Leishmaniosis is a parasitic disease that occurs in the Mediterranean basin and in South America and can affect dogs and people , being one of the most well-known parasitic diseases in humans . It is transmitted through the bite of a sandfly , a type of mosquito that bites mammals and birds. In addition, other animals (there are up to 70 species), such as hares, rats or opossums, act as reservoirs, that is, they are intermediaries in the transmission of the disease.
What is the body of the leishmaniasis mosquito like?
The sandfly that transmits leishmaniasis is a small insect , about 2-3 mm long, that does not emit a buzzing sound. It is light brown to yellowish brown and has a hairy body and wings, long thin antennae, and a proboscis that is longer than the head and is used by females to suck blood. The wings adopt a 45º angle when the mosquito is biting perched on the animal’s skin. There are more than 90 different species of sandflies that transmit leishmaniosis.
How does the leishmaniasis mosquito act?
Its activity takes place from sunset to sunrise , and the rest of the day is hidden in dark and cool places. It is more common in areas with vegetation and in places where minimum temperatures do not usually drop below 15ºC . For this reason, fluctuations in temperature can greatly affect the development of the parasite inside the body of the mosquito, causing it to be transmitted in areas where the disease did not exist before. In addition, it also needs moisture for the eggs to survive; puts them in cracks, holes, animal burrows, and tree roots . After the rain spikes, populations are reduced due to lack of daytime roosting sites for adults and because heavy rains lead to the death of immature stages. It cannot fly if there is a strong wind and the flight distance is very short; Forages for food no more than 50 meters from its breeding site.
What life stages does the leishmaniasis mosquito have?
Its life cycle goes through four stages: egg, larva, pupa and adult. One week after sucking blood, the female lays about 60-80 long, deep brown eggs in moist places rich in organic matter. The eggs hatch releasing the larvae, only half a millimeter long, a week after laying. The pupa is light yellow and retains the cuticle of the larva. The adult is fully developed about 2 months after the eggs are laid.
How does the leishmaniasis mosquito transmit the disease?
To bite the dog, the female sandfly, which needs to suck blood to feed and form eggs, lands on its skin. The transmission of leishmaniasis takes place through this bite when the sandfly has previously bitten an infected dog . Each female sandfly usually bites 3 or 4 times and then dies, usually before they are two weeks old.
How can we control the leishmaniasis mosquito?
The usual thing is to resort to fumigating houses and animal shelters with insecticides. And if it is known where the mosquitoes rest, it will also be useful to spray these places.
As for prevention in dogs, it is best to use authorized insecticides or repellents (collars or sprays, for example) during periods of sandfly activity. It is also important to bear in mind that if we introduce infected dogs into leishmaniosis-free areas, we must take extreme precautions against sandflies, since we will have a real risk of spreading the disease to previously free areas. In this sense, the application of repellents is essential to control the disease collectively.
And finally, it is also interesting to remember that dog walks should preferably take place in areas far from rivers, stagnant waters, swampy areas, etc., and during the day, trying to avoid the hours between sunset and sunrise, since during these hours mosquitoes are more frequent.