mansonellosis

Mansonellosis is a human parasitic infection caused by filarial nematodes of the genus Mansonella. The species most commonly associated with human disease are Mansonella perstans, Mansonella ozzardi, and Mansonella streptocerca. The disease is considered a neglected tropical disease and occurs in tropical regions of sub-Saharan Africa, parts of the Caribbean, and areas of Central and South America, with transmission by biting insects such as midges (Culicoides) or blackflies (Simulium), depending on the species and locale.

Clinical features are often mild or absent. When symptoms occur, they are nonspecific and may include pruritus, urticaria, episodic fever, arthralgia or myalgia, abdominal discomfort, and mild edema. Microfilariae are usually present at low levels and may be detectable in peripheral blood (for some species) or in skin snips (for others); subclinical infections are common.

Diagnosis is based on identification of microfilariae in blood, skin snips, or tissue, guided by geographic exposure and morphological features; molecular methods (PCR) can aid species confirmation. Serological tests have limited utility due to cross-reactivity and regional variability.

Treatment regimens vary and no universal regimen exists. Ivermectin is commonly used to reduce microfilarial loads; albendazole is sometimes given; doxycycline has been investigated because of its activity against Wolbachia endosymbionts in some Mansonella species. DEC is generally not uniformly effective against Mansonella and may be avoided in certain settings. Management focuses on symptom relief and reduction of microfilaremia in affected individuals, with public health emphasis on vector control and surveillance in endemic areas.

The genus Mansonella is named after Sir Patrick Manson, a pioneer of tropical medicine.