Risks of valley fever (coccidioidomycosis)

Learn about the risks of valley fever and who is most at risk..

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What are the risks of getting valley fever?

Anyone can get valley fever. However, it is more common in people who are:

  • 60 years and older
  • living or travelling in areas where the Coccidioides fungi are found in the soil

The risk of getting sick from valley fever is generally low for most travellers. It is more common among those who live in certain places of the world where the fungi are found. These people are more frequently exposed to the fungi. 

Places where the fungi are found are:

  • some areas of the Southwestern U.S., including:
    • Arizona
    • California
    • Nevada
    • New Mexico
    • Texas
    • Utah
  • south-central Washington State in the U.S.
  • Mexico
  • Central America
  • South America

However, you may be at a higher risk if you take part in some outdoor activities in these areas.

These activities, which disturb soil and dust, include:

  • farming
  • construction
  • landscaping
  • gardening
  • any digging, such as for fossils or bones
  • recreational activities, such as dirt biking

You can also be exposed to the fungi during dust storms or earthquakes.

Who is most at risk?

Some people may be at higher risk of having severe infections. You are most at risk if you:

  • have a weakened immune system (your body cannot fight disease easily) because you:
    • have either the human immunodeficiency virus (HIV) or acquired immune deficiency syndrome (AIDS)
    • have had an organ transplant
    • take certain anti-inflammatory medications, such as:
      • corticosteroids
      • tumor necrosis factor-inhibitors
  • are pregnant
    • the highest risk is in the third trimester of pregnancy
  • are diabetic

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