There are four life stages of the flea and it is important to know how to break this life cycle in more than one place. This two-step approach provides the most rapid control and the least resistance to flea control agents in future flea generations.
The Flea Egg (They look like rice):
At any given time about one third of the flea population in someone’s home is in the egg stage. The adult female flea lays up to 50 eggs daily. The eggs are laid on the host where they fall off to hatch in the environment. Eggs incubate best in high humidity and temperatures of 65 to 80 degrees Fahrenheit. (18.3-26.6 Celsius).
The Flea Larvae:
At any given time about 55% of the fleas in someone’s home are in the larval stage. Larvae are like little caterpillars crawling around grazing on the flea dirt that is generally in their vicinity. Flea eggs and flea dirt both fall off the host. When the eggs hatch, there is a bounty of food prepared lovingly by all the host’s fleas waiting for the hatchlings.
The time between hatching and pupating (i.e., the time spent in the larval stage) depends on environmental conditions. It can be as short as 9 days.
Larvae are killed at 95 degrees. This means that they must live in some area (like shady outdoor areas or indoors) where they are protected from summer heat.
The Flea Pupae:
By this life stage most young fleas have been killed off by an assortment of environmental factors. Only 8% make it to the pupal stage but, once they have spun cocoons, they are nearly invincible. The cocoon is sticky and readily picks up dust and dirt. Inside the developing cocoon, the pupa is turning into the adult flea that we are familiar with. They are especially protected under carpet, which is why carpet has developed such a reputation as a shelter for fleas.
The pupa can remain dormant in its cocoon for months, maybe even up to a year as it waits for the right time to emerge.
The Unfed Adult Flea:
After the pupa develops, it does not automatically emerge from its cocoon. Instead, it is able to remain in the cocoon until it senses a nearby host. The mature pupa is able to detect the vibrations of an approaching host, carbon dioxide gradients, and sound and light patterns. When the mature pupa feels the time is right, he emerges from the cocoon, hungry and eager to find a host.
An unfed flea is able to live for months without a blood meal but during that time it is aggressively using all its powers to locate a host. Once it finds a host, it will never purposely leave the host.
The Fed Flea:
After the adult flea finds a host and takes its first blood meal, metabolic changes occur that alter the flea forever. The flea is now called a fed flea and, if separated from its host, will die in only a few weeks without a blood meal. The female flea begins to produce eggs within 24 to 48 hours of her first blood meal and will lay eggs continually until she dies.
The average life span of the adult flea is 4 to 6 weeks, depending on the grooming abilities of the host.
ON AVERAGE, THE TIME PERIOD FROM EGG TO ADULT FLEA
IS ABOUT 1 WEEK.
Treating Flea Infestations:
As outlined above, fleas can be a rather hardy and pesky parasite to deal with. That is why preventing fleas is much easier than treating them. However, if your pet has become infested, the best way to win the war against fleas is to direct treatment at more than one of the life stages of the flea. Realize also that you will be finding fleas for 1-2 months and this does not indicate product failure!
Adult fleas are only the tip of the iceberg of the problem, however, using products to sterilize and kill this stage of the flea can help reduce the numbers dramatically. Products like Frontline Plus use a drug that is an adulticide (kills the adults) and an insect growth regulator which sterilizes the female fleas so that their eggs should not hatch. The product also helps to kill the larval stage as well. These products should be started and utilized monthly to help as the larvae and pupae emerge into adult fleas later. If the infestation is bad, then an additional product to help control the adult fleas will be needed. Products such as Comfortis or Nexgard are fast-acting adulticide treatments. They are pills that start killing the adults fleas within 30 minutes of ingestion. This does not give the female flea time to lay eggs and therefore reduces the flea burden significantly.
If there is a significant infestation, then treating the environment may be needed. The yard can be treated with Virbac yard spray or Bayer Advanced Complete Insect Killer. These can be used every 2-4 weeks as needed. Be sure to keep your pets out of the yard until the product has had ample time to dry (at least several hours). Homes can be treated with Knockout ES area treatment. Your pet's bedding should be laundered along with any washable pillows or other objects your pet spends time on and any washable toys your pet plays with. Again, pets will need to be kept out of the area for several hours to allow product drying. When vacuuming, throw the bag or waste away in an outside trash can.