Schools in Southern and Midwestern states are most at risk of coronavirus transmission, according to an analysis by Coders Against COVID that uses risk indicators developed by the Centers for Disease Control and Prevention.

The big picture: Thankfully, schools have not yet become coronavirus hotspots, the Washington Post reported this week, and rates of infection are lower than in the surrounding communities. But that doesn't mean schools are in the clear, especially heading into winter.

The risk of opening schools closely tracks the prevalence of the virus in that community.

• Yes, but: In some rural areas, where the population is small, it only takes a handful of cases to hit what the CDC has deemed a "moderate" risk level.

By the numbers: On Sept. 8, Missouri, Alabama, Oklahoma, South Carolina, Tennessee, Arkansas and Iowa had the highest average statewide transmission risks in the country, according to the Coders Against COVID analysis.

• Connecticut, D.C., New York, Massachusetts, New Hampshire, Maine and Vermont all had a transmission risk of 1, the lowest possible.

Iowa, Arkansas, Florida and Texas — all of which had relatively high risk scores — have ordered in-person instruction to be available part- or full-time, according to Education Week.

• D.C. schools have been ordered to do distance learning until November, and New York City has yet to open its schools after announcing its plans to do so.

What we're watching: Data reporting is inconsistent, but Arkansas, Mississippi, Texas and Tennessee have all already reported more than a thousand cases in K-12 schools, the NYT reported earlier this week.

• Many of the largest school districts still aren't open for in-person learning, and flu season is around the corner. But for now, schools have avoided some of the worst-case scenarios.

President Trump issued an executive order yesterday pledging to protect Americans with preexisting conditions — which is not only toothless but also is only necessary if a Trump-backed lawsuit successfully dismantles the Affordable Care Act.

• Executive orders such as this one "don’t have legal effect. They’re just internal memos with a fancy header. That’s all they are," tweeted Nick Bagley, a law professor at the University of Michigan.

Why it matters: The presidential election is a month and a half away, and Republicans learned the hard way in 2018 that threatening the ACA's preexisting conditions protections is politically perilous.

• But yesterday's executive order is yet another example of Trump's political gaslighting on the subject.
• Republicans have never come up with another way to offer the same level of protection the ACA does. If Trump succeeds in stripping the ACA's protections away, people with preexisting conditions would have every reason to worry about their coverage.

Trump also said that he'll be sending $200 prescription drug coupons to millions of Medicare beneficiaries “in the coming weeks,” which STAT describes as a "nakedly political ploy to curry favor with seniors who view drug prices as a priority."

• A White House spokesman told STAT that the money required to send these coupons would come from the savings generated by Trump's proposal to tie what the U.S. pays for drugs to what other countries pay — which is far from being actual policy.

Four vaccines for the novel coronavirus are now in late-stage testing in people in the United States. Here's where they stand.

The CDC forecasts that the U.S. will lose another 3,400 to 7,400 lives to COVID-19 by Oct. 17. That would bring the country's death toll from the virus to between 214,000 and 226,000.

New York Gov. Andrew Cuomo (D) said Thursday that the state will move forward with its own review process of coronavirus vaccines even if the Food and Drug Administration approves one or more for distribution and public use.

House Democrats are preparing a slimmed-down coronavirus relief proposal focused on unemployment and direct payments that would cost roughly $2.4 trillion.

The Pac-12, which includes universities in Arizona, California, Colorado, Oregon, Utah and Washington state, will play football starting Nov. 6, reversing its earlier decision to postpone the season because of the coronavirus pandemic.

The number of deaths from COVID-19 surpassed 980,000 worldwide on Thursday.

A global initiative to ensure equitable distribution of coronavirus vaccines now includes most of the world — but not the U.S., China or Russia, Axios' Dave Lawler reports.

The vaccine maker Novavax said it is entering the final stages of testing its vaccine in the United Kingdom and another major trial is scheduled to begin next month in the U.S., the New York Times reports.

How sick a person gets from a virus can depend on how much of the pathogen that person was exposed to and how much virus is replicating in their body — questions that are still open for the novel coronavirus, Axios' Alison Snyder and Eileen Drage O'Reilly report.

Why it matters: As people try to balance resuming parts of their daily lives with controlling their risk of COVID-19, understanding the role of viral load could help tailor public health measures and patient care.

How it works: Viral dose is how much virus someone is exposed to when they are infected. Viral load is the amount of virus produced in someone's body after they are infected.

• A higher infectious dose of a virus and a higher viral load are linked to more severe disease from influenza, poxviruses and other viruses.

For SARS-CoV-2, the virus that causes COVID-19, "there's accumulating data on both sides of the equation," Monica Gandhi, a professor of medicine and an infectious disease doctor at UCSF, tells Axios.

• Some researchers suggest a decline in death rate and the rise in asymptomatic cases in the U.S. this summer — both coming at a time when mask-wearing became more common — indicate reducing the dose of the virus may reduce the severity of disease.

Yes, but: Other studies have also found some people without symptoms can have viral loads similar to those with symptoms. And children, who tend to be spared severe COVID-19 complications, can carry as much or more of the virus in their upper respiratory tract.

Go deeper.

People in their 20s accounted for more than 20% of all COVID-19 cases between June and August, analysis from the CDC shows, bringing the median age of coronavirus patients to 37, down from 46 in the spring.

Why it matters: Young people are less vulnerable to serious illness, but they contributed to community spread over the summer, the analysis says — meaning they likely infected older, higher-risk people, especially in the South, Axios' Marisa Fernandez writes.

Meet Norman, who is a good boy and is also very ready for this unusual school year!

• "He's a rescue, he's 3 years old, and he's about 45 pounds larger and 2 ft taller than we were told he'd be, so breed is anyone's guess," his mom, Lindsay, writes.

And here's a bonus dog for the week, just because it's been an extra-long one. Meet Darla, who has a vest that is to be envied.

Keep sending your dogs!