In the central San Joaquin Valley, blowing dust can carry a deadly fungus, and 2017 was a bad year for breathing the fungal spores.
Last year, California had the highest rate of Valley fever since the state began collecting data on cases in 1995 — and most of the people infected were in the San Joaquin Valley.
California had 7,466 infection cases for a rate of 18.8 per 100,000 population, up substantially from 2016, when the rate in California was 14.0 per 100,000 or 5,509 cases; and in 2015, the rate was 8.1 per 100,000 or 3,154 patients.
California and Arizona have the most Valley fever cases. And in California, the Valley has long held the top spot for infections. In 2017, Kern County had 2,748 cases and was the county with the highest incidence rate of 305.7 cases per 100,000 population.
Kings County had the second-highest rate at 172.7 cases per 100,00 or 260 patients, according to a California Department of Public Health summary of cases for 2017. San Luis Obispo had the third-highest rate at 150.4 with 419 patients; Fresno had a rate of 82.4 with 824 patients; Tulare had a rate of 58.2 with 275 patients, and Madera had a rate of 41.3 with 65 patients. Merced had the lowest rate of any Valley county at 17.0 per 100,000 and it had 47 cases in 2017.
Valley counties, except for Merced, had significant increases from 2015 and 2016. For example, Kings County had 104 patients in 2015 and 235 patients in 2016. Fresno County had 274 patients in 2015 and 611 in 2016. Tulare County had 115 patients in 2015 and 240 in 2016.
But it’s likely “two to three times” more people in the Valley had Valley fever than were counted by the state, said Dr. Michael Peterson, a pulmonologist and associate dean of UCSF Fresno. “We see this on a daily basis,” he said.
Why the uptick?
It’s difficult to predict bad years for Valley fever, Peterson said. And it’s unclear why 2017 became a bumper year for the spores in the Valley, but dry weather and blowing dust may be contributing to the increase, Tulare County health officials said.
Valley fever or coccidiomycosis, is caused by breathing in fungal spores found in soil that become airborne and carried in dust. The spores can reproduce in the lungs; in many cases, the infection causes flu-like symptoms that resolve on their own. In other cases, the infection can mimic pneumonia and doctors may not suspect Valley fever, and not test for it, Peterson said. The state report reflects people who were given a diagnosis of Valley fever.
The infection can spread beyond the lungs and anti-fungal medications are prescribed to help treat the infection. But Valley fever can be fatal.
Dr. Milton Teske, health officer for Kings County, said the worst Valley fever case he has seen involved an immigrant from Ethiopia who became infected. The infection spread into his bloodstream. “It was in his skin and bones,” Teske said. The man died, he said.
Symptoms of Valley fever include fever, chest pain, coughing, fatigue, chills, night sweats, joint aches and a red spotty rash, mostly on the lower legs. In some cases, it can lead to chronic pneumonia and leave nodules in the lungs. There is no vaccine for Valley fever, and although researchers are working on a vaccine, Peterson said it’s unlikely there will be a shot any time soon.
Anyone with symptoms should see their doctor or visit a health clinic. Doctors may order a blood test, a chest X-ray or other tests to diagnose the infection. The most vulnerable to Valley fever are older adults, pregnant women and people with weakened immune systems. African American, Native American, Filipino and Hispanics are at greater risk of getting Valley fever.
Barbara Anderson: 559-441-6310, @beehealthwriter