By the numbers: How Vermonters are catching COVID-19

We know the measures Vermonters have taken to combat the COVID-19 pandemic. They’ve become the Green Mountain State’s pandemic refrain: Masks, distancing, hand-washing.

And, most importantly, it’s worked.

“These seemingly routine actions have an important cumulative effect,” said Dr. Mark Levine, the state’s health commissioner, at a press conference earlier this month. “By taking these actions every single day you reduce the chance you’re exposed to the virus and you help protect others.”

Sacrifices have been made — gatherings limited, events and trips abandoned, business restricted. Vermont’s efforts to curb the spread of the novel coronavirus top those of the rest of the United States in nearly every key metric.

But neither the success nor the statistics that support it answer a very important question: 

How have Vermonters contracted COVID-19 in the first place?

To gain a sense of when and where Vermonters are most at risk of becoming exposed to the virus, the Free Press requested data from the Department of Health’s contact tracing efforts. That information, compiled over the first six months of the pandemic, offers several notable takeaways.

Vermont Health Commissioner Dr. Mark Levine, left speaks at a news conference announcing the first case of coronavirus, or COVID-19, in Vermont. He was joined by Gov. Phil Scott, right, and several other state officials at the announcement in Waterbury on Sunday, March 8, 2020.

Most people know how they were exposed to COVID-19

There are roughly 165 cases for which Vermont Department of Health could not collect information about the source of exposure, the majority of which occurred before June 1. 

But the state does have an idea how most of the rest of the cases have materialized. According to data as of Sept. 8, there are 941 cases — about 63% — with a known source of exposure. 

The state’s contact-tracers have gathered that the main sources of exposure for Vermonters break down as follows (some cases had more than one possible source):

Confirmed cases: About 2/3 of the cases with a known source (622) identified another confirmed case as their exposure point.

More:Burlington-Winooski COVID-19 outbreak formally closed, city, health officials say

Outbreaks: Roughly half of the cases with a known source of exposure (457) are associated with an outbreak, when two or more people contract the virus at the same time and place. The state has identified 27 outbreaks to date — those at long term care facilities accounted for the most cases, while the Burlington-Winooski community outbreak in June involved the most people.

More:Vermont officials following COVID outbreak after private party in Killington

Travel: 130 cases are known to have involved travel outside Vermont in the two weeks before displaying symptoms or testing positive.

Close contacts: As of late August, the state knew 198 cases involved “close contacts” of the source case, according to a weekly summary from the Health Department. Of these, 63.9% were people living in the same household, either immediate family or roommates, 16.7% were extended family, 5.9% were friends and 4.5% were co-workers.

Price of admission: a normal temperature. Barbara Bolger, a registered nurse at University of Vermont Medical Center, takes the temperature of Free Press Reporter Joel Banner Baird before he is allowed to tour UVM's Patrick Gymnasium, which workers are converting into a 50-bed overflow facility for COVID-19 patients on April 7, 2020.

Nearly 20% of cases traveled outside Vermont

There were 294 cases known to have traveled out of state in the 14 days before showing symptoms as of Sept. 8. But not all of these cases have a known source of exposure, as referenced above. About 98% of these cases (260) were Vermont residents.

More:You can’t get there from here: Why New England travel quarantines vary

State epidemiologists have not yet cross-referenced individual cases with the travel destinations to determine where Vermonters were most likely to be exposed to COVID-19, according to the Health Department. 

What about cases from unknown sources? 

These make up about 35% of the state’s total cases, according to Health Department data from Sept. 3.

Unknown cases are categorized as such when no epidemiological link is established — there’s no connection to an outbreak, a confirmed COVID-19 case or a history of travel out-of-state.

People working in essential jobs are more likely to contract the virus without knowing how, according to the Health Department. Officials were unable to pinpoint the exposure source for roughly 2/3 of cases involving people with jobs related to non-restuarant hospitality, grocery, travel or retail.

The notable exceptions to this trend have been health care workers (34%) and restaurant workers (25%).

Cases with an unknown source peaked at 42% in March, when community spread of COVID-19 was more significant, according to state experts. They reached a low of 23% in June. 

Children, teens and those age 80 or older were the least likely to contract the coronavirus from an unknown source, according to a state data summary in July. 

Other things we know

A customer, right, picks up his pizza at the Woodbelly stand at the Capital City Farmers Market in Montpelier on Saturday, May 2, 2020.

A study published Sept. 11 by the Centers for Disease Control and Prevention involving nearly 300 adults who tested positive for COVID-19 showed that they were more than twice as likely to have reported dining at a restaurant than people who tested negative.

Lauren Prinzing, an epidemiologist with the Vermont Department of Health, said Monday that state experts have not begun to comb through the state’s data to confirm if the same trend holds here. 

However, a Washington Post analysis showed that Vermont was one of only a handful of states not to experience an uptick in cases of coronavirus after reopening bars and restaurants earlier this year. New Hampshire, New York and Rhode Island were among the others.

Contact Austin Danforth at 651-4851 or edanforth@freepressmedia.com. Follow him on Twitter at @eadanforth.

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