The National Academies: What You Need To Know About Infectious Disease

The National Academies

What You Need To Know About Infectious Disease

Histoplasmosis

Histoplasma capsulatum, a fungus that grows in soil and other material contaminated with bat or bird droppings, is the cause of histoplasmosis. When contaminated soil is disturbed, spores become airborne and can be inhaled. The spores cannot, however, be transmitted from one infected person to another. Found throughout the world, the fungus is endemic in some areas of the United States, primarily the Mississippi and Ohio River Valleys. It has been found in bird roosts, poultry house litter, caves, and areas where bats live.

Symptoms
In most cases, infection does not cause any symptoms. If symptoms do occur, they will appear between 3 and 17 days after exposure, with the average timeframe being 10 days. If acute respiratory illness occurs, it results in fever, chest pains, a dry cough, and an overall feeling of illness. A chest X-ray may reveal distinct patterns on the lungs. Chronic lung disease, which looks like tuberculosis, can gradually worsen over months or years. When organs other than the lungs are affected, the disease is called disseminated histoplasmosis, a form that can be fatal if not treated. People with AIDS, cancer, or compromised immune systems caused by other illnesses are at the highest risk for this form of the disease.

Treatment
Mild forms of the disease rarely require treatment. In cases of acute histoplasmosis and in all cases of chronic and disseminated disease, antifungal medications are used. If re-infected, past infection typically provides partial protection from symptoms.

Prevention
The best way to prevent the disease is to avoid places that might harbor the fungus, such as locations with accumulations of bat or bird droppings. If you must work in areas where the fungus might be present, consult the National Institute for Occupational Safety and Health’s publication Histoplasmosis—Protecting Workers at Risk or call the CDC at 1-800-CDC-INFO for safety precautions.

Sources:
http://www.cdc.gov/nczved/divisions/dfbmd/diseases/histoplasmosis/#what
http://www.mayoclinic.com/health/histoplasmosis/DS00517

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What do you know about infectious disease?

“Antibiotic resistance” refers to:

  • Sorry, that’s incorrect.

    “Antibiotic resistance” refers to the ability of bacteria to resist the effects of an antibiotic. Antibiotic resistance occurs when bacteria undergo a genetic change that reduces or eliminates the effectiveness of drugs or other agents designed to cure or prevent infection.

  • Sorry, that’s incorrect.

    “Antibiotic resistance” refers to the ability of bacteria to resist the effects of an antibiotic. Antibiotic resistance occurs when bacteria undergo a genetic change that reduces or eliminates the effectiveness of drugs or other agents designed to cure or prevent infection.

  • Correct!

    “Antibiotic resistance” refers to the ability of bacteria to resist the effects of an antibiotic. Antibiotic resistance occurs when bacteria undergo a genetic change that reduces or eliminates the effectiveness of drugs or other agents designed to cure or prevent infection.

Infectious Disease Defined

Natural Selection

The process by which certain heritable traits that contribute to the survival and reproductive success of an organism become more widespread within a population over successive generations.

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