Pence’s In-Person Debate With Harris Stirs Public-Health Worries

(Bloomberg) -- Whether Mike Pence should even attend the vice-presidential debate on Wednesday night in Utah, where he'll square off against Kamala Harris, is shaping up as a public-health debate of its own.

Robert Redfield, the U.S. Centers for Disease Control and Prevention Director, personally cleared the vice president to participate, saying in a memo released late Tuesday that Pence was “not a close contact of any known person with Covid-19, including the president,” and citing repeated negative tests.

But it's likely Pence was exposed to President Donald Trump prior to the president's diagnosis, and thus is at risk of developing the infection, according to public health experts who note that symptoms can appear as much as two weeks after exposure. They say Redfield's determination is at odds with CDC guidelines that recommend staying home for two weeks after being within six feet of someone with Covid-19 for at least 15 minutes.

Pence appeared to have been sitting within six feet of the president at a Sept. 26 Rose Garden event when the president announced his Supreme Court nominee, said Rochelle Walensky, chief of the infectious diseases division at Massachusetts General Hospital and a professor at Harvard Medical School.

Meanwhile, others in Pence's vicinity at the event have also tested positive.

That meets the CDC's guidance to quarantine for 14 days, Walensky said, adding that a negative test isn't enough to leave quarantine.

Safety precautions will be taken at Wednesday's debate. Pence and Harris will now be seated 12 feet apart, a change made after the president's diagnosis, and plexiglass partitions have been installed by each desk.

The use of distancing, barriers and negative PCR tests as close to the debate as possible should be adequate, said Roger Shapiro, associate professor of immunology and infectious diseases at Harvard T.H. Chan School of Public Health, who is also a former CDC epidemiologist

“When you put all of that together I think you can reduce the risks quite a bit and make it safe,” Shapiro said.

The new coronavirus is thought to spread largely through droplets created when people breathe, talk and cough. Individuals within six feet of each other are considered at the most risk. But, according to recently updated CDC guidelines, the virus can also spread at distances of more than six feet, through small particles that linger in the air for as long as hours. Data suggests that's less common.

Plexiglass barriers can block the spread of large droplets when people are in close proximity, like at a grocery store cash register. It's like “a shield to protect you from someone who is trying to spray you with a water gun,” said Shelly Miller, a professor of mechanical engineering at the University of Colorado Boulder.

Hundreds of Aerosols

But Miller and Linsey Marr, an engineering professor at Virginia Tech who is an expert in aerosol science, see another level of threat, even when two debate candidates are already 12 feet apart. Plexiglass doesn't stop the small particles known as aerosols, “which can easily follow air flow around the barriers,” Marr said, comparing the phenomenon to cigarette smoke.

“Hundreds of aerosols come out of our mouths with each breath when we're talking,” Marr said, “and they account for a substantial amount of transmission of COVID-19.” The debate site should instead have both candidate wear masks, or move the event outside, according to Marr.

Walensky, too, remains unconvinced. “There are no guidances for how you behave if you're not going to be quarantined,” she said, “because you're not supposed to do that.”

The University of Utah, which is hosting the debate, has previously said that about 100 students will be in attendance, though spaced out and required to wear masks.

In addition to the risk posed to Harris, many people will also be involved in transporting the vice president to the debate, and “all of those people will be exposed,” she added. “This is why I find this very important, that we follow the CDC guidance.”

Meanwhile, Angela Rasmussen, a Columbia University virologist, said she believes Pence should quarantine until Oct. 13, citing a video from last week in which Pence said he had just been with the president in the Oval Office on Tuesday, prior to the presidential debate that day.

In a tweet on Wednesday, Rasmussen called Pence's decision to attend the debate in person “irresponsible.”

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