with Paulina Firozi

The novel coronavirus is clearly deadlier than the seasonal flu, despite President Trump’s ongoing efforts to downplay its risks.

But how much more deadly? Figuring that out isn’t easy. 

That’s because the calculation involves an elusive number: the total people infected, not just those known to have tested positive. While testing has ramped up dramatically in the United States, researchers are still trying to figure out precisely how far and wide the virus has spread. 

To complicate matters, there's more than one way experts calculate fatality rates. The fatality rate would appear lower if deaths are measured against a projection of all estimated infections. If deaths are measured against only those with symptoms – a smaller group, especially since many with coronavirus are asymptomatic – the fatality rate appears higher.

“It’s confusing,” said Robin Patel, president of the American Society for Microbiology. “In many cases we use that term fatality rate, and it can mean a lot of different things.”

As infections and hospitalizations surge in the South and the West, it has further inflamed an already-heated debate over how deadly the virus is and whether widespread and economically harmful measures to stem it are justified.

Larry Levitt, executive vice president of the Kaiser Family Foundation:

The unresolved questions haven’t stopped Trump and others from claiming that risks from covid-19 are overblown.

Conservatives have latched on to the lag in deaths as coronavirus cases spike to claim the illness's lethality has been overstated. “What they’re not telling you is the death rate, radio host Rush Limbaugh said on his show Monday. “The death rate is falling. But you don’t know that because they are simply reporting this massive increase in cases.”

Trump has been making similar claims, as he tries to paint the country as post-pandemic and on the road to recovery.

The World Health Organization estimated the infection fatality rate for the first time last week.

WHO chief scientist Soumya Swaminathan said the rate is 0.6 percent. While that’s a small percentage, it could translate to 1.7 million deaths in the United States should every single person become infected.

But the general infection fatality rate isn’t necessarily helpful for officials and individuals trying to better grasp the virus’s threat. The risk varies widely by age and health status, with older people with preexisting health conditions at much greater risk of dying. For example, only 30 kids in the U.S. younger than age 15 have died of covid-19, out of 115,000 deaths tallied by the Centers for Disease Control and Prevention.

“We think about this as: ‘If any average person gets it, what is their chance of dying?’ ” Patel said. “Well, nobody is an average person, so that statistic is misleading.”

The CDC has focused on fatalities among only those with symptoms.

That approach can make the virus seem more deadly, because it involves a smaller pool of people.

The agency has said people who develop symptoms have a 0.4 percent risk of dying overall, although the agency hasn’t explained how it calculated that rate. It also provided age-based estimates, saying that those over age 65 have a 1.3 percent chance of dying while those under age 50 have only a 0.05 chance of dying.

But the CDC says the fatality rate drops to 0.26 percent overall if it’s measured against all infections — an estimate considerably lower than the WHO’s estimate. 

“It’s confusing because there are different denominators, different rates,” said Anirban Basu, professor of health economics at the University of Washington. “So it’s important to lay out the different subgroups we are talking about.”

The fatality rate also depends on knowing the total number of deaths, which may be underestimated in some places. 

Media reports have chronicled a rise in the number of patients dying at home in New York City and Houston amid case surges before they are ever tested for the coronavirus.

It is also hard to estimate the true fatality rate because many people aren’t tested.

Calculating the infection fatality rate requires researchers to make an educated guess about how widely the virus has been circulating. Thirty-five percent to 45 percent of cases may not result in symptoms, complicating the task.

Neerja Sood, a professor of health policy at the University of Southern California, estimates the infection fatality rate is probably 0.13 percent for people outside nursing homes and 0.26 percent when people in nursing homes are included. That estimate is based on a survey of Los Angeles County residents who were tested for antibodies to the virus. 

But Sood told my colleague Joel Achenbach the rate could easily change if any of the numbers used to calculate it are off.

“Depending on how you make the assumptions, you can get different answers for the infection fatality rate,” Sood told Joel.

The fatality rate looks closer to 5 percent if deaths are measured only against known cases.

Basu said this “case fatality rate” is typically between 4 percent and 7 percent in most countries.

In the United States, it’s 4.2 percent, according to the statistics website Worldometer. That’s the total number of people who have died of the virus divided by the total number of people who tested positive for it. 

Different countries have reported vastly different case fatality rates, probably reflecting differences in the age of their population, access to medical treatment and testing rates. Based on the Worldometer figures, the case fatality rate is 3.9 percent in Brazil, 4.6 percent in Germany, 9.5 percent in Spain and 15.5 percent in the United Kingdom.

But when it comes to people who actually develop symptoms, far fewer of them — about 1.3 percent — actually die, according to Basu’s own research

That’s much less lethal than what the case fatality rates suggest — but still far more lethal than the seasonal flu, which kills only about 0.1 percent of those who fall sick with it.

