Valley fever is a fungal disease that occurs only in certain parts of the United States and South America. A person can only contract it by inhaling fungal spores.
It can lead to fever, chest pain, coughing, and some other symptoms.
Valley fever is caused by the fungus Coccidioides immitis (C. immitis), or by Coccidioides posadasii (C. posadasii). It is also known as coccidioidomycosis, California disease, desert rheumatism, and San Joaquin valley fever.
The fever does not pass between humans. An infected person will not transmit the disease to another person.
In the states where the fungus is active, there are 42.6 cases per 100,000 people every year, on average.
There are three different types of valley fever.
Acute valley fever
Valley Fever is most common in Arizona.
Initial symptoms are mild. Some people will have no symptoms at all, and they only know about the infection when they test positive during a skin or blood test.
The University of Arizona estimates that over 60 percent of infected people have either no symptoms or experience flu-like symptoms and never seek medical attention.
Signs and symptoms can appear approximately 1 to 3 weeks after exposure.
They may include:
chest pain – may be mild or quite severe
shortness of breath
A skin rash can occur. This generally consists of spotty red bumps on the lower legs, which may be painful. Eventually, they become brown, known as erythema nodosum.
The rash may also appear on the back, arms, or chest. More rarely, it may produce blisters.
Individuals who are otherwise healthy will normally recover completely within 6 months.
In patients with severe symptoms, complete recovery may take up to a year. Fatigue and joint pains may persist for longer.
Chronic valley fever
Rarely, a patient with acute valley fever does not make a full recovery, and the condition progresses to a chronic form of pneumonia.
This is more likely in those with a weakened immune system.
Signs and symptoms include:
blood-stained spit (sputum)
Symptom severity may fluctuate between individuals and over time.
Disseminated valley fever
This is the most serious form of valley fever. It happens when the infection spreads from the lungs to other parts of the body through the bloodstream.
It can affect many organs, and particularly the skin, liver, brain, bones, meninges, and heart.
Signs and symptoms vary depending on which parts of the body are affected.
They may include:
skull lesions, which are often painful
lesions in the spine and other bones
swollen joints, which are usually painful
meningitis, or inflammation of the membranes around the brain and the spinal cord
muscle aches and stiffness
neck or shoulder stiffness
change in mental status
photophobia, or sensitivity to light
Without treatment, it can be fatal.
Valley fever is caused by a fungus found primarily in certain parts of the United States and northwestern Mexico.
A number of common factors increase the likelihood of contracting valley fever.
Geographical location: the risk is higher in areas where fungus spores are likely, such as Arizona, New Mexico, Texas, Utah, Nevada, and northwestern Mexico. If the person inhales the spores, they can become infected.