Blood-sucking fly causing infections across the US

UNDATED (CNN/CNN Newsource/WKRC) – A blood-sucking fly has caused infections across United States.

Sand flies are tiny tan flies, which are about the quarter of the size of a mosquito. They can cause an infectious disease called leishmaniasis, which according to the Cleveland Clinic, is an infection with Leishmania, which are parasites found in tropical and subtropical regions of the world that can cause severe ulcers on the skin, which can be fatal if it infects your internal organs.

They’re most active at night and so small that they can slip through the average mosquito nets on tents or window screens.

The Centers for Disease Control and Prevention said they’ve detected leishmaniasis in a number of tissue samples from patients who said they have not traveled outside the United States.

Severe cases can be fatal if left untreated. Sand flies capable of carrying the parasite that can cause the infection can be found in a number of southern and southwestern states.

Experts said they’re still working to learn more about the bugs, but said they can be repelled by bug sprays containing deet.

Those who have new skin sores or a bug bite that don’t go away were encouraged to see a doctor.