Mayor Marty Walsh said in a press conference Monday that Boston has seen a 44 percent increase in coronavirus testing since last week and that the city will have 19 testing sites open to the general population by the end of the week. The ultimate goal, he said, is universal testing.

Walsh said that of the 28,000 people — four percent of the city’s general population — tested, 32 percent tested positive for the virus that causes COVID-19.

Walsh added that Boston is offering universal testing to the city’s homeless population, and as of Monday, 1,800 homeless individuals had been tested. About 33 percent have tested positive, and two have died as a result of the pandemic.

Walsh also urged city residents to continue to exercise caution when out in public, saying the city is not yet ready to reopen.

“We’re planning for what a reopening phase will look like, but we’re not ready,” he said. “We all need to stay the course right now.”

The mayor added that the city was continuing antibody testing and would be releasing that data to the public for analysis, though he did not specify when.

He also discussed efforts over the weekend to distribute over 70,000 booklets in seven languages with advice on coping with the dangers of a COVID-19 world.

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