This is how fast COVID-19 spreads through hospitals

While many of us have been able to ride out this pandemic from the safety of our homes, the world’s healthcare and hospital workers continue to selflessly put themselves in harm’s way to treat patients and save lives. All of these professionals, from cleaning staff to physicians, are at risk of contracting COVID-19 each time they walk through their hospital’s doors. 

Due to COVID-19’s tendency to manifest itself asymptomatically in many carriers, it’s proven nearly impossible to track all the healthcare workers who have become infected with the coronavirus. In all likelihood, though, that number is very high. For example, a recent study out of Cambridge University in the UK estimates that up to 3% of NHS staff are working in hospitals right now while unknowingly contagious.

In the US, that percentage could be even higher. To try and get an idea of just how quickly COVID-19 (both asymptomatic and symptomatic) can spread through a confined hospital setting, researchers from Indiana University’s School of Medicine performed antibody tests on groups of patients, nurses, doctors, and staff within a local hospital’s pediatric dialysis unit. Predictably, yet no less disconcerting, the results paint a picture of a virus spreading in secret.

The use of antibody tests is an important aspect of this work; it allowed the researchers to identify people who never developed symptoms but were still contagious for at least some period while on the job.

“There are unique exposure challenges in dialysis units that limit social distancing efforts, including open bay formats and rotating nursing assignments,” says David Hains, MD, lead investigator on the study, in a university release. “Dialysis units find threat among many infectious diseases and COVID-19 is dangerous to patients receiving dialysis.”

Research from the coronavirus’ epicenter, Wuhan, China, had already indicated that dialysis units were particularly at risk, but this is the first study anywhere examining a pediatric dialysis area. It is also the first to test for antibodies, providing a much more complete analysis of the virus’ spread.

“Our study also highlights the importance of distancing and PPE,” Dr.Hains adds. “We saw a dramatic decrease in ‘new’ cases as we implemented more aggressive measures to protect our patients and staff. More studies to examine this are underway by several people here on campus.”

In all, four staff members, 11 nurses, and 10 doctors from the dialysis unit were tracked for the study in April. To start, all participants were tested for COVID-19 using PCR tests and showed no signs of the virus. Three weeks into the tracking period, however, 11 healthcare workers and three patients had tested positive for COVID-19 antibodies. While two study participants did have some respiratory symptoms between day zero and day seven of the study, no one else developed any symptoms between day seven and day 21.

“This study found a high occurrence of COVID-19 antibodies in individuals interacting in a pediatric dialysis unit. This high rate of occurrence suggests that more health care workers may be antibody-positive than would otherwise be expected,” Dr. Hains explains. “Testing for the presence of these antibodies can allow for strategically staffing the care of patients who have COVID-19, or who are suspected to be positive, with nurses and physicians who also have tested positive for these antibodies.”

One of the participants who tested positive for COVID-19 antibodies, a nurse showing no outward symptoms, took another PCR test which did reveal an active coronavirus infection. Thanks to the initial antibody test, Dr. Hains says his team was able to quickly act and isolate the nurse from other people.

“When she had a COVID-19 test, she was positive. That allowed us to rapidly quarantine her, which may have helped prevent the spread in our unit,” Dr. Hains comments. “I can see this being utilized in other healthcare settings or arenas where distancing is not easily done.”

The study’s authors plan to recreate their research in the near future. As Indiana, and many other states, begin to loosen social distancing rules, outbreaks in hospitals may become even more problematic. This study certainly doesn’t apply to only hospital workers, though; we all must remember anyone can be contagious regardless of whether or not they feel sick. 

The full study can be found here, published in JAMA.

John Anderer is a frequent contributor to Ladders News.