Microfilaria

Microfilaria of Dirofilaria immitis (Heartworms) Surrounded by Neoplastic Lymphocytes 1

Microfilaria manaus br

Microfilaria are the larval stage of filarial worms, which are parasitic nematodes. These larvae are typically found in the blood or skin of the host and are transmitted to new hosts by blood-feeding arthropods, such as mosquitoes and blackflies. Microfilariae are an essential part of the life cycle of filarial worms, which cause various diseases in humans and animals.

Life Cycle

The life cycle of filarial worms involves several stages, starting from the adult worms residing in the host's body. The adult female worms release microfilariae into the host's bloodstream or skin. These microfilariae are then ingested by a vector, such as a mosquito, during a blood meal. Inside the vector, the microfilariae develop into infective larvae. When the vector bites another host, the infective larvae are transmitted and mature into adult worms, completing the cycle.

Diseases Caused

Microfilariae are responsible for several significant diseases, including:

• Lymphatic filariasis: Caused by Wuchereria bancrofti, Brugia malayi, and Brugia timori, leading to severe swelling and elephantiasis.
• Onchocerciasis: Also known as river blindness, caused by Onchocerca volvulus, leading to severe itching, skin changes, and blindness.
• Loiasis: Caused by Loa loa, leading to Calabar swellings and eye worm.

Diagnosis

The presence of microfilariae in the host can be diagnosed through various methods, including:

• Blood smear: A drop of blood is examined under a microscope to detect microfilariae.
• Skin snip: A small piece of skin is examined for the presence of microfilariae, particularly in cases of onchocerciasis.
• Serological tests: These tests detect antibodies or antigens related to filarial infections.

Treatment

Treatment of microfilarial infections typically involves the use of antiparasitic medications such as:

• Ivermectin: Effective against microfilariae and used in mass drug administration programs.
• Diethylcarbamazine (DEC): Used to treat lymphatic filariasis and loiasis.
• Albendazole: Often used in combination with other drugs to enhance efficacy.

Prevention

Preventing microfilarial infections involves controlling the vector population and protecting individuals from bites. Measures include:

• Using insect repellents and mosquito nets.
• Implementing vector control programs to reduce the population of mosquitoes and blackflies.
• Mass drug administration programs to reduce the prevalence of microfilariae in the human population.

Related Pages

• Filarial worm
• Lymphatic filariasis
• Onchocerciasis
• Loiasis
• Ivermectin
• Diethylcarbamazine
• Albendazole