What the Valley Fever is

The medical condition called valley fever is also known by many other names in the general public, such as desert fever, San Joaquin fever, Posadas-disease, San Joaquin valley fever. The condition is in fact a disease that is caused by the fungi generally residing in the soil in certain parts of the world. This species of the fungi is known as Coccidioides because of which the disease is actually referred to as coccidioidomycosis (CM, in short) by the research microbiologists and physicians. The fungi lodged in the soil gets stirred up to become air-borne when the soil is disturbed during farming operations, digging work for construction or by wind during a storm etc. The fungi in the air can then find its way into the lungs and cause the health problem known as valley fever. The fungus does not cause any severe symptoms in a large number of normal people with normal immune defenses and as such upto 75% of people even when infected by this fungus never feel the need for any medical care as a mild form of the valley fever is cured by the body's immune system on its own. Even when symptoms of the fungal infection are slightly more pronounced, they usually resemble other common lung problems like shortness of breath, cough, sputum production, chest pain and fever. The disease may progress from acute to chronic and progressive lung disease and need prolonged medical treatment in certain cases.
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The disease may also infect some animals like dogs, monkeys, otters and cattle etc.

Causative Factors and high-risk groups

The fungi which are believed to cause the valley fever — the Coccidioides immitis or the Coccidioides posadasii — actually inhabit the alkaline soils of the deserts of some areas like southern Arizona, San Joaquin Valley in California, Nevada and northern Mexico. The disease caused by the fungus is also known to be endemic in some parts of New Mexico, Central & South America and south western United States which generally have arid summers and mild winters. Like various other members of the fungi family, the Coccidioides have the complex life cycle. These grow in the soil as molds with filaments which break off to become airborne spores as the soil gets disturbed under various natural and man-made conditions. These spores being small and extremely light can travel upto hundreds of miles carried by the windy airs and are thus highly contagious. Once lodged in the lungs, the spores start reproducing leading to the symptoms of the disease known as valley fever.

Certain groups of population which face high risk for this fungal problem are African-Americans, Asians and women in late pregnancy as well as smokers, the elderly people and those with diabetes or persons having severely impaired immune systems. The disease in its severe form also particularly strikes the HIV-infected people. The mortality is also higher in the HIV-infected persons who suffer from diffuse lung disease. The infection can also lead to what is called CM-meningitis which may cause even permanent brain damage in some patients.

General Symptoms of Valley fever disease

The Valley fever is actually an acute stage of the coccidioidomycosis (CM) infection. This illness can, however, develop into a serious medical condition like the chronic or disseminated coccidioidomycosis. Listed below are the symptoms of the disease at the three stages:

 a. Acute stage of valley fever

The initial stage or acute form of CM-infection is often quite mild, with few symptoms. Real signs/symptoms generally appear 1-3 weeks after the exposure. These usually resemble the symptoms of a flu which also can range from mild to severe forms of:

i.      Cough & sputum

ii.     Chills & headache

iii.    Shortness of breath

iv.   Chest constriction to intense pain mimicking a heart attack

v.    High fever

vi.   Night sweats

vii.  Joint aches &  feeling of fatigue

viii. Skin rash with red spots – the rash that accompanies valley fever sometimes develops into painful red bumps which may later become brown. These appear normally on the lower legs and sometimes on chest, arms & back too. In some people there is a rash with eruptions looking like pimples.

If someone does develop severe symptoms of CM-infection, the course the disease may follow is then highly variable and it may take from 6-12 months to recover and the joint aches & fatigue can persist for even longer. The severity of the condition depends upon several factors such as the overall health of the person concerned and the amount of fungal spores inhaled by him/her.

b. Chronic stage of valley fever (CM)

If the initial CM-infection is not resolved, it can progress into the chronic stage of pneumonia. This incidence is more common in diabetic persons or in those with a weakened immunity. In this stage one is also likely to undergo bouts of worsening symptoms followed by periods of recovery with signs resembling those of the tuberculosis as under:

1. Formation of lung-nodules & chest pain
2. Throwing out sputum mixed with blood
3. Recurring cough and persisting low-grade fever
4. Loss of weight

c. Disseminated coccidioidomycosis (CM) stage

This most serious stage of the disease is marked by the infection spreading (disseminating) beyond lungs to other body-parts such as the skin, liver, bones, heart, brain and meninges (membranes surrounding the brain & the spinal cord).The signs & symptoms of disseminated CM depend upon the part of the body that gets affected and generally include:

1. Occurrence of ulcers, nodules & skin lesions on the skin
2. Formation of  lesions in skull, spine and other bone-structures
3. Inflamed/swollen joints – usually the knees and ankles
4. CM – meningitis which results from the fungal infection of the meninges and is one of the most serious & deadly complications of the valley fever infection.

Valley fever when it is at the initial symptomatic stage, often goes away on its own. Still in elderly persons and those at higher risks, the recovery is usually slow with risk of developing more severe symptoms disease being higher. Therefore in such cases suitable medical care must be sought at the earliest possible stage.