PHOENIX - Health officials are issuing an alert for people who were caught in the huge dust storm last week.
The Arizona Department of Health Services says thousands of people could have been exposed to Valley Fever.
You may remember the storm rolled in mid-morning. People were away from their homes or at school and some were caught outside in it.
Doctors say the symptoms of Valley Fever usually start showing up 1 week to 3 weeks later.
The fungus that lives in the soil is dangerous when it's kicked up by the winds and inhaled.
"There are some cases where Valley Fever can be disseminated which means it gets into other parts of the body, not just the lungs. Those cases are pretty severe for people. Lots of people with disseminated Valley Fever require hospitalization," said Jessica Rigler with the Arizona Department of Health Services.
Experts say see a doctor if you have developed a cough, if you feel tired or have a fever or night sweats.