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How Bad are Fleas for Humans?

Flea on human skin

Fleas are bad for humans in many ways. They spread many diseases in your house, and they can cause a lot of health risks to humans. Therefore, you must take every measure to eradicate fleas when you locate fleas in your house or on your pets.

Flea bites rarely ever leave a harmful effect. They leave a mildly irritating effect for a short period. However, flea bites might be dangerous and spread a fatal or serious disease. Keep reading to know more about the bad effects of fleas on humans.

How Harmful Are Fleas to Humans?

Although flea bites rarely leave a mild irritation or harmful effect on human skin. But some of the bites may spread a dangerously fatal or serious disease in humans.

Do Fleas Bite Humans?

Close up of flea bites on human skin

Fleas have been around for as long as anyone can remember, and they have been a health hazard to humans and pets all this time. If you have fleas in your house, it is most likely that your pet has been affected by fleas for a long time, or they have received flea medication.

Now the question that arises is, do fleas bite humans? The simplest answer to this question is yes! Fleas bite human beings when they cannot find any other host to feed on.

What Do Fleas Like to Eat?

Shiba Inu sitting in a field scratching

Fleas are blood-sucking insects. They like to feed on the blood of mammals to lay eggs. They feed on blood and lay eggs within 36-48 hours.

Once the flea eggs hatch, they feed on the flea dirt left behind by the parent flea. They normally do not require blood until they reach adulthood. However, female fleas need to feed on blood to reproduce. Fleas can grow and reproduce very rapidly.

How Do Fleas Bite?

Toy wind up teeth isolated on a white background

Fleas feed on blood and prefer the blood of animals. Pets and other animals are included, but they are also eager to feed on people. Fleas bite humans to access the blood arteries beneath the skin, and their bodies are designed to do so.

The first thing you should learn is how flea mouthparts operate. These parasitic insects have jaws that can puncture the skin and discover blood arteries, ensuring that blood flows so that they may eat.

The mouth of the fleas is divided into three parts which act like needles. The two upper parts pierce the host’s skin and reach deep down to the blood vessels. They hold open the blood vessels, and then the third or the enter part digs into the blood vessel and starts to suck on the host’s blood.

When they do this, their salivary glands open up and employ the same mouthparts used for eating to inject an anticoagulant, preventing the blood from clotting and flowing down into their body.

What is the best way to get rid of fleas off of a human? Check out our post “How to Get Rid of Fleas on Humans” to learn more.

How Are Fleas Dangerous for Humans?

View of a child's legs while in bed covered in insect bites

Fleas might be considered harmless to humans and animals most of the time, but they can cause a lot of skin allergies and skin problems in humans and animals. They can also leave behind some diseases and some of the most dangerous ones are discussed below.

Murine Typhus

A rat sitting on a piece of wood

This type of disease is usually spread by the fleas that rats carry. However, some cats that come in contact with the fleas that contain this disease can also spread it in your house. Humans usually get typhus from flea bites. The fleas usually defecate simultaneously when they bite.

Rickettsia typhi, a bacterium found in feces, enters the body through the bite wound or a person rubbing the bite region. Headache, fever, nausea, and bodily pains are all symptoms of typhus. Five to six days following symptoms, you may notice a rash on your torso that spreads to your arms and legs.

According to the Texas Department of State Health Services, if you suspect you have murine typhus, you should contact a doctor as soon as possible. Antibiotics can treat the sickness, but you may need to be hospitalized if you wait too long. If left untreated, the condition might last for months.

Mycoplasma Haemofelis

Vet listening to an orange cat's chest with a stethoscope

M. haemofelis is a bacteria that can cause severe anemia in infected cats. It can also be transmitted to humans through flea bites. Symptoms of infection include fever, fatigue, and chest pain.

If you think you or your pet may have been exposed to M. haemofelis, it is important to immediately see a doctor or veterinarian. Early diagnosis and treatment are essential for preventing serious health complications.

Is there a bug spray to get rid of fleas on humans? Check out our post “Bug Spray for Fleas for Humans” to learn more.


White tapeworms against a black background

Tapeworms are most commonly transmitted to humans and pets through the ingestion of fleas. Fleas can carry the eggs of tapeworms in their gut, and when another animal ingests the eggs, they hatch, and the tapeworms begin to grow.

Tapeworms in pets are not contagious to humans, but swallowing an infected flea can lead to tapeworms in humans, especially children. Fortunately, it is easy to treat tapeworms by using praziquantel. This medicine is injected into humans and is often given orally to felines.

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Please note: We are not veterinarians and you use our advice at your own discretion. We always recommend that you consult your veterinarian whenever you have health-related conditions your furbaby is facing. With that in mind, as pet parents ourselves, we wish nothing but the best for your pet and their healthy and happy lives.