A recent epidemic of elephantiasis was reported in the Kamwenge District of western Uganda. Pictured, asymmetrical lymphedema (lower limb swelling) typical of the disease. An investigation by the country's Ministry of Health highlighted the root cause to be volcanic soil.
Christine Kihembo
Certain parts of eastern and central Africa have soil from volcanic rocks formed more than 2.5 million years ago, and irritant minerals can cause itching, pain and eventual swelling and scarring after prolonged exposure.
Christine Kihembo
This method of contracting the disease, through volcanic soil, is known as podoconiosis, or non-filarial elephantiasis. Pictured, an early manifestation of podoconiosis, involving mild lymphedema (swelling) with a few warty growths on the feet.
Christine Kihembo
The majority of cases are caused by the parasitic worm Wuchereria bancrofti -- responsible for 90% of cases -- and is called lymphatic filariasis.
Courtesy Mae Melvin/CDC
Lymphatic filariasis is transmitted by different types of mosquitoes including Culex, Aedes and Anopheles mosquitoes. The young larval forms are picked up when mosquitoes feed on human blood. Once inside the mosquito, the parasites migrate to the gut of the insect, where they develop and move to the head of the mosquito, ready to penetrate human skin when the insect next feeds on a human.
CDC
The swelling of body parts is caused by adult forms of parasitic filarial worms, which form nests in the lymph vessels and lymph nodes. India has the greatest burden of lymphatic filariasis in the world, and a national campaign was launched in December 2014 to deliver 400 million medication tablets to communities at risk of infection.
Courtesy Sabin Institute
The main strategy to control lymphatic filariasis is the widespread distribution of the deworming drugs diethylcarbamazine and albendazole, to prevent infected people from transmitting the disease. Podoconiosis has no treatment.
Courtesy Sabin Institute
The only option once patients have the severe swelling characteristic of elephantiasis is to manage symptoms by draining fluid where possible or else to keep limbs and wounds clean.