This week the highly anticipated results of the major league baseball coronavirus prevalence study were released. The study led by Stanford physician Dr. Jay Bhattacharya sent testing kits to 5754 major league baseball employees who gave themselves pinprick to test for Covid-19 antibodies. The samples were then sent back to Stanford where they were tested and the results tabulated.
The results were not good for those hoping the United States had developed a path to herd immunity for coronavirus as these participants represented a nationwide sampling of individuals, most probably clustered in the major league markets. Of the 5754 participants, 60 tested positive for the Covid-19 antibody for an antibody prevalence rate of 0.7%. Recall that the concept of herd immunity dictates that individuals within a population become virtually immune to disease when over 30-40% (some epidemiologists say 70%) of the population has developed antibodies to the disease.
The concept implies that if no herd immunity exists for a population, then individuals have essentially no protection from acquiring that disease when mingling and interacting in the general population. Since no vaccine is likely to be available to the majority of the population until the second quarter of 2021 at the earliest, these results signify that the overwhelming majority of the population is vulnerable to acquiring Covid-19 in the next 12 months.
This study should be a wake-up call for those still sitting on their hands and waiting for the crisis to go away. This is the largest population surveillance study for Covid-19 in the US and implies that the overwhelming proportion of the population has not had the disease or has unsuitable antibodies to demonstrate immunity. Some might argue that too many false-negative might make the rate higher but others could equally argue that too many false-positives would make the actual rate even lower. The latter is actually more plausible due to cross-reactivity from a common cold coronavirus.
These results have major implications on how employers should think about having their employees return to work. While they can not hold off the work of their businesses in the near-term, they will need solutions to ensure that their employees are not becoming inundated with Covid-19 outbreaks while awaiting a vaccine. Employers should learn the importance of close symptom monitoring, developing a testing strategy, and finding the optimal contact tracing for their needs to prevent these outbreaks. A concerted effort by employers and employees alike will be necessary to develop a unified strategy about the businesses returning to work. Expecting worker to self-report possible Covid-19 symptoms without formalized symptom monitoring and guidelines around quarantines is likely to result in disaster for the businesses and the community. Due to innovations and tools in the marketplace that were specifically designed for Covid-19 return to work initiatives, employers do not need to venture into this territory alone.