No-see-ums, also known as biting midges or sand flies, are not known to transmit pathogens causing human disease in the United States. However, they can infect certain animals with significant viruses.
While these tiny insects are a nuisance due to their painful bites, their primary role in disease transmission in the U.S. is limited to livestock and wildlife.
Diseases Transmitted by No-See-Ums to Animals
No-see-ums are vectors for several diseases that affect various animal species. These diseases can have considerable impacts on agricultural and wild animal populations.
The primary diseases they transmit to animals include:
- Bluetongue Virus: This viral disease primarily affects ruminants like sheep, cattle, goats, and deer. It can cause fever, swelling of the face and tongue, lameness, and hemorrhages.
- Epizootic Hemorrhagic Disease (EHD) Virus: Similar to Bluetongue, EHD mainly affects deer, causing high fever, extensive hemorrhages, and significant mortality in susceptible populations. It can also affect other ruminants.
Below is a summary of the diseases carried by no-see-ums and the animals they typically affect:
| Disease | Affected Animals | Description (Key Symptoms) |
|---|---|---|
| Bluetongue | Horses, Cattle, Deer, Sheep, Goats | Characterized by fever, facial and tongue swelling, lameness, and oral lesions. The tongue can turn blue in severe cases, particularly in sheep. |
| Epizootic Hemorrhagic Disease | Primarily Deer (e.g., White-tailed Deer), Cattle | Causes high fever, extensive internal hemorrhages, swelling of the head, neck, and tongue, and often leads to death. Affected deer may be found near water sources as they seek to alleviate fever. While cattle can be infected, they usually show milder symptoms than deer. |
It's important to note that while no-see-ums can be quite bothersome to humans due to their bites, the direct health risk of disease transmission to humans from these insects in the United States is considered negligible.
