Following a press conference held last month on the topic of valley fever, Russell Judd, the CEO of Kern Medical, said something about the disease that struck a chord for many who live in the southern valley.
"If you have a fever and you have a cough and you live in Bakersfield," he said, "you should get a valley fever test."
Simple, right? It seemed like a common sense formula, but it raised questions about whether health care providers really operate that way. And about how valuable the tests are in detecting valley fever in a patient.
Should doctors in Bakersfield order a valley fever test based on these symptoms, combined with the fact that the patient lives in a geographical area that sees more valley fever cases than any other county in California?
Kim Hernandez, epidemiology manager at the Kern County Public Health Services Department, said every health care provider will use their clinical judgement in making decisions about when to test patients for valley fever.
"Fever and a cough is very generic," she said. "What providers test for likely depends on the severity or duration of illness."
When other symptoms are present, the accumulating evidence may help healthcare providers differentiate between illnesses, or decide what to rule out.
For example, the rash associated with valley fever tends to be distinct and may make a provider more suspicious of valley fever. However, not every valley fever patient develops the rash.
Dr. Royce H. Johnson, medical director of the Valley Fever Institute at Kern Medical, and a local expert on the disease, said when deciding when to test, there's more to it than the symptoms and locale.
"No, I would not get tested for valley fever if I had a cold, and I've had several of those since I've lived in Bakersfield," he said. "On the other hand ... if you have pneumonia or a cough that's persistent for more than two weeks, then yes, you should see a physician and be tested — and preferably your primary care physician and not an urgent care and not at an emergency department."
Unfortunately, getting tested early, even when you are infected, may not provide valid information.
"If you have valley fever," Johnson said, "the odds of that testing positive on the first visit is only 50 percent — even when it's done at the health department."
Other tests done at some of the hospitals have numerous false positives and false negatives.
"So you can be over-diagnosed and under-diagnosed by those tests," he said. The tests done at the health department "are the best, but early in the disease, they're not that sensitive."
As a result, repeated testing may be required.
Valley fever is caused by the Coccidioides fungus, which grows in the loamy soil of the southwestern United States. When disturbed, often through agricultural tilling, construction and high wind, microscopic fungal spores can become airborne and, once inhaled, cause valley fever. Most people are asymptomatic, but others develop flu-like symptoms, including fever, cough, headaches and chills. In some cases, when left untreated, the fungal spore can spread throughout the body and cause a lifetime of health issues, and in rare cases, death.
Last year, the respiratory disease killed six people and infected nearly 3,000 in Kern County. It was the highest number of diagnosed cases since 1992, and it was the fourth year in a row Kern saw an increase in diagnosed cases.
Kern County residents regularly account for as many as half of all cases in California. Kern's incidence rate is higher than any other county.
It's impossible to know exactly how many patients in Kern County are tested.
In 2018, the Kern Public Health Lab performed 27,454 blood tests for valley fever, Hernandez said. That number goes up and down every year, but doesn't necessarily reflect the number of cases in the community.
Valley fever testing can be performed at some commercial labs, not just the Public Health Lab.
"All positive results are reported to the Health Department," Hernandez said. "But we do not receive any information about negative results."
The county Health Department also receives specimens from outside Kern County, so not all of the tests that are run at the Kern Public Health Lab are for Kern residents, making the statistics even less clear.
The fee for the valley fever skin test at Public Health is currently $76. The cost for the blood test is $65.
But if you want a valley fever blood test, you can't simply walk into the Public Health lab and be tested. It has to be ordered by a health care provider. However, anyone who wants a valley fever skin test may make an appointment to receive it, but it may not be covered by insurance.