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Victor Gutierrez doesn’t know when he contracted valley fever, an illness caused by a soil-borne fungus, but he’s narrowed it down to a few possible jobs he worked during the summer of 2011.

In the nectarine orchards, Gutierrez recalls, “the wind was really strong, and we were almost falling off our ladders. The dust would rise up in the fields and we would get lost in in [it].” The grape harvest that year wasn’t much better. “We would walk out of the vineyard with our faces full of dirt. Only our eyes were visible,” he said. When he showered at night, he could see the layer of soil washing off his body.

Late that summer, Gutierrez started experiencing flu-like symptoms—a cough, night sweats, exhaustion, and a strange feeling that he was burning up on the inside. Gutierrez ignored it and kept working for fear of losing his job. But when he struggled to breathe, he went to see a doctor, who gave him a dose of antibiotics and told him to buy a humidifier.

The next day his lungs filled up with fluid and he felt so bad that he went to a local clinic. This time, they tested him for valley fever, and it came back positive.

“The nurse called me and told me to rush to the clinic because it was an emergency,” he said. Gutierrez, who was 33 at the time and a father of three, had never heard of valley fever. He was told he might only have six months to live.

While Gutierrez managed to beat those odds by taking the antifungal medication fluconazole for more than a year, he has seen valley fever kill many other people he’s known. Of the five people he recalls seeing diagnosed with the fungal infection on that day in 2011, he said he’s the only survivor.

Still, valley fever remains dormant in his body—and it could come back at any point. Gutierrez still struggles with regular pain in his lungs and when he gets a cold or flu, he’s in bed for weeks.

Coccidioidomycosis or cocci (pronounced “coxy”) thrives in dry, undisturbed soil; it becomes airborne when that soil is disturbed—whether it’s by dirt bikes, construction crews, or farmers putting in new fruit or nut orchards. It can travel on the wind as far as 75 miles away. Years of climate change-fueled drought and a 240 percent increase in dust storms appear have led to a swift rise in the number of people diagnosed with the illness across the Southwest.

According to the California Department of Public health, new cases in the state rose 10 percent between 2017 and 2018. California budgeted $8 million for valley fever research in 2018, and about $3 million will go toward expansion of the Valley Fever Institute at Kern Medical hospital. Three new laws also address Valley fever reporting, testing, and education in the state. In 2011, California spent approximately $2.2 billion in valley fever-related hospital expenses.

(Photo CC-licensed by Peter Haden.)

The Tip of the Iceberg

Getting an accurate count of the number of people affected by valley fever is a challenge because the majority of those who are infected never know they have it. However, new cases are especially concentrated in the San Joaquin Valley, home to the farms that produce two-thirds of the nation’s fruit and nuts and one third of its vegetables; the two cities with the worst particle pollution in the U.S.; and most of the state’s farmworkers.

In 2017, the Centers for Disease Control said the 14,364 cases of valley fever were reported nationally, but that “tens of thousands more illnesses likely occur and may be misdiagnosed because many patients are not tested for valley fever.” On average, there were approximately 200 deaths associated with the illness each year in the U.S. between 1999 and 2016.

Dr. Royce Johnson, director of the Valley Fever Institute and professor of medicine at the University of California, Los Angeles said 60 percent of valley fever cases are misinterpreted as the flu and go undiagnosed. Johnson, who has been working with valley fever patients for more than 40 years, said the remaining 40 percent tend to experience symptoms that are similar to, and often confused with a serious case of pneumonia. From there, a small percentage—around 1 percent of the total people infected—sees the disease spread to other parts of the body, including the brain and the skin.

“People with relatively uncomplicated [respiratory valley fever] will usually think this is the worst illness they’ve ever had,” Johnson said, adding that the symptoms can get quite a lot worse in cases where it spreads. Patients are treated for between three and 12 months and then tracked for an additional two years to make sure the disease doesn’t come back or spread.

“A lot of people don’t understand how manifold and complicated valley fever can be,” said Johnson.

Valley fever is not passed from person to person, but epidemiologists are still trying to determine what exactly puts people at risk, aside from simply being outside, said Stephen McCurdy Professor of Medicine in the Department of Epidemiology and Preventive Medicine at the University of California, Davis, which created the California Center for Valley Fever in 2016.

Immune function is one key factor, putting at elevated risk pregnant women, some diabetics, people with HIV, the elderly, and those who are on immunosuppressant drugs or have had organ transplants. Race appears to be another important factor, McCurdy said. “It seems that darker-skinned people are more likely, if they contract valley fever, to get a more severe case of it. In the majority of cases, people knock it back themselves [like a typical flu]. People with darker skin seem to be less able to do that.”

