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The sunny Southwest was a great place for training the fliers of World War II. But it turned out to have a special medical problem. The young airmen and crews at the large flying fields built in the Southwest by the Army Air corps came down with a feverish illness at an alarming rate.

The disease that the fliers had contracted was what local people called valley fever, desert fever, or San Joaquin Valley fever. The technical name is coccidiodomycosis (KOK-sid-dee-OY-do-my-KO-sis) or “cocci,” for short.

Cocci is a sickness of degree. Most people catching it do not get sick at all; they don’t even know they have the disease. Of those who do get sick, most have flu-like symptoms – this is what happened to the airmen. Only a very small percentage of cocci patients develops the disease in its serious, or disseminated, form (widespread throughout the body).



Cocci is a fungus disease – caused by a tiny form of plant life somewhat like yeast or mildew. The tiny seeds, called spores, are found in dust and are inhaled into the lungs. But they can spread to other parts of the body too. In rare cases infection may result when the fungus-filled dust settles in a skin scratch.

The problem of the swirling desert dusts was partially solved by the Air Corps when it learned to control dust stirred up along runways—through irrigation and planting grass or laying more concrete. Infected soil is the danger. The disease is not spread from human to human. After one bout with cocci, the body develops immunity to a second infection. Small desert animals such as gophers and some domestic animals may be infected by inhaling the spores. But they do not spread the infection to human beings.



The disease may occur in any resident of the infected areas – or a visitor; often offering a diagnostic puzzle to the doctor back home. People most likely to be exposed are those in dusty occupations, such as farm workers, earth movers and archaeologists. However, the more serious or disseminated form of cocci is many times more frequent in non-white people, and those with impaired immune systems.

Persons between the ages of 25 and 55 are most likely to develop symptoms of the disease—although people of all ages can have symptoms.

In its simple form, with the flu-like symptoms, cocci affects both men and women equally. But the serious form of the disease is found more often in men than in non-pregnant women. Pregnant women seem to be more susceptible to the serious form.



Floating freely in clouds of dust, the tiny cocci spores enter the body when they are inhaled. Most never get anywhere. The body’s wonderful defense system works too well: the spores get caught in sticky mucus inside the air tubes and are moved back up into the throat where they are either spit out or swallowed harmlessly. But some few cocci spores do continue the invasion. They work their way down the air tubes to the end of the passage: the little air sacs of the lung, where the air ends up when it is inhaled.

Deep in the lung, the spores begin to grow. They develop into pods that are filled with even tinier seeds. The pods burst open, the seeds pour out and spread in the lung and sometimes to other parts of the body. And wherever the spores settle down, the body reacts with inflammation. In the lungs, little patches of inflammation develop around the spores. Cavities or scars may result, and eventually deposits of calcium. When the spores stay in the lungs, the disease is said to be in its primary form. When the fungus spreads throughout the body—to the internal organs, bones, brain, and even the skin—cocci is in its disseminated form.



Perhaps as many as 60 to 70 percent of all people infected with cocci develop no symptoms at all. Some 30 to 40 percent do get sick—usually within one to three weeks after the cocci spores invade the body. Fever may go as high as 104 degrees. There are usually aches and pains and a cough. A week or two after the fever develops some patients get a rash that resembles the measles. There may also be tender red spots on the sins and pains in the joints. Usually symptoms disappear within a month or so, though full return of energy may take some months.

The disseminated form of the disease is a great deal more serious—with very high fever and extreme fatigue. It has been estimated that about one percent of white patients develops the disseminated form of the disease. But in ten to twenty percent of dark-skinned patients, cocci progresses to its disseminated form. It can be fatal.



Usually diagnosis is made on the basis of one or more of the following three types of tests: recovery of the cocci organisms from sputum (phlegm) or some other body fluid; blood tests that reflect the body’s reaction to the presence of the fungus; and skin tests. Many people without the disease may have a skin reaction. In some cases a biopsy may be needed.

These tests are quite reliable, but they may fluctuate according to the stage of the disease. The tests are not positive in every case of cocci. In some instances, the diagnosis may rest on circumstantial evidence, particularly for people living in an area of the Southwest where much cocci is found. In most cases, however, these tests are helpful.

Chest X-rays reveal some of the abnormalities associated with cocci, but the shadows may be mistaken for those of tuberculosis or some other lung disease.



Patients suffering from the flu-like symptoms of cocci in its primary form will probably be sent to bed by the doctor. Symptoms, such as cough and fever, will be treated. For the disseminated form of the disease, a variety of drugs are now available. Occasionally surgery is recommended to remove a diseased portion of the lung, bone, or skin.



There are many mysteries—yet unraveled—about cocci. And better methods both to prevent and treat the disease remain to be found. Simple avoidance of infected areas is probably best for newcomers among black, Mexican, and Filipino adults. Those who have lived there since childhood may well have developed a kind of immunity to the disease that newcomers do not have. Methods for the control and sterilization of dust are being studied and improved. Some research, including work on a vaccine, is now being done on ways to make people immune to cocci.



Anyone living or traveling in the Southwest United States should be aware of cocci and suspicious of flu-like symptoms—fever, aches and pains, and a cough. These may disappear in a day or two without treatment; on the other hand, the symptoms might indicate serious illness such as flu or cocci.