Ahh, oof and ouch

AHH: WHO acknowledges droplets carrying coronavirus may linger in the air, especially indoors with poor ventilation.

The U.N. agency updated its description of how the coronavirus spreads, a move that comes amid pressure from the scientific community. More than 200 scientists from more than 30 countries urged the United Nations just days before to consider a growing body of evidence of airborne transmission, Emily Rauhala and Ariana Eunjung Cha reports.

The WHO update notes there have been outbreaks in “closed settings, such as restaurants, nightclubs, places of worship or places of work where people may be shouting, talking, or singing,” 

In a statement, WHO spokeswoman Ashley Baldwin said: “Research on airborne transmission is growing but the evidence is not definitive. Airborne transmission in crowded, closed and poorly ventilated settings cannot be ruled out. However, the evidence needs to be gathered and interpreted.” 

Public health guidelines have largely focused on transmission by close or direct contact, and that remains the focus of the WHO’s guidance. 

OOF: The president continues to sideline top public health agencies as tensions escalate over coronavirus response.

In June, a senior adviser to a top Health and Human Services Department official sent an email to the director of the Centers for Disease Control and Prevention accusing the agency of “undermining the President” by releasing a report about the risks of the coronavirus to pregnant women. It was just one example of the growing pressure on the nation’s public health agency, Lena H. Sun and Josh Dawsey report. 

“In a White House guided by the president’s instincts, rather than by evidence-based policy, the CDC finds itself forced constantly to backtrack or sidelined from pivotal decisions,” they write. “The latest clash between the White House and its top public health advisers erupted Wednesday, when the president slammed the agency’s recommendation that schools planning to reopen should keep students’ desks six feet apart, among other steps to reduce infection risks.” 

One official told The Post that Trump thinks the CDC is “ineffective” and a “waste of time,” though he does generally like CDC Director Robert Redfield. But Redfield is not a voice in coronavirus task force meetings and also not present in the Oval Office with Trump, another senior administration official said. Analysts point to the tension as in part undermining the CDC’s authority during a massive public health crisis. 

“In the absence of strong federal leadership, state and local officials have been left to figure things out for themselves, leading to conflicting messaging and chaotic responses,” Lena and Josh write. “… The CDC, meanwhile, is increasingly isolated — a function both of its growing differences with the White House and of its own significant missteps earlier in the outbreak.” 

OUCH: A small study adds to evidence that pregnant woman can pass the coronavirus on to babies. 

From a preliminary study of 31 pregnant women, researchers found the virus and antibodies against it in the umbilical cord blood, breast milk, placentas and vaginas of some pregnant women who were infected. 

“Just two of the infants in the sample examined by Italian researchers tested positive for the virus, and both quickly recovered,” Lenny Bernstein reports. “In one case, a baby tested negative two days later, an indication that the child was already producing antibodies against the virus in the womb, said Claudio Fenizia, an assistant professor of immunology at the University of Milan, who led the study.” 

Fenizia also said it was too soon, based on the preliminary study, to draw conclusions for how to care for infected pregnant women, and noted there are no proven interventions for pregnant women. He suggested it should raise awareness about transmission. 

Lenny adds: “Fenizia said the results suggest it may be important as the pandemic continues to monitor pregnant mothers and newborns for signs of inflammation, especially in light of the discovery of an alarming inflammatory syndrome linked to covid-19 that has affected hundreds of children in the United States.” 

The ongoing debate about reopening schools

Reopening schools has become the nation's thorniest political and epidemiological issue.

So write Joel Achenbach, Laura Meckler and Chelsea Janes, in this interview with top infectious disease expert Anthony Fauci. 

“It’s not going to be easy because we’ve never done it before,” Fauci, director of the National Institute of Allergy and Infectious Diseases, told our colleagues. “This is uncharted waters — always remembering the primary issue is the safety and welfare of the children as well as the teachers who are going to be interacting with the children.”

“The reopening of schools is likely to be halting and improvisational. It could be marked by setbacks," our colleagues write. “There is no proven strategy for the remobilization of 56.6 million K-12 students amid a pandemic like this one.”

People under age 25 account for fewer than 200 covid-19 deaths. As we noted earlier, only a few dozen kids under age 15 have died from it. But it’s unclear to what extent kids can still transmit it to each other and to vulnerable adults — such as their teachers or family members. 

“Scientific research on children and covid-19 has not been nearly as extensive as research on older people, because there haven’t been nearly as many sick children to study, and children are rarely tested as part of disease surveillance programs,” Joel, Laura and Chelsea write.

“Much of the scientific understanding of how the coronavirus affects children is provisional. A study by researchers in the United Kingdom published last month found that children are only about half as likely as adults to become infected with the virus. Another study, from the University of California at Berkeley, did not see any significant effect on the community spread of coronavirus from the closing of schools in March.”