It’s not entirely clear just why that is. “I’m sure it’s related to whatever genetic resources those groups have compared to others.”

According to a study by the California Health and Human Services Agency, African Americans and Hispanics in California are more likely to be hospitalized with valley fever than whites.

“A contributing factor to this finding may be the large populations of Hispanics living and working in the endemic region counties of California,” wrote the study’s authors, who added that the connection between race and risk for the disease “is not well understood and may be attributable to variations in genetic susceptibility.”

A 2011 study done in Arizona found that Latinos and African Americans are also more likely to die without being diagnosed, and another study done in Kern county in the 1990s also found the rate of valley fever incidence was elevated among Latinos.

An orange orchard in Lindsay, California. Photo by Twilight Greenaway.

Another challenge with gathering data, said Carol Sipan, a public health lecturer at University of California, Merced, is the fact that “many [farmworkers] would go back to Mexico if they got really sick.” In Mexico, she adds, valley fever is not a reportable disease.

Farmworkers in the Crosshairs

Like many farmworkers who contract the illness, Victor Gutierrez found the cost of the antifungal medication needed to treat valley fever astounding. At the height of the illness it cost $1,200 for two months of pills because he had to take two to three times as many as one would if they were treating a typical candida infection.

He didn’t have insurance at the time and said his family often had to choose between food and his medication. He still isn’t able to work regularly and the family of three mainly relies on the money his wife, Maria, makes in the fields to survive.

“It has changed my life a lot,” said Gutierrez. When I used to work, I would always have money in the house—to eat, to buy my children clothes, for everything. But right now, I have debts,” he said.

Like 68 percent of the estimated 800,000 farmworkers in California, Gutierrez was born in Mexico. An estimated 49 percent of the states farmworkers lack work authorization and most live under the federal poverty line in unincorporated communities with few public services.

Meanwhile, the Central Valley’s long harvest season brings long hours, extreme heat, and other challenging conditions. At home, these workers face limited access to health and education, an array of mental health challenges, and high rates of food insecurity. Valley fever only adds to these challenges.

Isabel Arrollo-Toland knows both sides of this story intimately. She is the daughter of a former farmworker who directs a small nonprofit organization, El Quinto Sol de America, which trains farmworkers and other recent immigrants in civic engagement in a handful of unincorporated communities in Tulare County, an hour south of Fresno.

Arrollo-Toland was diagnosed with valley fever in 2007 and again in 2008 when it spread to her skin—and both times she endured months of misdiagnosis. Then, in 2012, she was told that her kidneys were failing due to the impact of both valley fever and the medication she had relied upon to treat it. Since then, she’s had to do peritoneal dialysis for 10 hours every night. She’s currently on the donor list for a kidney.

Arrollo-Toland makes it a point to advise the workers she knows to get tested for the illness at the first sign of a cold or flu. “Sometimes I’ll be talking to a farmworker and they’ll say “Oh, I have these symptoms …” And my first thing is, “You should go get tested for valley fever.”

Isabel Arrollo-Toland is the executive director of El Quinto Sol de America, an organization that trains farmworker in unincorporated communities in civic engagement. She has had valley fever twice. Photo by Twilight Greenaway.

She also points to the many challenges farmworkers face when it comes to staying healthy—from regular exposure to pesticides and dust clouds, to lack of fresh produce and clean water—a growing challenge for many residents of unincorporated areas.

“It’s really difficult to say you have to keep your immune system at 100 percent, because your environment doesn’t provide that for you,” said Arrollo-Toland. “Seeing the doctor for prevention is another issue because you have to go to the clinic, which is probably 30 minutes away… and always so full.”

Several studies have shown that farmworkers suffer from elevated levels of chronic stress and anxiety—two more factors that have been linked to suppressed immune function.

In U.C. Davis professor McCurdy’s recent research, he found that “[The people who reported having valley fever] lost about 20 work days of on average while they were sick.” McCurdy is currently working with other researchers on two studies involving farmworkers and valley fever, including one that involved surveying nearly 120 Latinx workers at two migrant labor centers in Kern County.

The Role of Agriculture

While pesticides don’t play a direct role in the spread of valley fever, Antje Lauer, a microbial ecologist at the California State University, Bakersfield who has received funding from NASA, the U.S. Department of Defense, and the Bureau of Land Management to study valley fever in the soil, does see that certain forms of agriculture as a potential part of the problem.

