It is the feeding method of those who feed on blood. It represents a form of ectoparasitism, in most cases, and endoparasitism, in tapeworms, for example. Among the most notable cases of blood-sucking are mosquitoes, of which only females are blood-sucking; ticks, fleas, lice, some bats (Desmodontinae subfamily) which are called vampires or leeches.
Blood as tissue has chemical properties that make it a suitable form of food for certain species. Note that the properties of blood are lost when the animal dies, so blood-sucking animals feed on the blood of live animals. This peculiarity is very unique, since the animal attacked by another blood-sucking animal must not die, otherwise its blood would not serve as a food source.
Although the species of blood- sucking animals are different, they all have similar morphological characteristics: a powerful oral device to pierce the skin of their victims, a secretion system that allows the blood of their prey to clot, and a very precise olfactory system that facilitates the detection of blood in other animals.
Hematophagy is considered a form of parasitism and it should be noted that only females feed on blood as they need blood for protein to perpetuate their species.
Some anticoagulant drugs have been derived from knowledge of the chemicals of some blood-sucking species, especially leeches.
Hematophagy is not simply a curiosity of the animal kingdom, but it is relevant because it represents a risk to human health. This is due to the fact that blood-sucking animals are often the cause of some infectious diseases (medically considered a disease vector).
There are many infectious diseases related to these blood-feeding animals: rabies, malaria, Lyme disease, Chagas disease, or dengue. One of the blood-sucking mosquitoes that can trigger an infectious process is Aedes Aegypti, which is the carrier of the dengue virus, yellow fever or malaria and Zika fever.
