Loa loa filariasis

Loa loa filariasis is a parasitic disease caused by the Loa loa worm, a type of filarial nematode. It is transmitted to humans through the bite of an infected deer fly or mango fly belonging to the genus Chrysops. The disease is endemic in certain regions of West Africa and Central Africa.

Signs and symptoms

The primary symptoms of Loa loa filariasis include Calabar swelling, which are localized, non-painful swellings that appear on the arms and legs. These swellings are often accompanied by itching and joint pain. In some cases, the adult worms can be seen migrating under the skin or across the conjunctiva of the eye, causing significant discomfort.

Complications

If left untreated, Loa loa filariasis can lead to severe complications such as encephalitis and kidney damage. The presence of the worms in the body can trigger an immune response that may result in these serious conditions.

Transmission

The disease is transmitted through the bite of an infected deer fly or mango fly. These flies are most active during the day and are commonly found in the rainforests of West Africa and Central Africa. When the fly bites a human, it deposits larvae that mature into adult worms within the host.

Diagnosis

Diagnosis of Loa loa filariasis is typically made through a blood smear test, which can detect the presence of microfilariae in the blood. Serology tests may also be used to identify antibodies against the Loa loa worm.

Differential diagnosis

Loa loa filariasis must be differentiated from other filarial diseases such as onchocerciasis and lymphatic filariasis. These conditions have similar symptoms but are caused by different species of worms.

Prevention

Preventive measures include avoiding insect bites by using insect repellent, wearing long sleeves and pants, and using bed nets. Prophylactic medication such as diethylcarbamazine can also be taken by individuals living in or traveling to endemic areas.

Treatment

The primary treatment for Loa loa filariasis is diethylcarbamazine, which is effective in killing both the adult worms and the microfilariae. Ivermectin may also be used, although it is primarily effective against the microfilariae.

See also

• Onchocerciasis
• Lymphatic filariasis
• Parasitic disease
• Infectious disease