Many people start to itch when they talk about fleas. This is the most important characteristic of fleas. They are tiny creatures that jump over easily, especially in pets. This itching is caused by the biting of the fleas, because they can only survive by feeding on the blood of their host. Fleas therefore also fall under the category of pest insects.
The scientific name of fleas is Siphonaptera or Aphaniptera. Fleas officially belong to the winged insects, but despite that they have no wings. Their way of working and living resembles that of the tick, but the tick belongs to the arachnids and is therefore not a family of fleas.
Species of fleas
Worldwide there are about 2,500 different species of fleas. In the Netherlands and Belgium there are about 50 different species known. The best known fleas live on dogs and cats and some species can also occur in humans. People with pets are therefore always at greater risk of coming into contact with fleas, all the more so because flea nests can nest under the carpet.
The cat flea is the most common flea in the Netherlands. It is not only active in cats, dogs and humans can also suffer from it. The cat flea is about 2 to 3 millimetres in size and has long legs so they can jump from one host to another. The cat flea can produce about 20 eggs a day with a maximum of 600 during its lifetime. Cat fleas can live to be 1 year old. The eggs are small and white and the larva grows into an adult flea in about 2 to 8 months. The food of the larvae consists of animal waste and the excrement of adult fleas. The cat fleas like to nest in places where a cat has its resting place, like a cat basket. Treating the cat with a flea agent that works well on the skin can greatly reduce a flea infestation.
Although there are many dogs living in the Netherlands, the dog flea is not very common anymore. It is more often the cat fleas that cause nuisance to dogs. The dog flea is 1 to 4 millimetres long and it is striking that the larva can grow longer than the adult, up to 5 millimetres. Larvae undergo a cycle of 4 stages: eggs, larvae, pupa to adult fleas. A characteristic of dog fleas is that they can jump up to 15 centimetres. A dog experiences more complaints when it is bothered by dog fleas than with cat fleas. In addition to annoying itching, the dog can suffer from redness of the house, hair loss, allergies and severe skin infections.
In Europe, the human flea has not been seen much. In other less developed and less hygienic parts of the world, human fleas are still fairly common. Adult human fleas are about 1 to 4 millimetres in length and have a long and fine snout to pierce human skin and drink blood. The human flea eggs of half a millimetre are laid on the body or in the room where the host is staying and hatch after about 2 weeks. People who suffer from these fleas are mainly bitten in the lower legs and ankles. The bites can be painful and carry a risk of transmitting diseases. This is because human fleas move easily from one body to another. Human fleas are also found on dogs, cats, monkeys, chickens and rats.
Living area of fleas
The presence of mammals and birds is a prerequisite for fleas to survive. That is why fleas occur all over the world. However, there are certain species of fleas that live on very specific animals and therefore have a relatively small habitat. Other fleas, such as dog and cat fleas, have a cosmopolitan distribution and can be found anywhere in the world.
Flea in the Netherlands
In the Netherlands, only fleas with a cosmopolitan distribution, such as cat fleas and dog fleas, are found. This is partly due to the many dogs and cats that are kept as pets in the Netherlands. We also know some fleas that live in the wild on e.g. birds, rats and hedgehogs.
Outer characteristics of fleas
Whatever the type of flea, all fleas are minuscule with dimensions between 1 and 5 millimetres. All fleas also have a flattened body. The colours vary from reddish brown to black and other colours or patterns are not known. Fleas have three legs on both sides, front legs, middle legs and hind legs where one can switch to another host.
The flea has a small head. Most fleas have a comb on the underside of the head. Under a microscope one can recognize the kind of flea by the comb. Some species of fleas don’t have a comb. The mouth of the flea consists of different protuberances. There is a protrusion that pierces the skin and a protrusion with a tubular structure that can suck blood. In a groove in the head the flea has two antennae. These are only removed from the groove when it uses the antennas. In a fur of an animal, protruding antennas are annoying.
The chestpiece consists of 3 segments. Each segment has a pair of legs. The first segment is placed so far towards the head that it looks as if the front legs are attached to the head. Most fleas also have a comb on the chestpiece. This comb serves to reduce the resistance when walking over a coat.
The tough abdomen of the floor is protected by belly plates. The abdomen is very important for a flea because the abdomen contains the most important organs, such as the digestive system, the sexual organs and the respirator.
Fleas only live on and from hosts such as humans, mammals and birds and are therefore also seen as a parasite. Larvae, on the other hand, are known as nest parasites and live in the sheltered environment of a nest or resting place of the host.
What do fleas eat?
Fleas are excluded from the blood of their hosts. However, in the absence of a host, a flea can go without food for a longer period of time. The larvae of the flea cannot suck blood and therefore feed on undigested remains of blood from the stools of adult fleas. The larvae can also eat the eggs and other larvae.
Enemies of fleas
Planting and lifespan
Fleas mate very short through the back of the body. Immediately after mating, the eggs are produced in the female’s body. Normally a flea develops from egg to larva and in some cases from pupa to adult flea. The lifespan of a flea strongly depends on factors such as temperature and humidity. As a result, a flea can live for several months up to a year.
Nuisances and illnesses
Having fleas in your house is very annoying. This is because fleas can be found in every nook and cranny of the house. A popular place for fleas is under the carpet and a rug. In the past, fleas were the cause of outbreaks of bubonic plague, for example. Because of the hygienic living conditions of the people, this is excluded nowadays. However, fleas can cause tapeworms, but the chances are nil.
Fleas are especially active in the autumn and sometimes come at you with hundreds at a time. In such a case you want to leave professional flea control to a pest controller. They know which products help best and where to apply pesticides. It is advisable to be there quickly, because you never know if the pest is getting bigger. There have been cases of people literally fleeing their homes with so many fleas. In this case, a warned person counts for two.