Although most major events closed last summer due to the coronavirus pandemic, the Sturgis Motorcycle Rally rushed ahead and panicked health professionals when nearly half a million motorcycle enthusiasts came to the Black Hills of South Dakota.

This year’s rally, which began on Friday, is expected to attract an even larger audience, as the infectious Delta variant is producing more new virus cases nationwide than at that time last year.

Which route the virus will take through Sturgis remains to be seen.

It is more difficult to transmit outdoors, vaccines greatly reduce the risk of serious illness, and South Dakota has the fewest new virus cases per capita in the United States. At the same time, the Centers for Disease Control and Prevention are viewing Delta as contagious as chickenpox, and people are traveling from across the country – several southern states are in their worst outbreaks of the pandemic – to a region with a relatively low vaccination rate.

Hundreds of new cases have been linked to last year’s rally, but as infected bikers returned to their home states, it made contact tracing difficult and obscured the real bottom line.

Sturgis officials stressed that this year’s rally will offer coronavirus testing, free masks and hand sanitizing stations. For the first time, attendees are allowed to take alcoholic beverages outside without fear of being fined to limit the crowd in the bars.

These precautions are accompanied by warnings.

“We encourage people in a high-risk category, whether because of their age or comorbidities, to come next year,” said Dan Ainslie, Sturgis City Manager.

On Friday, the steady roar of the engines announced the arrival of thousands of bikers. In the morning, Main Street was crowded with visitors, walking shoulder to shoulder on sidewalks, or congregating near dozens of bikes parked outside of stores. A parade opened the 10-day rally, which was in its 81st year, with the Budweiser Clydesdale horses in the lead.

A local business owner, Toni Fisher, 63, had watched anxiously as more and more people poured into her hometown over the past week. Although she and her husband are both vaccinated, Ms. Fisher suffers from fibromyalgia and said she was concerned about the likelihood of developing a breakthrough infection that could affect her health for months.

All the minimal precautions people took last year like so much motorcycle exhaust drifted away, she said. “It’s wild boar this year,” she said. “Nobody cares.”

The pandemic devastated the massage business that Ms. Fisher runs, but she said she was unsure whether she would offer massages during the rally. She has a handful of masked appointments, and she and her husband are once again hosting campers in their garden. Her husband plans to deliver pizzas for extra cash during the rally – adding to Ms. Fisher’s worries.

Updated

Aug 7, 2021, 5:39 p.m. ET

She’s wearing face masks again when she goes to the grocery store, but says she’s practically alone taking precautions, even as the Delta variant is fueling rising infections across the country.

“I don’t know what to do here,” she said.

Other major outdoor events have returned this summer, in part because of vaccine availability. Attendees at the recent Lollapalooza music festival that pushed people to downtown Chicago were required to either show proof of vaccination or show a negative coronavirus test from the previous 72 hours.

There will be no similar screening process at the motorcycle rally in Sturgis. Vaccines will be made available at the event, including the single-dose Johnson & Johnson shot, but they take time to boost the immune system.

Meade County, which includes Sturgis, has a vaccination rate of 37 percent – significantly lower than half of fully vaccinated Americans – and the six neighboring counties have even lower vaccination rates.

Dr. Shankar Kurra, the vice president of medical affairs at Monument Health, headquartered in Rapid City, SD, said the area had almost no virus cases in late June. But like in every other state, cases have risen in the past few weeks.

Understand the state of vaccine mandates in the United States

“With us all 100 percent of the cases were unvaccinated people,” said Dr. Kurra on the recent surge. “We want to make sure people have access to tests so that we can be detected early in the event of an outbreak.”

About a week before the rally began, bikers from across the country started packing up at hotels in Rapid City, said Steven Allender, the city’s mayor. Mr Allender said he has contacted local health officials about how best to prepare for the flow of visitors, but his office has failed to impose any restrictions on the event.

“The government tried to save lives, but failed because of the political climate and the debate over the use of masks,” Allender said. “I would say today that there is no stopping churches across the state from adopting an all-for-yourself stance.”

At the end of last year, Mr Allender issued a mask mandate in all city buildings and called on the city council to issue a more comprehensive regulation on the mask requirement – a measure that ultimately failed. South Dakota was one of several states that did not impose lockdowns or mask requirements during the height of the pandemic.

Sturgis is a relatively quiet town of around 7,000 residents for most of the year, next to 1.2 million hectares of forest and with a motorcycle museum as its main attraction. But every summer the city changes when bikers dismount. Last year, when the pandemic turned daily life in America upside down, forcing music festivals and other large gatherings to be canceled, more than 60 percent of Sturgis residents were in favor of postponing the motorcycle rally, according to a poll sponsored by the city. But this year there was little public concern.

The state’s Department of Tourism estimates that the annual festival, with notable sponsors such as Budweiser, Harley-Davidson and Coca-Cola, will generate sales of around $ 800 million this year. It’s a sight to behold: when drivers from the USA and Canada make the pilgrimage to Sturgis, at least in more typical years, the otherwise quiet stretch of Interstate 90 is overcrowded with motorbikes.

“The Sturgis rally is about jumping on your bike and exploring this great country on our open roads,” said state governor Kristi Noem in a statement. “Bikers come here because they want to be here. And we love to see them! Everything we do in life is at risk. Bikers get that better than anyone else. “

Jack Healy contributed to the coverage.