WENATCHEE – Dozens of farm workers at a Central Washington orchard have tested positive for COVID-19, though they weren’t experiencing symptoms.

Stemilt Ag Services, which operates the orchard, and local health officials tested the farm workers in East Wenatchee after some fruit packaging warehouse workers tested positive. The company said it decided to expand testing to orchard workers as a precaution.

Of the 71 agricultural workers who were tested, 36 were positive for COVID-19, Stemilt reported this week.

Despite social distancing measures in place at the orchards, there were a high number of positive cases, said Barry Kling, administrator at Chelan-Douglas Health District. Some people who have COVID-19 show no symptoms.

“We’ve been relying on symptom checks for deciding who needs to be tested, and who needs to be isolated,” Kling said. “And maybe we need to think differently about the whole thing.”

Stemilt was one of the first companies in the region to test a group of workers that was asymptomatic, but the company is still evaluating its next steps, said Roger Pepperl, Stemilt marketing director, in an email. Stemilt has been following Centers for Disease Controls and Prevention recommendations for social distancing.

Workers who tested negative will be retested and are in isolation, according to a Stemilt press release. All workers who were tested are work visa holders and arrived around February.

United Farm Workers and other advocates filed a lawsuit about a week ago against Washington state, arguing that farm workers do not have adequate protections. The groups called on the state departments of Health and of Labor & Industries to update safety guidelines.

United Farm Workers is a union but does not represent the Stemilt workers who were tested.

The state issued a draft of new guidelines for temporary agricultural worker housing, which include increased sanitation practices, social distancing, isolation of workers who tested positive and approval for the use of tents to house temporary workers. The rules are expected to be adopted on May 1 by the Department of Labor & Industries.

But advocates say these guidelines fall short and don’t address transportation for temporary workers.

Farm worker advocates have been working with state agencies and the governor’s office since March 19 to pin down adequate rules to protect workers who live in the U.S. and those who are on work visas, said Rosalinda Guillen, executive director for Community to Community Development, a nonprofit based in Bellingham.

Putting farm workers in tents creates a risk for infections and the virus to spread, and it’s already happening in other places, she said. She added there’s no evidence of increased state funding or staffing to ensure guidelines are enforced.

Cases are “exploding in the agricultural industry and that’s because the protections that were supposed to be implemented have not been implemented and enforced since the very beginning,” Guillen said.

Some members of the agriculture industry in Washington have threatened to sue the governor, Labor & Industries and farmworker unions that have been advocating for additional rules because of the potential economic harm to the industry, said Erik Nicholson, national vice president for the United Farm Workers.

“To argue that money is more important than human health is appalling, and at the end of the day if we don’t protect farm workers, we’re not gonna have food. It’s that simple,” he said.

Additional testing was done at two other facilities in Chelan and Douglas counties, but the district is waiting for lab results to develop additional measures that will protect agricultural workers, Kling said.

There have been 157 confirmed COVID-19 in the two counties, Kling said.

Stemilt has been doing a good job observing social distancing measures, Kling said. But he said the industry might need to alter its approach to farm-worker housing safety guidelines and employee screening.

More widespread testing is under consideration and the capacity for it is expanding, but so far testing has been only been conducted intermittently, he said. And labs still are having trouble getting supplies, he added.

“We’re really concerned about whether it’s really possible to do what the science suggests we really need to do,” Kling said.