UCSF Grand Rounds: A contact tracing army, and dispatches from a New York hospital

The medical community is working furiously to develop measures that may become mainstream in a post-shelter-in-place world. Maybe Remdesivir, an anti-viral drug and possible treatment for COVID-19, will become a household name, and testing a frequent ritual. 

Without question, the practice of “contact tracing” will be a part of our new reality. 

That’s what Michael Reid, an infectious disease professor at Zuckerberg San Francisco General, explained during Thursday’s UC San Francisco medical Grand Rounds session.

“The question everyone is asking is, when can we move beyond shelter in place?” said Reid, who has been working with the San Francisco Department of Public Health to build and refine its contact tracing program. 

Once San Francisco confidently lowers its case count and has confidence in its hospital capacity, our health department will need a human “army” to trace all of the so-called “contacts” a COVID-19-positive person has potentially infected, he said. This not only slows transmission by having the infected self-isolate, but also allows health officials to move quickly to hospitalize people who need greater care.

A study in Shenzhen, China, Reid explained, found that contact tracing allowed health officials to isolate the potentially infected three days sooner than if they were using basic symptom surveillance. That’s because many people do not initially show symptoms or may not show symptoms at all. Twenty percent of the COVID-positive patients in the study were asymptomatic, and 30 percent did not have fevers. 

With all this in mind, Reid is helping San Francisco build a platoon of contact tracers. In Wuhan, China, the epicenter of the first outbreak, some 9,000 contact tracers were deployed to reach a population of 11 million people. In San Francisco, Reid said, we will need far fewer. “We need a workforce of 100 to 150 doing this or being available to do this,” he said, especially as shelter-in-place ends and our contacts begin to grow. 

An unlikely cast of characters has already emerged to aid in the current effort: San Francisco city attorneys, librarians, and other civil servants are now contact tracers. Right now, there are 105, including UCSF staff members and medical students. 

But contact tracing alone is “no silver bullet,” Reid said. “It only works as part of a sophisticated public health response,” meaning the resources need to be available to support and monitor those who have been isolated. 

Being asymptomatic and being immune 

Dr. Brian Schwartz, an infectious disease professor at UCSF, explained how people can be infected with COVID-19, show no symptoms for days — and still be highly contagious. Hence the importance of constant testing and contact tracing. 

He cited a study released last Friday that examined an outbreak at a skilled nursing facility in Seattle in late February. Forty-eight of 76 elderly residents tested positive during an investigation. Of those who tested positive, 27 initially showed no symptoms — yet, over time, 24 developed symptoms of the disease, and some died. The mortality rate at the facility was 26 percent.  

Some of the residents, he said, had been transmitting the disease an entire six days before showing symptoms, “suggesting that many, many days prior to developing symptoms … these patients are able to transmit infection.”

Accordingly, Schwartz’s colleagues — Drs. Diane Havlir, Monica Gandhi, and Deborah Yokoe — recommended in an article in the New England Journal of Medicine that skilled nursing facilities, as well as jails, homeless shelters, and enclosed mental health facilities, should receive constant testing and retesting. 

Separately, Schwartz noted that the odds were “likely” that the presence of antibodies in our blood — meaning you’ve already contracted the virus — is a sign of immunity. “But it is still unknown,” he said, as there are not enough data to support a conclusion. 

He added that it’s very likely that any immunity we may develop will be temporary. Immunity to other viruses in the coronavirus family has typically not lasted long, he said. 

Dispatch from New York

Amir Jaffer, the chief medical officer at the NewYork-Presbyterian Hospital in Queens, spoke of the pandemonium as his hospital became flooded with patients in March. The hospital’s first COVID-19 patient came on March 8. “I have to say, when we started to have the initial cases, we didn’t know what lay ahead of us,” he said. “We were really caught by surprise with the amount of surge that we had.” 

Indeed, the numbers mounted quickly. The hospital began seeing as many as 50 new patients a day. At its peak, the branch in Queens had 105 patients on ventilators, he said; right now there are still more than 90 on ventilators. (Compare that to the four patients on ventilators right now at UCSF’s hospital.) Entire sections of the hospital were transformed into intensive care units for COVID-19 patients, as it increased its capacity to 120 ICU beds while experiencing a dearth of staff to tend to them.  

“We were fighting on a daily basis,” he said. 

Despite the hospital’s best efforts, approximately 500 people of some 2,000 admissions have so far died of coronavirus infection at the hospital, he said. Some of his colleagues have died as well, he said. “We can’t forget the lives that have been lost to this ferocious virus.”