Most U.S. parents say it would be risky to send their children back to school in the fall — including a slim majority of Republicans and a staggering nine in 10 Black Americans — in this week's installment of the Axios-Ipsos Coronavirus Index, Axios' Margaret Talev reports.

Why it matters: President Trump and Education Secretary Betsy DeVos have threatened to withhold federal funds from schools that don't reopen. The new findings suggest that this pressure campaign could backfire with many of the voters to whom Trump is trying to appeal ahead of the election.

What they're saying: "Americans at this point, and parents more specifically, can't be force-fed policies that go against what they think," says Cliff Young, president of Ipsos U.S. Public Affairs.

• "You can't wish away or scare away a virus," Young says. "And right now, they're not feeling safe in putting their children back in school."
• "There's political risks as well — serious political risks for Trump and Republicans. Because even the Republican base sees a risk in putting kids back into the school in the fall."

Driving the news: Officials on Monday began announcing decisions impacting schools in some major metro areas, erring on the side of caution in response to health concerns and parents' anxieties.

• In California, school officials announced that public schools in Los Angeles and San Diego will hold online classes only.
• Gov. Andrew Cuomo said Monday that New York schools will open only if the daily infection rates in their region are below 5% over a 14-day average, and that "we're not going to use our children as guinea pigs."

Nearly two-thirds of Americans — and a noticeably increasing number of Republicans — say they’re wearing a face mask whenever they leave the house, according to the Axios-Ipsos Coronavirus Index.

Why it matters: A weakening partisan divide over masks, and a broad-based increase in the number of people wearing them, would be a welcome development as most of the country tries to beat back a rapidly growing outbreak, Axios' Sam Baker writes.

By the numbers: 62% of those surveyed said they're wearing a mask "all the time" when they leave the house — up from 53% when we asked the same question two weeks ago.

• The biggest jump was among Republicans: 45% say they’re wearing a mask all the time, up from 35% at the end of June.
• Even though it's narrowing, there’s still a big partisan divide: 95% of Democrats say they wear a mask some or all of the time outside the house, compared with 74% of Republicans.

Between the lines: These numbers may seem high — do two-thirds of the people you pass on the street have a mask on? But the fact that more people are claiming to wear them is at least a sign that masks are increasingly seen as important.

• Among people who said they wear a mask sometimes, 32% reported that they’ve been denied entry into an establishment because they weren’t wearing one, and 21% said someone else has told them to put one on.
• 15% said they’ve told someone else to put on a mask.

Houston Mayor Sylvester Turner tweeted on Monday that he has proposed a two-week citywide shutdown to Texas Gov. Greg Abbott as coronavirus infections and hospitalizations continue to surge.

Houston's coronavirus situation is "dire, and it's getting worse, seems like, every day," Harris Health System CEO and President Esmaeil Porsa said Monday on MSNBC's "Morning Joe."

California Gov. Gavin Newsom on Monday ordered indoor operations for restaurants, wineries, movie theaters and other family entertainment like zoos, museums and card rooms to cease immediately. Bars must also close entirely.

The U.S. budget deficit reached $864 billion in June as Congress allocated trillions to help cushion the damage from the coronavirus recession and massive job losses reduced tax revenues, the Treasury Department said in its latest monthly report.

Former White House chief of staff Mick Mulvaney wrote in a CNBC op-ed published Monday that if Congress seeks to pass another relief package, it should treat the economic crisis as "public-health driven" and avoid traditional fiscal measures like providing stimulus checks.

World Health Organization director-general Tedros Adhanom Ghebreyesus warned Monday that "there will be no return to the 'old normal' for the foreseeable future," but that there is a "roadmap" for struggling countries to get the virus under control.

Hong Kong Disneyland on Monday announced that it would close again on July 15, after reopening last month from a coronavirus-driven shutdown that began in January.

Roughly 5.4 million adults in the U.S. lost their health insurance from February to May after losing their jobs, according to a new estimate from Families USA, a group that favors the Affordable Care Act.

Why it matters: There are more adults under 65 without insurance in Southern states, which are the same states setting new records for single-day coronavirus infections along with rising hospitalizations, Axios' Orion Rummler writes.

What they found: 3.9 million adults lost health insurance over one year during the Great Recession, per Families USA's analysis. It only took four months in this current crisis for an estimated 5.4 million Americans to lose health insurance.

• More than 20% of adults in Georgia, Florida, South Carolina, North Carolina, Mississippi, Oklahoma and Texas were without insurance as of May.
• All of these states have set new records in the past two weeks for their highest number of coronavirus infections in a single day, per data from the COVID Tracking Project.
• 46% of adults who lost coverage due to the pandemic came from five states: Florida, New York, Texas, California and North Carolina.

The backdrop: 21 million Americans were unemployed in May, according to the Bureau of Labor Statistics' nonfarm payrolls report.

Testing buildings — not just people — could be an important way to stop the spread of the coronavirus, Axios' Joann Muller reports.

Why it matters: People won't feel safe returning to schools, offices, bars and restaurants unless they can be assured they won't be infected by coronavirus particles lingering in the air — or being pumped through the buildings' air ducts. One day, even office furniture lined with plants could be used to clean air in cubicles.

The big picture: Prodded by more than 200 scientists, the World Health Organization now acknowledges there is emerging evidence of airborne transmission in crowded or poorly ventilated settings.

• In Florida, Texas and other Sun Belt states, a dramatic rise in COVID-19 cases has been linked to air-conditioned bars, house parties and other large gatherings.
• The virus thrives indoors in both heated and cooled environments if the humidity is below 40%, scientists say.

Driving the news: New research from the University of Oregon, in partnership with the University of California-Davis, suggests heating, ventilation and air conditioning systems could be contributing to the spread of the disease in health care facilities.

• There are some fairly easy fixes, like installing more sophisticated air filters, drawing more fresh air into buildings and cranking up the humidity, which tends to kill the virus.
• But when it's extremely hot or cold outside, some of these measures could overwhelm HVAC systems, ventilation experts say.

Go deeper.

Quest Diagnostics said its average turnaround time for a COVID-19 test is now at "seven or more days," up from four to five days at the end of June.

• Its testing backlog is getting worse because of the high demand in parts of the country where infection is spreading, Axios' Bob Herman writes.

Why it matters: Long backlogs make testing less useful — public health officials need to know what their local situation is like now, not what it was like a week ago. Delays are especially problematic if people who are infected continue to go about their lives while they wait for their results.

Between the lines: Quest told investors Monday that its second-quarter revenue will be down 6%, hovering around $1.83 billion, as coronavirus testing has supplanted other, more lucrative tests that had to be put off.

• But Quest still expects to register a profit of at least $1.33 per share thanks to $65 million of government bailout funds and high volumes of COVID-19 tests.