The Australian government coronavirus tracking app "COVIDSafe" installed on a phone in Sydney, Australia, Monday. Photo: Mark Kolbe/Getty Images

Almost 2 million Australians have downloaded a coronavirus tracing app within hours of its release, Health Minister Greg Hunt announced Monday, as the country moves to ease restrictions.

The big picture: A top health official stressed at a briefing Sunday that the app is "only for one purpose, to help contact tracing," as the government seeks to get at least 40% of the population to use the app for it to be effective. Australia has reported just over 6,700 cases and 83 deaths from COVID-19. In the U.S., most people told a Kaiser Family Foundation poll they'd share their coronavirus test results with public health officials, but fewer would download an app that tracks who they come in contact with.

Go deeper: Americans' buy-in for smart phone app could be red flag for coronavirus contact-tracing

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Updated Aug 4, 2020 - Health

The states where face coverings are mandatory

Data: Compiled by Axios; Map: Danielle Alberti/Axios

Mississippi Gov. Tate Reeves issued a statewide mask mandate on Tuesday for people in public, as well as teachers and students going back to school.

The big picture: 34 states, in addition to the District of Columbia, have issued some form of a mask mandate as infections surge across the country.

Updated Aug 4, 2020 - Health

NYC health commissioner resigns in protest of De Blasio's coronavirus response

Dr. Oxiris Barbot attends a Mayor bill de Blasio briefing on August 3. Photo: Lev Radin/Pacific Press/LightRocket via Getty Images

New York City health commissioner Oxiris Barbot resigned Tuesday, citing "deep disappointment" that Mayor Bill de Blasio did not use the full extent of available disease control expertise to handle the pandemic, the New York Times reports.

Context: De Blasio has faced criticism from health officials for handing control of the city's army of coronavirus contract tracers to the public hospital system, rather than the health department, according to the Times. The health department conducted contact tracing at the start of the outbreak and has decades of experience doing the same for diseases like tuberculosis, HIV and Ebola.

Updated 5 hours ago - Health

World coronavirus updates

Data: The Center for Systems Science and Engineering at Johns Hopkins; Map: Axios Visuals

Spain's government announced on Friday that it will shut down nightclubs, ban public smoking and restrict nursing home visits as coronavirus cases climb in the country.

By the numbers: Over 761,000 people have died of the novel coronavirus globally and another 21 million have tested positive, per Johns Hopkins University data. More than 13 million have recovered from the virus.