Facebook released its first county-by-county maps of the U.S. on Monday showing the prevalence of self-reported COVID-19 symptoms based on data it has collected.
The maps, which will be updated daily, are meant to help health officials allocate resources and decide where parts of society can be reopened.
They use information from a voluntary survey Facebook has been prompting users to take. The survey, operated by the Carnegie Mellon University Delphi Research Center, is designed to help health researchers identify COVID-19 hot spots earlier.
Facebook CEO Mark Zuckerberg said the goal is to give state officials a sense of where they may need to direct resources, such as personal protective equipment, or PPE.
"Overall, since experiencing symptoms is a precursor to going to the hospital or becoming more seriously ill, these maps could be an important tool for governments and public health officials to make decisions on how to allocate scarce resources like ventilators and PPE, and eventually when it's safe to start re-opening society," Zuckerberg said.
The data doesn't include individual people's specific movements, and the survey, which is used to generate the maps, is something people must opt in to. Facebook plans to start offering the surveys internationally and will be releasing reports on the global prevalence of the disease.
"I think providing aggregate data to governments and health officials is one of the most important tools tech companies can provide," Zuckerberg said.
The maps add to tech companies' growing efforts to use their vast networks and data-collection tools to help provide a clearer picture of the outbreak and possibly create systems that will help states ease lockdowns. Apple and Google have begun building a system for smartphone-based contract tracing.
Instagram co-founders Kevin Systrom and Mike Krieger, who left Facebook in 2018, launched a website last week to track how COVID-19 is spreading in each state in real time. The site, RT.live, uses a metric called an effective reproduction number, which measures the average number of people who get the virus from one infected person.
Privacy advocates have warned that such efforts must not be taken lightly.
The announcement comes after the White House and the Centers for Disease Control and Prevention asked tech companies like Facebook, Google and Apple for greater access to Americans' location data in March to fight the spread of coronavirus.
Officials hoped to use the anonymous, aggregated data to track the virus' spread, a system called syndromic surveillance.
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Researchers have already been using Facebook's maps showing population movement, which are created using the social media company's access to aggregate location data.
The maps are meant to help researchers understand the spread of the disease and how it's affected by population patterns. They don't show individual patterns, just information at the city or county levels.
Facebook revealed three new tools in early April: co-location maps, which show the chances that people in one area will come into contact with people in another; movement range trends, which show regionally whether people are staying near their homes or visiting lots of parts of town; and a social connectedness index, which shows friendships across states and countries.