The race to a COVID-19 vaccine requires a pledge for safety and efficacy
A worldwide race is on to make an effective vaccine to protect against the SARS-CoV-2 virus that emerged at the end of 2019 and causes COVID-19. At present, nearly 200 different vaccines are being developed, using protocols that are well proven in previous vaccines as well as protocols that have never been successfully used in the production of a vaccine. While a vaccine is the best hope to control the COVID-19 pandemic, it is critical that safeguards not be shortchanged for speed and that the process benefits from a collaborative global effort.
The development of a new vaccine is a painstaking process. Each vaccine target must be carefully studied for its potential for vaccine development. Once the vaccine is developed, it must pass experimental benchmarks in animals and clinical trials in healthy humans to ensure vaccine safety and efficacy; these safeguards are critical and usually take years.
But as the COVID-19 pandemic proceeds virtually unchecked in the U.S., the president has proposed “Operation Warp Speed” to develop a vaccine by the end of the year and is fixated on introducing a vaccine, proven or not, before election day.
The FDA, the federal agency that should safeguard us by approving only a properly tested and validated vaccine, may authorize a vaccine on only interim test data, forgoing complete safety and efficacy studies and bowing to political pressure. In response to growing concerns, the FDA has vowed to make decisions based on data.
A vaccine should pose risk to only a tiny proportion of people, those who may react adversely due to rare genetics or physiology. In 1955 Cutter Labs in Berkley produced batches of polio vaccine that were inadequately prepared and tested, leaving live polio virus in the vaccine. The contaminated vaccine caused many children and adults to suffer from debilitating paralysis and death. Paul Offit argues in his 2005 book, The Cutter Incident: How America’s First Polio Vaccine Led to the Growing Vaccine Crisis, that this incident was the beginning of vaccine hesitancy in the U.S.
The solace that safety and efficacy will not be shortchanged comes from pushback by pharmaceutical companies, who have issued a pledge that they will not release a vaccine for approval until it has met safety and efficacy standards. This pledge is proposed by competing pharmaceutical companies to resist pressure from the Trump administration, which has stoked public mistrust of the process and political influences on it. Three vaccines are currently in phase III trials, the final phase of testing. Despite promises by the president, these trials are unlikely to be completed by November.
The goal of the vaccine is to establish herd immunity, where >60 percent of the population has lasting immunity, such that the number of susceptible individuals is so low and dispersed in the general population that the virus cannot maintain itself in the population.
While herd immunity can also be established naturally by letting the infection spread unfettered to about two-thirds of the population, this would result in 215.6 million people infected in the U.S. Of these, many will have long-lasting consequences of the infection and between 650,000 and 2,000,000 will die, assuming a 0.3 – 1 percent death rate. A vaccine provides a safer route to elicit long-term immunity that would last years to decades and eliminates the morbidity and mortality of natural infection.
Beyond the logistics of manufacturing billions of doses of a new SARS-CoV-2 vaccine, assuring efficacy and safety requires phase III clinical trials involving thousands of healthy volunteers in addition to the laboratory validations. A prematurely presented SARS-CoV-2 vaccine that comes with adverse effects would set back vaccine research for many years, increasing distrust and vaccine hesitancy.
Heavily investing in the fastest vaccine to market may not result in the most effective vaccine. Whether or not a SARS-CoV-2 vaccine can provide long-term immunity (with or without boosting) remains unclear. SARS-CoV-2 was discovered only nine months ago and time is revealing unexpected biology and pathogenesis. Quality virologic and clinical studies are the cornerstones of vaccine development, and these have only just begun.
Attaining a safe, ethically developed, and effective vaccine requires organized worldwide cooperation between nations and open collaboration of many scientists and clinicians, sharing data, repeating experiments and conducting large clinical trials. Yet the Trump administration has said that it will not enter into a global effort to develop, manufacture and equitably distribute a SARS CoV-2 vaccine.
COVID-19 is a global problem. Thus vaccine nationalism is inappropriate, and America First could become America Last. Attaining a safe and effective SARS-CoV-2 vaccine must be a victory for the entire world. As we have witnessed, viruses have no borders. As we rush toward that victory, we must work with global partners and, most importantly, take the necessary time to establish vaccine safety and efficacy.
James Alwine is a virologist and a fellow of the American Academy for Microbiology and of the American Association for the Advancement of Science. He is a professor emeritus at the University of Pennsylvania and a visiting professor at the University of Arizona. Felicia Goodrum Sterling is a virologist and a fellow of the American Academy for Microbiology. She is a professor and scientist at the University of Arizona.