The NBA bubble is a grand experiment in epidemiology
We’ll see how technology, policy and human behavior influence an epidemic — and what we can do to stop it
The NBA bubble is maybe the greatest public demonstration of a space where the science of epidemiology is as central to operations as the financial office.
As the United States continues to deal with the consequences of the largest pandemic in a century with roughly 4.25 million cases and nearly 150,000 deaths as of July 28, the NBA bubble is an important moment in modern epidemiology. It is a grand experiment in how technology, policy and human behavior influence an epidemic. And what we can do to stop it.
“COVID-19 strikes as a protean disease, continuing to surprise and amaze even the most seasoned clinicians by its varied manifestations,” said Dr. Andre Matthews, an assistant professor in the Department of Emergency Medicine at the Emory University School of Medicine. “A consensus taken amongst medical practitioners may very well declare COVID-19 the ‘greatest masquerader’ that medicine has ever seen.”
The science of epidemiology has done wonders for society, greatly improved the quality of life for billions of people and saved countless numbers of lives. For example, epidemiologists helped limit the spread of the 2014 Ebola epidemic, and have informed practices that contributed to declining rates of malaria around the world. Epidemiologists can track an outbreak of cholera, a contaminated water supply, or help to understand the spread of the mumps virus on a United States warship.
The NBA bubble refers to the tightly controlled setting where players live, practice and play in order to conclude the 2019-20 season. The players have been confined to a space resembling a luxury boarding school, with proctors and chaperones and rules. It contains quirky details: The teams with the eight best records stay at the newest of the hotels, the Gran Destino Tower in Orlando, Florida, while other teams stay at older hotels. Players are discouraged from spitting and licking their hands. Biometric devices are being used to monitor vital signs. No guests are allowed inside a player’s hotel room.
There are lots of rules. The policies governing the entry into and exit from the bubble are strictly enforced. Anyone entering the bubble (players, personnel or staff) is required to quarantine for up to 48 hours until they register two negative COVID-19 tests. Anyone who leaves the bubble must quarantine upon their return (for as long as 10 days) and will need to register two negative tests, as well as an antibody test. Face masks are a requirement in any common settings.
The policies were developed as a collaborative endeavor between a range of experts, including epidemiologists who understand the latest science behind the spread of the coronavirus. These experts helped to create a set of policies that are based on interventions — the wearing of masks, social distancing, frequent testing — that have demonstrated their effectiveness in minimizing the spread of the coronavirus in many settings. But the NBA is constantly reevaluating and keeping up with the latest information on COVID-19 epidemiology so that the league can implement changes to the policy if necessary.
What makes epidemiology challenging in practice is the types of data that it often requires: Large data sets containing information on collections of people, their disease status and other information about them (e.g., age, sex, ethnicity, residence, etc.). And because epidemics happen in the real world and not in the laboratory, ideal experiments can be hard to come by.
Epidemiology can thrive on well-organized large experiments in existence, situations where groups of people are carefully studied for periods of time so we can understand how a disease happens and why it occurs in some populations. Famous examples include the Framingham Heart Study that has monitored cardiovascular health for several generations, and the Nurses’ Health Study, which has focused on factors contributing to chronic disease in women.
The NBA bubble carries several features of a great epidemiology experiment that may facilitate a better understanding of how the coronavirus is spread:
Testing every day. One of the great barriers to a sophisticated understanding of COVID-19 has been the fact that tests have not been readily available. Early in the United States outbreak, individuals suspected of having the disease struggled to receive diagnoses. As testing will occur daily in the bubble, the NBA will be in the unique position of knowing the COVID-19 status of everyone who lives in the bubble. This will allow for rapid intervention, starting with quarantine.
Knowledge of all subjects. The NBA bubble is a rare setting where one can know a lot about the individuals in a physical space. This level of surveillance is uncomfortable to some, but in the case of an outbreak, detailed information on the individuals can be crucial. For example, some have begun to speculate that the widespread differences in the experience of disease between individuals may have a genetic component. That is, some individuals may carry a mutation that may make them more likely to experience a serious disease. Because the NBA bubble isn’t inhabited by random individuals, it may be an opportunity to learn more about why some people have mild cases of the disease. This may include host genetics, or diet, preexisting conditions, or past medical history. While the NBA bubble will be dominated by high-performing athletes between the ages of 20 and 35, it still contains a diversity of players, coaches and staff that also span the age spectrum. Variation is an important feature, as it may help experts identify patterns.
Ideal data for contact tracing. “Contact tracing” has emerged as one of the buzz phrases surrounding COVID-19. It refers to a public health practice of informing the close contacts of an individual who tests positive that they might have been exposed to the disease, and should enter quarantine or undergo immediate testing. It is a tried and true method that has been used for decades to track epidemics ranging from Ebola to outbreaks of sexually transmitted diseases. It works best when it is widely adopted, and when professional contact tracers have detailed information on everyone that an individual who tested positive was close to. The NBA bubble offers a tremendous opportunity for accurate contact tracing, as many contact events will be televised. For example, not only would experts have access to where a player who tests positive in the bubble is residing (e.g., which hotel, and which room), they’d be able to study their physical contact patterns with players on another team.
With all of these features, what might we learn? The hypotheticals are too many to consider: Perhaps some teams will have cases, which will allow us to understand when they were infected, whom they infected, where they were when they were infected, how much time individuals spent with each other that caused an infection.
We may learn that the ventilation in some hotels might be superior, which explains why there were fewer transmission events in that hotel, relative to the others. Will guarding another player in the paint be associated with a higher probability of transmission than with guarding on the perimeter? Questions like this might be answerable in the NBA bubble.
The hope is that there are no outbreaks, and that the NBA season goes on without a hitch, unlike in Major League Baseball. While this outcome would be the least eventful, and the one that offered the fewest opportunities to learn about the spread of the coronavirus, it may also be the most telling: No events would tell us that the bubble was a success, affirming the practices implemented by the league to promote safety.
And in many ways, this lesson would be the greatest of them all: In a dark summer, when COVID-19 cases continue to climb around the country, maybe the NBA will remind us that the pandemic is conquerable when we follow the science.