Schools are facing enormous new financial pressures.

“As the White House, the nation’s pediatricians and many worn-down, economically strapped parents push for school doors to swing open this fall, local education officials say they are being crushed by the costs of getting students and teachers back in classrooms safely,” the New York Times’s Dana Goldstein reports. 

Schools are starting to retrofit buildings, add staff, buy protective gear and make sure students have the academic and emotional support they need. Schools are warning that even those that want to physically reopen may not have the money to do so safely.

“The federal relief package passed in March dedicated $13.5 billion to K-12 education — less than 1 percent of the total stimulus,” Dana adds. “But education groups estimate that schools will need many times that, and with many local and state budgets already depleted by the economic impact of the coronavirus, it is unclear where it will come from.” 

Some epidemiologists are making a case for reopening schools.

In a piece for Vox, epidemiologist and father Benjamin P. Linas writes that many families are “living a nightmare,” considering choices that are “high-stakes and plagued by uncertainty. Even thinking about them makes me sweat.” 

He notes that while there are many unknowns, he says one thing that appears clear is that children “are less likely than adults to be infected with Covid-19. … Finally, even in the worst-case scenario, in which a child does contract Covid-19, the outcomes of the disease are less severe in younger people than among older adults.” 

Linas, an associate professor of epidemiology and an infectious-disease physician at Boston University School of Medicine, also noted that while someone could contract covid-19 from a child who brings the virus home, he doesn’t think he would “structure my life around such a rare occurrence.” 

And while Linas acknowledged another unknown is whether reopening schools will lead to another wave of infections, he writes that there are “real risks to keeping our children at home. In fact, the risks of staying home are in many ways clearer than the risks of returning to school.” 

“Ultimately, when I look at the decision about school as both a father and a scientist, I see a difficult decision that must be made despite uncertainty. The risks of opening are uncertain, but the benefits are clear,” Linas writes. “We need to try to reopen.” 

It's still an election year

Republican officials are preparing for the possibility of holding their party’s convention outside. 

The convention is currently set to be held in Jacksonville, Fla., at the VyStar Veterans Memorial Arena next month. Officials are now studying two outdoor sports stadiums near that arena, Josh Dawsey reports

Republicans involved in the planning process say having the convention outdoors could minimize possible transmission and spread of the coronavirus, and that changing the location could ease any potential concerns for attendees. 

“This marks the latest uncertainty over planning the convention, which President Trump is determined to hold even as cases surge in Florida and other states. Officials have engaged in weeks of intensive planning for the convention, which was moved from North Carolina after a sharp disagreement with state leaders there over health measures,” Josh writes. 

Trump is expected to make a decision soon and was recently briefed on the options for moving 

Congress on coronavirus

White House officials and congressional Republicans are weighing a limit to any next round of stimulus payments. 

As lawmakers have been in talks about the next stimulus package, congressional Republicans and White House officials are considering the next stimulus payments after in March approving $1,200 stimulus payments for as many as 159 million U.S. households. The next payment could be limited to a narrower group than the previous check that was available in full for those who earned less than $75,000 in 2019, Jeff Stein and Erica Werner report. 

“The exact number they will seek is unclear, as talks are fluid. One person cautioned that Republicans may ultimately revive the original proposal because of the difficult administrative challenges created by trying to narrowly target the checks,” they write. “At two events this week, Senate Majority Leader Mitch McConnell (R-Ky.) said the payments should be sent out primarily to help those earning under $40,000, but it was not clear whether he was suggesting that would be the new cap. An aide to McConnell declined to comment.” 

The efforts to narrow the next payments come amid pressure on Republican leadership to limit spending in the next stimulus bill. 

Coronavirus latest

Here are a few more stories to catch up on this morning: 

In the state: 
  • Texas state health officials are providing little information on the impact the pandemic has had on child-care facilities, leaving parents in the dark as they try to decide whether they can trust such facilities, the Texas Tribune’s Aliyya Swaby reports.
  • Mississippi health experts are warning that the five largest medical institutions there have run out of space in intensive care units, Michael Brice-Saddler writes for The Post’s live blog.
  • Five states — Alabama, Iowa, Missouri, Montana and Wisconsin — hit new single-day case highs yesterday, Kim Bellware and Jacqueline Dupree report for the live blog.
  • San Francisco Mayor London Breed has she tested negative for the coronavirus after she learned she was at an event with someone who knew they were infected, Lateshia Beachum writes for the live blog.
The latest on the surge in cases: 
  • The number of deaths across the country have increased this week, according to Post tracking, a potential signal that deaths are catching up with the recent surge in coronavirus cases, Michael writes.

Sugar rush

Nationals third baseman Carter Kieboom talked about how the 2020 baseball season being delayed due to coronavirus allowed him to continue to work on his game. (The Washington Post)