Recognize Fleas: 5 Typical Signs of Fleas


Before it comes to seriously combat a potential flea infestation, you should first be sure that it is actually fleas you have to fight. There are some hints and typical signs of fleas that you can easily check.

Fast Facts: Signs of Fleas

  • Frequent scratching
  • Recognize flea bites on humans or pets
  • Recognize living fleas
  • Droppings
  • Flea larvae

Of course, you find more detailed information about the different signs of fleas in this article. You can also use the table of contents further below for quick navigation.

To easily detect fleas, there are also a few small but helpful tools. These are listed for each sign’s subsection and also again at the end in the summary section.

Disclaimer: I am not a doctor. For medical advice as well as accurate diagnosis and treatment always contact the doctor you trust most!

How do I recognize a possible flea infestation?

1) The trigger: frequent scratching

Frequent scratching is probably the triggering indicator, after which many go to search for the cause of their own or their animals itchy bites. Because at first, you often can’t be sure which insect might be the villain.

In addition to fleas and mosquitoes, bed bugs and many other biting or stinging insects come into question.

In addition to your own itching after flea bites, you can also watch a frequent scratching behavior of your pet, which may point to a flea infestation.

Itchy bites don’t only drive us, humans, mad…

2) Recognize flea bites on humans or pets

Fleas usually prefer a particular host animal such as a dog, cat or sometimes also a human. Nevertheless, it also happens that a dog flea or cat flea bites a person.

In any case, flea bites are a very annoying remnant as they can cause severe itching.

Nobody likes that.

Short info: fleas and diseases - click to expand

It is also possible that fleas transmit diseases. In addition to larvae of tapeworms, bacteria can also be transported by flea bites, which can cause typhus fever, often confused with typhoid fever. The typhus fever is also called war plague or putrid fever.

The rat flea is considered to be the main carrier of the plague, which left millions of people dead by the end of the 19th century. Perhaps the most glaring example is the plague epidemic that raged in Europe in the mid-14th century and is still known today as the “Black Death” (about 25 million dead).

The transmission risk of diseases caused by fleas is currently extremely low, at least in Europe.

a) Flea bites on humans

Does it itch already? But you still do not know why then you can take a closer look at the bites on your body.

Signs of Fleas - Flea Bites on Humans
Signs of Fleas: Flea Bites on Humans – Photo: Saaaaa / Depositphotos

The flea bite itself remains unnoticed for quite a while. Only after the flea bite the itching develops, as the secretion in the saliva of the flea contains a kind of painkiller and blood coagulation stopper.

Typical of flea bites on humans are closely spaced reddened wheals. Flea bites are often in rows because the flea has difficulties to decide and, thus, tries different spots for his meal.

b) Flea bites on pets like dog and cats

Fleas are not so easy to recognize on dogs or cats because of the fur. However, a frequent scratching at different places strongly suggests a flea infestation. As with humans, the itching can also drive an animal “mad”, so it desperately tries to get to the itchy spots and scratch/bite them.

Also, dog flea bites or cat flea bites are recognizable. For this purpose, the fur can be examined by hand or with the help of a flea comb for flea bites, living fleas, and flea feces.

3) Recognize living fleas

Fleas are very small, brownish to red-brownish insects with a laterally flattened body shape. Despite their very small size (about 2.5mm), they are basically visible to the naked eye without further aids, even if a magnifying glass helps (unless they have jumped away before the closer examination).

Photo: goldfinch4ever / depositphotos

Human fleas are among the “nest fleas” and prefer to hide near the sleeping place of their victim. These include mattress, bedstead, linens, dessert cabinet, rugs, furniture and similar items near the bed. In most parts of Europe, however, human fleas are relatively rare and people are more likely to be affected by other fleas such as those of pets.

To detect living fleas on dogs or cats, it is best to examine the fur with a flea comb. Because dog and cat fleas are among the “fur fleas”. Popular places for fleas are the head and neck area as well as the hind paws.

Video: How to detect fleas on your dog or cat

4) Signs of fleas: Droppings

Another indication of a flea infestation are the excretions of fleas. The flea excrement can be identified by small black dots. They look like crushed black pepper.

To be on the safe side, these supposed traces of feces can be rubbed into a piece of white paper. If the grains stay black, they are normal dirt crumbs. If the paper discolors brownish to reddish, this indicates that it could be fleas.

Using a flea comb, you can examine your pet for these traces. Another option is to walk with white socks over the carpet. If black spots remain on the white socks, they could be fleas or their excretions.

5) Flea eggs, flea larvae, and flea pupa

Also, flea eggs and flea larvae can indicate a flea infestation. Provided you can recognize them. Female fleas can lay dozens of flea eggs a day, from which the flea larvae hatch a few days later, depending on the prevailing conditions. The flea larvae have a size of 1-2 mm.

The flea larvae pupate in a silky cocoon, which they leave after a few days or weeks depending on the conditions as an adult flea. But this process can sometimes take up to half a year. In this condition, fleas are particularly difficult to combat.

Recognize fleas: Life cycle of a dog flea – Photo: kotjarko / fotolia

Useful tools for the flea check

  • Flea comb
  • White paper
  • Wear white socks in the house
  • Magnifying glass
  • Flea trap


Cover photo: goldfinch4ever / depositphotos

Leave a comment

2 × three =