Flea bite

A flea bite usually shows up as small, hard bumps with a distinct red centre point, bright red halo around a darker punctum, appearing immediately to within an hour. It peaks around within a day and generally lasts a few days; the itch can persist for weeks in sensitised people. Clusters of three or four, or short irregular groups is the usual arrangement.

How to tell it apart

Fleas jump from floor level, so bites concentrate below the knee — ankles and shins first. The mark is smaller and harder than a mosquito bite and almost always has a visible puncture point in the middle. Clusters of three are common, but unlike bed bugs the grouping is irregular rather than a neat line.

Where and when you meet it

Habitat: pet bedding, carpet pile, skirting boards, upholstery — the adult fleas you see are a small fraction of the eggs and larvae in the floor.

Across 1,727 verified US records in the GBIF biodiversity database, sightings of Ctenocephalides felis concentrate in June, August, September, October. That is the window when bites are most likely — it is observation data rather than a guess, and it shifts with latitude.

States with the most recorded sightings

• Oklahoma 335 records
• California 159 records
• Texas 118 records
• Minnesota 115 records
• Iowa 100 records
• Arkansas 91 records
• Georgia 70 records
• Florida 67 records
• Hawaii 67 records
• Illinois 53 records
• Maine 41 records
• Massachusetts 29 records

Record counts reflect where people report and identify specimens, not exact abundance. They are useful for ruling a species in, not for ruling it out.

Where it is recorded

Verified records from the GBIF biodiversity database across the seven countries we cover. A country missing from this table means we have no records for it, not that the species is absent.

What it means for you

If bites are below the knee and there is a cat or dog in the house, fleas are the first thing to rule out — including in homes where the pet has "never had fleas", because a single infested visit or a second-hand rug is enough. Bites that continue for weeks after treating the pet usually mean the carpet stage was never dealt with.

Associated illnesses in the US

• murine typhus (Gulf Coast, California, Hawaii)
• cat scratch disease bacteria carried between cats
• flea tapeworm (mainly in children who swallow a flea)

Most bites transmit nothing. What matters is the follow-up: note the date, and report any fever or rash in the following weeks to a clinician along with the fact that you were bitten.

Care at home

1. wash with soap and water
2. cold pack and an antihistamine
3. treat the pet and the home on the same day — skin treatment alone changes nothing

Preventing the next one

• year-round veterinary flea control for pets
• vacuum daily during an infestation and empty the canister outside
• wash pet bedding on hot wash weekly