With coronavirus hospitalizations largely on the decline nationally, a majority of states are eyeing the potential to enter a contact tracing phase once the numbers are low enough to realistically allow it.

Dr. Howard Forman, professor of radiology, economics, public health, and management at Yale University, told Yahoo Finance that contact tracing is a very effective tool. However, it’s only useful “at the very beginning and at the end of an outbreak,” he said. When the country is still largely in a massive outbreak — with a death toll surpassing 100,000 — it’s impossible to do.

But states, counties and cities are already hiring. And with more than 38 million newly unemployed individuals over the past nine weeks, there is a readily available workforce, experts say, to build a contact tracing army throughout the country.

But whether tracers will be a volunteer army or paid is still a question. The National Association of County and City Health Officials has estimated $3.7 billion is needed in emergency supplemental funding to local, state, territorial, tribal, and federal public health agencies to support a force of at least 100,000 contact tracers.

How will it work?

The Centers for Disease Control and Prevention (CDC) has outlined the core principles and requirements of a good tracing strategy, but specific federal action is unclear.

And how to train these individuals hasn’t been standardized— while it doesn’t require advanced technical skills, contact tracing does require training.

One early entrant to the game is the Johns Hopkins University’s Bloomberg School of Public Health. In collaboration with New York — and soon other local and state governments through their public health departments— the school is offering a free Coursera training class that governments are using to certify contract tracers.

The five-hour course is free, with a coupon code for the certification at the end. State and local governments are working to either automatically obtain, or require proof of, the certificate in order to move forward in hiring qualified candidates, according to Dr. Joshua Sharfstein, vice dean for public health practice and community engagement at the university.

The course has been viewed more than 21 million times, and more than 240,000 individuals are already enrolled, according to the site.

And the school is working on translations into other languages, after receiving multiple requests. Spanish will be the first, Sharfstein said.

The school has had to take on the role of providing this course due to a lack of leadership at the federal level, he said.

“It’s pretty unfortunate that the CDC hasn’t had a more prominent role” and that messaging is “inconsistent,” Sharfstein said. “The federal government hasn’t taken on the role expected in a crisis of this magnitude.”

Dr. Rob Davidson, an emergency physician in Grand Rapids, Mich., told Yahoo Finance that there are also discrepancies on what is considered a “contact” for the tracing.

During the HIV outbreak, for example, science provided a clear route of transmission. But for the coronavirus, a lot is still being learned about the highly transmissible disease.

“The reality of where they set the bar in terms of who is a contact is going to depend on resources,” Davidson said, including the availability of testing equipment to use on identified contacts.

But the clinical world can also help, as they are likely the first official interactions for some patients and are used to building trust with patients in short periods of time.

In the emergency room, the key goal will be convincing individuals to surrender “privacy for sake of public good is critical,” he said.

Outside of the hospitals and doctor’s offices, finding potential contacts will be harder. That’s where tracking apps, which have seen widespread adoption in other countries, could play a role, but they are unlikely to become a reality in the U.S. amid privacy concerns.

“I don’t think that’s ever going to come to pass here on a wide scale,” Davidson said.

Anjalee Khemlani is a reporter at Yahoo Finance. Follow her on Twitter: @AnjKhem

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