Bug FAQDeer Ked
Lipoptena cervi · Order: Diptera · Family: Hippoboscidae
Also called: Deer Fly
Source: Wikipedia
Deer keds are tiny, brownish flies about 5 to 7 mm long that live on deer and other cervids, feeding on their blood. They may occasionally bite humans, producing mild to allergic reactions, and have been found with bacteria that cause anaplasmosis and Lyme disease, but it is unclear if they can transmit them.
Source: Wikipedia
How to recognize it
Their bodies are flat and elastic, which makes them hard to pull off hair or clothing.
Source: Wikipedia
Size
Adults measure only 5 to 7 mm in length and are brownish in colour.
Source: Wikipedia
Is it a pest in the house?
The main problem for people is the nuisance of removing keds from hair and clothing. On rare occasions they may bite humans, causing reactions that range from unnoticed to allergic.
Source: Wikipedia
Does it bite or sting?
Bites can be mild or trigger strong allergic responses in some people. They have been found carrying Anaplasma phagocytophilum and Borrelia burgdorferi, though it is not known if they can transmit these pathogens.
Source: Wikipedia
How to get rid of it
When they reach a host, they shed their wings and burrow into the animal’s fur.
Source: Wikipedia
Where it lives
They are common in temperate parts of Europe, Siberia and northern China. They have also become established in several eastern U.S. states, including New Hampshire and New York.
Source: Wikipedia
What it eats
Both male and female deer keds feed on the blood of their hosts.
Source: Wikipedia
Where it is found in the US
Recorded in 12 of 51 states and DC. Most records: New York, Pennsylvania, Massachusetts, Vermont, Connecticut, New Hampshire, West Virginia, Rhode Island.
Darker = more records. Counts are museum and citizen-science records, not population size.
Source: GBIF
Status: introduced in North America; introduced in Canada; introduced in United States. Source: iNaturalist
Months it is reported in the US
Source: GBIF
More photos
Questions people ask
Can deer keds bite humans?
Yes, they can bite people, but bites are rare and usually cause only mild or allergic reactions.
Source: Wikipedia
How do I remove deer keds from my clothing?
Because their bodies are flat and elastic, they can be difficult to pull off; shaking or brushing the fabric while wearing gloves usually helps.
Source: Wikipedia
Same family (Hippoboscidae)
Sources
- Wikipedia: https://en.wikipedia.org/wiki/Lipoptena_cervi
Look it up elsewhere: GBIF · iNaturalist · BugGuide · ITIS · Wikipedia
Text written 2026-10-22 from the sources above and checked sentence by sentence against them. Data fetched 2026-10-22.