Black Fly

The "Koon" or commonly known as the "Black Fly" is a small black insect, similar to a mosquito but with a shorter, thicker body. It bites painfully and prefers humid areas or places near flowing water.
In general, the black fly (Koon) is most prevalent during the rainy season to the early part of winter, as this period has flowing water and high humidity, which are ideal for egg-laying and growth.
Characteristics of the Black Fly (Koon)
- Very small, about 1–5 millimeters in size
- Dark black or gray color with a short, thick body, resembling a tiny fly
- One pair of clear wings; can fly, but not very fast
- The body is curved and bulging
- Female black flies bite and suck blood to use for egg-laying
- Often found near flowing water, such as streams, waterfalls, or damp areas
Key Observation: When bitten, it immediately feels painful and usually causes swelling, redness, and itching, which is more intense than a mosquito bite.
Symptoms When Bitten by a Black Fly (Koon)
- Immediate pain when bitten (unlike mosquitoes, which are often not felt right away)
- Swelling, redness, and intense itching
- Some people may experience prolonged swelling, hardening, or inflammation for several days
- In severe allergic reactions, there may be significant swelling, fever, or headaches (though this is rare)
Difference from Mosquitoes: Black flies have a shorter, thicker body, fly more slowly, and cause immediate pain when bitten. They are more active during the daytime, unlike mosquitoes that typically bite at night.
How to Prevent Black Fly (Koon) Bites
- Wear long-sleeved shirts and long pants when near streams, waterfalls, or damp areas.
- Apply insect repellent to exposed skin.
- Avoid areas with flowing water during peak fly activity, especially during the daytime.
- Close windows with screens or use mosquito nets if staying in high-risk areas.
source : Ruampat Chachoengsao Hospital
**Translated and compiled by ArokaGO Content Team
Independent Writer
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