Introduction:
Lymphatic filariasis is a parasitic disease caused by microscopic thread-like worms. In males, swollen scrotum, also known as hydrocele, is seen in patients suffering from lymphatic filariasis. This disease can cause permanent disability and is the primary cause of permanent disability all over the world.
What Is Lymphatic Filariasis?
It is defined as a disease of parasitic origin that is caused by microscopic thread-like worms. It spreads through a mosquito bite. Mosquito-borne filarial nematodes cause lymphatic filariasis. The mosquito-borne filarial nematodes like Wuchereria bancrofti, Brugia malayi, and Brugia timori are behind the infection of this disease. Most cases of lymphatic filariasis are caused by Wuchereria bancrofti. In the Asian continent, the disease is observed to be caused by Brugia malayi and Brugia timori. The lymphatic filariasis caused by Wuchereria bancrofti is also known as bancroftian filariasis. The human body's lymphatic system is primarily known for defending the body from any infection. These filarial worm species weaken the lymphatic system by attacking it. These filarial worm species are transmitted in the human body through mosquito bites. The adult worms of lymphatic filariasis live and propagate in the body's lymphatic system. These worms are stated to live upto 5 to 8 years, and during this period, they reproduce microfilariae. Microfilariae are immature larvae that get into circulation.
When a mosquito bites an infected host, it ingests the blood; this ingested blood has microfilariae, which mature into infective larvae. When the mosquito bites someone, these infective larvae are transplanted on the skin's surface, from where they easily enter the person's circulation. After entering the circulation, these larvae migrate to the lymphatic system, where they grow into adult worms. In this way, the cycle of transmission is continued. The type of mosquito varies from continent to continent; in Africa, the common vector for this disease is Anopheles; in the Americas, Culex quinquefasciatus is found to be the vector. In the Asian continent and the Pacific region, Aedes and Mansonia are present as vectors.
What Is the Significance of the Lymphatic System?
A lymphatic system is a collective group of ducts, vessels, and nodes. A clear white fluid primarily made by white blood corpuscles significantly lymphocytes known as lymph is circulated via the lymphatic system. The lymph provides immunity to the body, making the lymphatic system an integral part of the immune system. Lymphocytes are of two types: T cells and B cells. These cells provide the body with immunity by detecting and fighting any disease-causing microorganisms or foreign particles. Lymph vessels transfer lymph fluid via the lymph nodes all over the body. The lymph node not only transfers the lymphocytes but also produces them. The lymph nodes are found in a pack at various locations in the body, such as the neck area, armpits, and groin. As the infection is detected, lymph nodes produce more lymphatic immune cells. Lymphocytes produce antibodies.
What Are the Symptoms of Lymphatic Filariasis?
The person infected by lymphatic filariasis shows no symptoms generally. Most of the time, the person is unaware of being infected by it. In such patients, while pathological testing of blood, the pathologist may detect worms in the blood and can make the patient aware of it. The symptoms may occur years after the ingestion. In limited cases, the symptoms are seen; the classic symptoms were swelling on various body parts such as arms, legs, and thoracic area. When the skin of the leg gets thickened, and tissue hardens because the disease was not treated in time, this condition is called elephantiasis. In males, painful, swollen scrotum and penis can be seen. In females, breasts and genitals can be affected. The disease grows into a chronic condition; it causes lymphedema, skin thickening, and enlarged limbs. The swelling becomes severe, which can lead to the disfiguration of the organ. These chronic systems can lead the patient to low self-esteem or affect them emotionally.
How Is Lymphatic Filariasis Diagnosed?
A thick blood smear is observed under the microscope to check the presence of microfilariae. A blood smear should be taken from finger-prick blood. Blood must be collected during the day or night; generally, it is observed that the disease-causing microfilariae are found in circulation at night, which is termed nocturnal periodicity, but the periodicity of the microfilariae should be taken into consideration while taking the blood specimen for testing. Serological techniques and various routine assays can be alternatives to microscopic evaluation. The rapid diagnostic test known as the alere filariasis test strip (FTS) can be used. The DNA of the microfilariae can be detected in the bloodstream via polymerase chain reaction (PCR).
What Are the Neglected Tropical Diseases?
The diseases, which are found mostly in tropical environments, are caused by various toxins, viruses, bacteria, etc., and are neglected by the health industries are known as the neglected tropical diseases. These diseases also affect poor countries and areas where people cannot afford expensive treatments or medicines. Hence, it is observed that the research and production of medicines for these diseases are not carried out as no monetary profit is involved. These are the group of diseases that can be proven life-altering to the population. They have the potential to cause permanent disability and disfigurement and also reduce life expectancy. Lymphatic filariasis is one of the neglected tropical diseases (NTD).
Conclusion:
This disease has restrictive treatments and does not have more options for treating patients. Some steps are taken to control the mosquito population, named vector control. Preventive chemotherapy is also used in endemic populations to control the spread of lymphatic filariasis. It is stated that mass drug administration (MDA) can help eliminate larvae. Lymphatic filariasis is a vector-borne disease that can be dangerous as it is asymptomatic most of the time till it gets into a chronic stage. Lymphedema and elephantiasis can be debilitating. The patients can have chronic conditions like kidney failure or damage, swollen limbs, and swollen genitals. The physician can compose a treatment plan which may help manage the filariasis in time. When it is not treated in time, it may lead to several health complications.
