Filariasis is a very common disease on the tropical continent. About 1.4 billion people in 73 countries of the world are constantly at risk of this ailment. And about 40 million as a result of it have already become disabled.
This disease can cause changes in the lymphatic system and provoke an abnormal expansion of any part of the body, causing pain, disfiguring and making normal human life impossible.
Filariasis - what is it? How can I alleviate the condition with this disease and prevent its occurrence? We will try to answer these questions in this article.
How does filariasis occur
Lymphatic filariasis is known in the world as elephantiasis. It is provoked by parasites - filaria, transmitted through blood-sucking insects (mosquitoes, ticks, mosquitoes, horseflies, etc.).
Insects, in turn, are the transmission link between a sick vertebrate and a healthy person. Together with infected blood, microfilariae - living larvae, which then migrate through the wall of the stomach to the muscles of the insect, enter the bloodsucking stomach, where they become invasive larvae. At this stage of development, they already penetrate the oral cavity of their temporary owner and, during the next bite, break through its proboscis, appearing on the skin of a person.
Through small wounds or fissures, they enter the blood vessels and, after the last molt, become sexually mature helminths. This is how filariasis develops (you can see a photo of those suffering from this disease in the article). By the way, filarians live up to 17 years.
What causes the development of the disease
Interestingly, both microfilariae and adults do not cause much harm to the human body, but their death triggers an immunoallergic reaction of the host. By the way, if the body has few described helminths, from which a few sexually mature worms have developed, then an infected person may not feel that he is overtaken by filariasis. Symptoms of the disease in such cases do not appear.
In extreme cases, a carrier of helminths can, after many years after a trip to the tropics, when these parasites have already died, develop some kind of disease that has an erased clinical picture.
And the inhabitants of tropical countries, which are constantly bitten by bloodsucking insects, over the years become masters of a huge number of parasites. Their children, born from sick mothers, remain tolerant of infection for a long time, but over time, when "uninvited guests" begin to die in large numbers, the immune system responds to decaying helminth bodies with increasing force. Lymphatic vessels become inflamed, their walls thicken, growths appear on them, which interfere with the normal progress of the lymph, causing its stagnation and huge swelling.
Filariasis: symptoms of the disease at different stages
Lymphatic filariasis can be asymptomatic, acute, and chronic. And most often, the disease proceeds unnoticed by the patient, without manifesting itself. The incubation period can last from 4 months to 2 years. But even at this time, parasites are injured by the lymph nodes and blood vessels, and their metabolic products gradually poison the body of the infected person.
- In the first stage of a disease called filariasis, the symptoms are manifested by fever, as well as an allergic reaction, most often in the form of a rash on the hands. Increases in lymph nodes are observed (they change their shape and become painful), mastitis and bronchopneumonia occur.
- In the second stage of the disease (it occurs between 2 and 7 years from the onset of infection), the patient develops varicose veins and inflammation of the lymphatic vessels. Sometimes their tears are observed, accompanied by the appearance of signs of chyluria (milky color and gelatinous consistency of urine), chylous ascites (lymph fluid accumulates in the abdominal cavity ) and chylocele (the appearance of a tumor containing lymph).
- At the third (obstructive) stage of the disease, elephantiasis of the lower limb, and sometimes the genitals, develops.
Urinary filariasis
Blockage of the lymphatic ducts leads to the formation of lymphodema (reversible swelling of the soft tissues), which most often affects the legs, but in some cases, as already mentioned, the genitourinary system. At the same time, the patient fever periodically; he feels weakness and malaise. Such conditions are regular and last up to 15 days.
In men, the inflammatory process develops in the spermatic cords and testicles, which is expressed by painful sensations. Due to the expansion of the lymphatic vessels in the kidneys and urinary bladder, lymph begins to flow into the urine, staining it with a milky white color.
In parallel with the mentioned processes, compensatory (roundabout) paths for the outflow of lymph develop, and the edema passes. But if the disease is not treated, and more and more parasites continue to enter the body, then the condition goes into an irreversible stage (elephantiasis), in which even the complete destruction of all parasites does not eliminate elephantiasis.
Symptoms of filariasis appear in people without microfilariae in the blood
Since visitors do not have immunity, which has been forming among local residents since childhood, their disease begins to progress much faster. Both lymphodema (reversible soft tissue edema) and elephantiasis in those who visit the tropics can develop within 6-12 months.
By the way, microfilariae are no longer detected in the blood of such patients, since filariasis shows its symptoms only as an immune response, which means that the more pronounced they are, the less parasites in the blood.
How to diagnose filariasis
Since elephantiasis is a disease mainly of residents of the tropics, in Russia, doctors rarely have to deal with the full picture of this pathology, expressed in severe lesions of the lymphatic apparatus, organs of vision, skin, and the genitourinary system. And it is rather difficult to differentiate the early stage of the disease, since the intensity of its manifestations is too small.
And yet, how do doctors determine that a person has filariasis? Diagnostics in developed countries includes a 10-minute rapid test that identifies vuchereria (it is currently referred to the gold diagnostic standard). But in our country, alas, such studies are very difficult.
Filariasis Treatment
It should be noted right away that elephantiasis is not easy to treat. Even if all parasites are eliminated, irreversible changes remain in the body.
With the genital form of the disease, a significant improvement is observed after special operations. And to return to the legs the previous form is very problematic. Patients receive some relief after courses of massage that activate lymph flow, or when wearing compression tights.
With a diagnosis of filariasis, treatment is carried out using diethylcarbamazine preparations (Ditrazin, Banocid, etc.), which cause the death of parasites. They are taken for a week or 10 days, but these drugs can cause a severe allergic reaction, which makes their use difficult.
The mass death of helminths also leads to a worsening of the patient’s condition, therefore treatment is carried out according to a special scheme: they combine the use of these drugs with steroids, other antiparasitic drugs, as well as with the antibiotic Doxycycline, which gives a good effect.
Filariasis Prevention
If you find yourself in the tropics, the main thing is to avoid the bite of blood-sucking insects both indoors and outdoors. In the room they get rid of them with the help of fumigators, bed and window networks and air conditioners. Going out into the street, you need to wear clothes with long sleeves, and apply repellent to unprotected parts of the body.
In foci with a high prevalence of the disease, doctors recommend taking diethylcarbamazine preparations at a rate of 10 mg per kilogram of a person’s weight for 2 days every month.
Thanks to these measures, you will not be threatened with filariasis. Symptoms, photos of patients and other unpleasant moments that were provided in this article will not be able to poison you with memories of a trip to the tropics. Be healthy!