.
This is just crazy, and it doesn’t take into consideration what we do know from more than two centuries of study, which is that recovery from viral infections generates protective immunity. This is classically illustrated by work from the Danish physician Peter Panum in his study of a measles outbreak in 1846 in the Faroe Islands. He noted that most islanders who had been born after 1781, the date of the previous measles epidemic, became infected with the disease. However, none of the 98 residents who had survived the 1781 epidemic became ill in 1846. They had long-lasting viral immunity. We now understand this is the result of different cells in the immune system working together to, among other things, produce antibodies. While it is technically correct to say that we don’t know if antibodies will protect us from coronavirus infection, the likelihood is overwhelming that they will. However, since not every viral infection leads to the type of robust immunity that measles confers, the one thing we truly don’t know yet, is how long those antibodies, and hence the protection, will last.
Moreover, if antibodies don’t protect us from infection, why would we expect that vaccines would? I am not aware of any viruses for which vaccines provide effective immunity, but recovery from the infection itself does not. It’s worth considering what vaccines are, which is a way to deliver a version of the virus, or pieces of the virus, which are sufficient to generate protection against infection. One of the earliest examples of this was the late 18th-century introduction of using cowpox virus (which generally causes mild symptoms) to induce immunity to its close relative smallpox (a far more severe infection). Viruses hadn’t been discovered yet, but this procedure was termed vaccination by Edward Jenner, from the Latin word for cow, vacca. The idea that vaccines will work to protect us when infection does not is counterintuitive to our understanding of the immune system.
So why are so few of us communicating what we know? As scientists, we are trained to be cautious in our conclusions, and to never assert any facts that have not been conclusively proven by evidence. I fear that this training has gotten the better of us during this pandemic. Can I absolutely guarantee that antibodies as a result of infection will protect someone? Every rule can have exceptions, so I suppose I cannot. But I also cannot guarantee that the sun will rise tomorrow morning. Yet, we should plan our day around it nonetheless.
Dr. Laurence Turka is the chief scientific officer of Rubius Therapeutics, the Harold and Ellen Danser Professor (Emeritus) at Harvard Medical School, and deputy director of the Immune Tolerance Network.