Contact Tracing Deployed In Effort To Fight Spread Of Coronavirus

Massachusetts has the third-most cases of the coronavirus in the U.S. and the death toll there has nearly doubled in the past week. The hot spot is the first state to launch a large-scale program to track down people who've been exposed to COVID-19.

It's called contact tracing and the state is deploying an army of disease detectives.

Dean Xerras took CBS News inside a COVID-19 hotel for the most vulnerable. Wendy Rosales found out over the phone last week she was exposed to COVID-19. After testing positive, she's now quarantined.

"I thought was I am going to die," Rosales told CBS News in Spanish. "I was really afraid."

The 35-year-old wife and mother of two is from Chelsea, north of Boston, a densely populated immigrant area with the highest infection rate in the state.

Krysta Cass is a "contact tracer" working from her Boston apartment. She calls at least 20 people a day who recently tested positive for COVID-19 and then anyone they may have exposed.

"There are some people that had no idea they came in contact with someone who was positive," Cass explained.

Massachusetts has invested $44 million in disease detectives, who will reach at least 120,000 close contacts — all of it critical to bending the curve, according to Partners in Health.

Joia Mukherjee is the chief medical officer for the group leading the effort. Partners in Health have been using contact tracing for decades to fight outbreaks from Ebola to AIDS.

"Of course we have to do whatever it takes," Mukherjee said. "And we believe that, you know, this kind of approach also could create millions of jobs to put people to work fighting the epidemic. Make a public health corps."