Not an easy task: Tips for getting rid of fleas once they invade your home

Fleas can infect people, pets with disease-causing germs

Morphological characteristic of a flea depicted in the digitally-colorized scanning electron microscopic (SEM) image, 2017. Image courtesy Centers for Disease Control (CDC) / Ken Gage. (Photo by Smith Collection/Gado/Getty Images) (Smith Collection/Gado, Getty Images)

A flea is a very small insect that survives by feeding on animal or human blood.

Their bites can cause itchiness and irritation. Fleas can infect people or pets with germs that cause flea-borne typhus, plague, or cat scratch disease.

The lifecycle of a flea

General flea life cycle. (CDC)

Most fleas have four life stages: Egg, larva, pupa (in a cocoon) and adult.

According to the CDC, their life cycle can be very quick or last many months to years depending on the environment.

After adult fleas find a human host, they mate and begin laying eggs in the fur and surroundings of the host. Eggs will hatch in one to ten days depending on environmental conditions (temperature and humidity).

After hatching, fleas enter their larval stage. They are free-moving and feed on blood and flea feces in order to continue growing. Within five to 20 days of feeding on “flea dirt,” the larva spin a cocoon and enter the pupa stage. The cocoon protects them from insecticides for several days or weeks until the adults are ready to come out.

  • Insecticides will NOT kill fleas when they’re in cocoons!

Adult fleas will not emerge from the cocoon until they know there’s a host -- they become alerted to a host by movement or body heat. Adult female fleas begin to feed within a few hours of emerging and will begin to mate and lay eggs soon after.

Fleas find a host by detecting body heat, movement, and vibrations caused by movement and breathing. They prefer animals but will bite people when animals are unavailable.

Most common fleas in Michigan

Cat flea (L), Dog Flea (R) (CDC)

There are more than 2,500 flea species across the world and only 300 of those are found in the United States.

According to Michigan State University, the cat flea is the most commonly encountered flea species in Michigan. The dog flea is usually found on wild animals. Both species prefer dogs and cats as hosts, but they are found on a wide variety of other animals including rodents and livestock.

Both species are intermediate hosts of the dog tapeworm which is common in both dogs and cats. The tapeworm is transmitted when the animal ingests infested fleas. The tapeworm could infect children if they accidentally eat infested fleas.

If the weather is hot and humid, the cat flea can complete its life cycle in three weeks. Fleas transmit germs that cause diseases through feeding on hosts or through fecal contamination, when infected flea feces is scratched into an open wound.

Cat flea (Ctenocephalides felis)

  • This flea is the most common flea found on pets (including dogs) and other domestic animals in the United States.
  • It is capable of spreading plague bacteria, but does so inefficiently compared with ground squirrel or rat fleas.
  • Cat fleas do not voluntarily leave their host once they have hopped on.

Dog flea (Ctenocephalides canis)

  • Transmits: Aids in spreading Dipylidium caninum, a tapeworm commonly found in dogs and cats, but occasionally found in humans.
  • Despite its name, the dog flea is not a common flea of the domestic dog in the United States.

Read: Let’s talk about Michigan ladybugs: Why they’re in your home and why you should do nothing about it

How to kill them once they’ve invaded your home

Getting rid of fleas is not an easy task. Moderate to severe infestations will take months to control and require several very organized steps.

The CDC recommends following the following steps: Sanitation, pet treatment, home treatment and follow-up. For the first step, you’ll need to clean areas where fleas frequently breed. That includes washing bedding, rugs and pet bedding. You’ll have to vacuum and sweep your floors -- paying attention to the edges of walls.

Every pet in the home will have to be treated for fleas. Bathe them with soap and water, then comb them with a flea comb. Focus on the face and neck regions and the area in front of the tail. Soap will kill adult fleas. You can talk to your veterinarian about a flea control product for your pet.

You’ll want to treat your home at the same time you treat your pets. That keeps all treatments on the same timeline and helps disrupt the life cycle of the flea. You’ll want to do a follow-up treatment within five to 10 days after the first application. You’ll want to continuously vacuum and sanitize areas throughout the period to pick up remaining eggs and juvenile fleas.

More tips for flea control:

  • Wear a pair of white calf-length socks and walk around the house and keep track of the areas where the most number of fleas are observed on the socks. Fleas on the socks will most likely be newly emerged adults seeking a host.
  • Remember closets and other areas where cats like to spend time. Fleas will be most numerous in pet resting areas and other out of the way places where cats like tos pend time.
  • Both dogs and cats are very effective at removing fleas -- a researcher reported that up to 80% of the fleas removed by the host in two weeks time, which means focus your flea control on the environment where the pet lives and not only on the pet.


To prevent the development of flea larvae, you should use insecticides known as insect growth regulators or IGRs. They are synthetic compies of a substance that are present in developing insects and control the growth of the larvae. They interfere with normal development and kill the larvae. They have very low toxicity to mammals so they are safe to use around infants and small children.

The most widely available IGR for flea control is methoprene. Precor remains effective for up to four months, so you can treat your home three times a year to virtually eliminate flea problems. Before you apply Precor, you should thoroughly clean and vacuum your home to remove any debris that will prevent complete coverage of Precor.

After cleaning, apply the Precor spray to all floor surfaces, upholstered furniture (remove cushions and interior areas), pet sleeping areas, the bottom 18′' of floor length drapes. Move and treat under all furniture. Make sure all treated surfaces are completely dry, usually takes 2 hours, before you allow anyone back into the home. Wait two days before vacuuming the carpets toa allow Precor time to set up.

It does not kill pupae or adult fleas.

Where to check your pet for fleas. (CDC)

Tips for preventing fleas on your pets

The CDC said there are some things you can do to prevent fleas on your pet.

You can limit the amount of time they spend outside, limit their contact with stray and wild animals, bathe and brush them regularly, and check for fleas regularly.

You should talk to your vet about flea control products and treat your pet year-round in order to kill adult fleas and prevent new ones from hatching.

Flea collars alone are not effective. While some flea collars may help to keep fleas off the head and neck areas, the fleas usually stay in the tail and underbelly regions. Some pets may also develop an itchy rash from the flea collar.

Cats, kittens, and young dogs can become sick from sensitivity to the insecticide in the collars. They can also be dangerous if they get stuck in the pet’s mouth. So, if you do use them, you should use them with caution.

The Michigan Humane Society recommends using high-quality flea products or treatments. There are many newer flea repellent products in the market. Some are a pre-mixed, pre-measured liquid that you can place on your pet’s skin. It only needs to be applied once a month.

Read: Bed bug problems: What to do if you have them, how to check, how to prevent it

About the Author:

Kayla is a Web Producer for ClickOnDetroit. Before she joined the team in 2018 she worked at WILX in Lansing as a digital producer.