Wuchereria bancrofti , or W. bancrofti , is the parasite responsible for lymphatic filariasis, popularly known as elephantiasis, which is a more common disease in regions of hot and humid climate, mainly in North and Northeast Brazil.
This parasite is transmitted through the bite of the mosquito of the genus Culex sp. infected, which releases infectious larvae into the person's bloodstream as they travel to the lymphatic vessels, resulting in an inflammatory response and the characteristic symptoms of lymphatic filariasis, such as swelling of the leg, arm or other body region where the parasite is present, fever and muscle pain, for example.
Understand what Filariasis is and how to recognize symptoms.
Life cycle of Wuchereria bancrofti
Wuchereria bancrofti has two evolutionary forms, the microfilaria and the adult worm. The microfilaria corresponds to the juvenile form of the parasite and is the form found in the bloodstream and lymph nodes, while the adult form of the parasite is present in the lymphatic vessels and produces more microfilariae, which are released into the bloodstream.
Wuchereria bancrofti has two life cycles, one in mosquitoes and the other in people. The Culex quinquefasciatus mosquito, when biting an infected person, inspires microfilariae, also called L1, which develop for a period of 14 to 21 days in the mosquito's intestine until the L3 phase and then migrate into the mouth.
When biting another person, the mosquito transmits the L3 larva, which migrates to the lymphatic vessels and develop until the L5 stage, which corresponds to the adult and sexual maturation stage. The L5 larva, after the incubation period, begins to release the microfilariae that are circulating in the blood.
How is the diagnosis
The diagnosis of infection by Wuchereria bancrofti is made through laboratory tests, since diagnosis through symptoms is, in most cases, difficult, as the disease can be asymptomatic or have symptoms similar to other diseases.
The laboratory diagnosis is made through the investigation of microfilariae in peripheral blood, it is important that blood collection be done at night, because it is during the night that the parasite is found in the highest concentration in the blood, allowing the diagnosis.
After collection, the blood is sent to the laboratory to be analyzed through the thick drop, which is a technique that allows the visualization and counting of microfilariae between blood cells. In addition, other diagnostic techniques can be performed, such as PCR and immunological tests to identify antigens or antibodies against the parasite.
Prevention and treatment
The prevention of infection by Wuchereria bancrofti is through measures to prevent the reproduction and bite of the mosquito responsible for the transmission of the disease, it is recommended to use musketeers, use repellents and avoid standing water, for example. In addition, it is important to invest in hygiene measures for the environment, as it is also possible to avoid mosquitoes.
Treatment for W. bancrofti should be done according to the doctor's guidance, and the use of Diethylcarbamazine is usually recommended for about 12 days. This remedy is the most suitable to combat this parasite, as it acts both against the adult worm and against the microfilariae. In some cases the use of Ivermectin may also be recommended, however this remedy does not work against adult worms, only against microfilariae. Learn more about treatment for Wuchereria bancrofti infection .
