JACKSON — Last summer, businesses across Jackson sporadically put up signs: “Closed due to COVID-19 exposure.” Even if staff members weren’t sick, they were quarantined because of their proximity to the coronavirus.

This summer, similar signs are going up because of the workforce housing crisis, but the emergent Delta variant threatens to exacerbate the problem. Part of the recent spike in COVID-19 cases in Teton County were a pair of workplace and congregant living clusters, the type of localized outbreaks that could significantly limit a business’s ability to stay open.

“With the Delta variant, if this goes through an unvaccinated group of people, you’re looking at what we saw last year, which was you didn’t have enough people to turn the lights on,” Teton County Director of Health Jodie Pond said.

Teton County’s vaccination rate — 68.5% of adults, according to Wyoming Department of Health data — provides some insulation against widespread outbreaks of the Delta strain and other variants. COVID-19 vaccines have been shown to protect against the Delta variant and prevent severe disease and hospitalization in a high percentage of cases.

So far, epidemiologists’ biggest concern is the Delta variants’ increased transmissibility, up to 225-percent faster than the original strain of SARS-CoV-2. One preprint study from China, which has not yet gone through the peer-review process, shows people infected with the Delta variant might have 1,000 times more copies of the virus in their respiratory tracts.

Recent clusters in Jackson have not been attributed to the Delta strain, though Pond suspects it might be responsible. She asked the Wyoming Department of Health’s Public Health Laboratory to sequence the positive tests from them to determine if the variant was to blame.

Statewide, Delta is becoming more prevalent, with the majority of cases being found in the past two months. State Health Department data shows that 191 cases of the strain have been found in Wyoming, second only to the Alpha variant.

Though Wyoming’s case counts are lower than many states, the state leads the nation in percentage of cumulative cases sequenced. That allows public health officials to monitor variants, particularly as they drive case growth.

“The lower our vaccination rates, in combination with this variant that is highly contagious, the more at risk we are for seeing increased cases of COVID-19 and illnesses,” state Health Department spokeswoman Kim Deti said.

That’s where Teton County’s higher vaccination rate comes in handy, but there are sub-communities with lower levels of protection. Kids under 12 aren’t eligible for vaccination yet, and just 42.55 percent between the ages of 12 and 17 are vaccinated.

Those unvaccinated kids, along with pockets of seasonal workers and other younger groups, are at higher risk of infection, especially with more transmissible strains like Delta. For anyone who isn’t vaccinated, Deti said, the advice that was in place throughout the bulk of the pandemic still applies.

“For those people who are not eligible for vaccination, including children under the age of 12, common-sense precautions such as wearing masks indoors and avoiding spending time indoors with people outside of the household are recommended,” she said. “Parents can help protect their children by ensuring they themselves are vaccinated.”

Especially for Jackson businesses strapped for employees, Pond said, vaccination represents the clearest way to avoid a Delta surge that could shut down an establishment for a couple of weeks. The symptoms from Delta appear to be more traditional cold signs like a runny nose and headache.

The Health Department now offers a mobile clinic, the vaccine bus, which will set up shop at any business where employees might not have time to leave work to get shots.

For parents who want their eligible children to be protected before school starts, the Pfizer vaccine — the only one approved for kids as young as 12 — takes five weeks to reach full protection. So with the first day of school being at the end of August, there isn’t much wiggle room.

“If you want your kids to be fully vaccinated before school, you should think about coming in pretty quickly,” Pond said.