Lauer draws a connection between the perpetual haze surrounding the major cities in the Central Valley cities and the way the region is farmed. “The pollution is actually homemade,” said Lauer. “Most of the agriculture that we have here in the valley contributes to our poor air quality… Once the agricultural season starts with plowing and planting new orchards, we have an increase in fine particulate matter.”

Research has shown that the cocci fungus doesn’t tend to thrive in irrigated farmland—mainly because the moisture allows other kinds of soil fungi to thrive. However, Lauer said the jury is still out in the case of orchards that are planted on soil that has been sitting fallow.

On a recent weekday, Lauer drove out to east Bakersfield, where new pistachio and almond trees stretched out for miles—their spindly new trunks poking out of otherwise bare, dry soil. She collected an initial sampling of soil to test for cocci; if she finds it, she’ll come back for more samples.

“You can see how pesticides have removed all the underlying vegetation. So, it’s bare soil and you can see that this is a dust hazard. These are new orchards that I think should not have been allowed to be planted there.”

Antje Lauer in a pistachio field. Image by Nirma Hasty for NBC News.

The stakes are changing, in part because rainfall in the Southwest has become less common and less predictable. Very wet winters, like the one that just passed, followed by dry summers have historically been particularly bad when it comes to the growth of cocci spores, said Lauer.

“The valley fever fungus might actually expand its territory with climate change,” said Lauer, pointing to the fact that cocci spores were found in Washington state in 2014.

Although farmworkers and others who work outside are in an especially risky position, the scientist added that it only takes one exposure to make someone sick. Those who live outside the Southwest are less likely to have developed immunity to the fungus. “You [may] want to visit San Diego Zoo or Disneyland and then you might contract valley fever. When you go back home to Maryland or Iowa or Florida or wherever, your physician might not really have heard much about [valley fever] and might not diagnose you correctly and then the diagnosis might be delayed,” said Lauer

Is Prevention Possible?

While dust masks can be effective at limiting some exposure, it’s not a real solution for those who work in the fields.

Manuela Ortega, a farmworker who contracted valley fever in 2006—and whose brother died of the illness at age 39—said that the stifling summer heat makes wearing a mask unrealistic. “Even though there’s a lot of wind and dirt, people still work. In some cases, it’s good to wear masks, but in other cases, people just need to be sent home,” she told Civil Eats.

None of the farmworkers we spoke to had been given masks or informational pamphlets on the job.

The California Farm Bureau Federation tracks health and safety issues affecting farmworkers, according to spokesman Dave Kranz. “We support research that helps farmers and their employees avoid illness and injury, and work with health experts and farm advisors to make sure farmers and employees have the information they need to stay well and safe,” he added. “That applies to valley fever and to any other illness that could affect farmers and farm employees.”

Two cocci vaccines are in the works—at the University of Texas and the University of Arizona—but it’s not clear how close they are to being tested on humans. Three members of Congress from the Southwest last month introduced a federal bill—the FORWARD Act—in an effort to increase public awareness of the disease while “promoting the development of novel treatments and a vaccine.”

In the meantime, farmworkers and their allies continue to face immense challenges.

Mario Celaya, a physicians’ assistant who was trained as a doctor in Mexico, has been seeing patients at the Vida Sana clinic in Lindsay, California for 23 years. He has seen the rates of valley fever increase in recent years and now treats 3-4 people with the illness every week. The bulk of his patients are farmworkers and their families.

Celaya said a timely diagnosis can make a difference in whether or not a patient is severely impacted by the illness. Because the blood test requires a two-week window before the results are accurate, however, he said false negatives are common. “Patients need to be aware of that if they do not get better in two or three weeks, come back and be rechecked because it could be very bad,” he added.

“If you have to tell them, ‘You cannot work for two to three months,’ it has an impact on their families because, sometimes they are the main source of income. If these patients have to stop working, then the whole family is going to go through difficulties.”

After a decade of living with the illness, for instance, Isabel Arrollo-Toland has gone from being a spontaneous, outgoing young woman to a person who has to live cautiously and maintain a schedule that allows for dialysis every night. She still works hard, fights for clean water and other public services in farmworker communities, but now she has to pace herself. “I’d go out all night if I wanted to, visit [people in other cities], work as long as I wanted to, and now I can’t do that,” she said. “Now, I have to plan.”

Top Illustration by Anuj Shrestha for NBC News.