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Contact tracing with smartphones

Study after study shows that contact tracing works to prevent new infections. It can be even more effective with new technology.

Research from the UK presented in Nature found that cases could decline if more people started using a mobile exposure notification app.

California launched CA Notify, a smartphone-based exposure notification program, in partnership with Google and Apple. The app has been activated by 10.5 million Californians -- less than 30% of the 39.5 million population -- and over 116,000 users visited the CA Notify website after receiving an exposure notification, according to the state's department of health.

\"These apps are most effective when there's very high utilization,\" Boyette said, such as among the closed environment of a college campus.

Boyette also warned that over-reliance on these smartphone applications may leave some people out or give false sense of security in low-use settings.

New research also indicates that current exposure notification apps might not be helpful for people who don't speak English, may be overly complicated, and don't always link to a testing site.

The contact tracing workforce

The White House recently announced that $7.4 billion will be invested in public health workers for pandemic preparedness and response.

Many public health departments now employ thousands of contact tracers in jobs they created during the early months of the pandemic. But as COVID-19 cases continue to decline, some have questioned whether those jobs are here to stay.

\"PHOTO:
Lindsey Nicholson/Education Images/Universal Images Group via Getty Images, FILE
PHOTO: Ambulnz, mobile Covid 19 testing van is set up in Kissena Park, Flushing Queens, New York.
>

Current contact tracing capacity may be more than needed because cases are lower, but that the same workforce could be used to improve overall health in their communities, said Dr. Josh Sharfstein, vice dean for public health practice and community engagement at Johns Hopkins Bloomberg School of Public Health.

According to Long, NYC plans to use its 4,000 contact tracers to establish a NYC Public Health Core to improve public health permanently and sustainably.

Public health experts agree that contact tracing can prevent the past from repeating itself. And Boyette is hopeful, telling ABC News the U.S. could be the next New Zealand or Australia.

\"They've been able to keep their numbers totally under control with contact tracing and supportive isolation and quarantine,\" she said, \"and I think this is our shot to get us across the finish line.\"

Dr. Jade A Cobern, pediatric resident in Baltimore entering the field of preventive medicine, is a contributor to ABC News Medical Unit.

Dr. Jay Bhatt is an internal medicine physician, an instructor at the University of Illinois School of Public Health and an ABC News contributor.

John Brownstein, Ph.D, is an ABC News contributor. He's also the chief innovation officer at Boston Children's Hospital and a professor at Harvard Medical School.

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