Posts Tagged ‘worm of the week’

Worm of the Week – Onchocerciasis

September 27th, 2010

Another installment from our Worm of the Week series, courtesy of student campaigners from Boston University! Today we feature:

Onchocerciasis
Onchocerca Volvulus

Onchocerciasis

Onchocerciasis is caused by the filarial worm Onchocerca volvulus.  Transmission is via the bites of infected blackflies of Simulium species, which carry immature larval forms of the parasite from human to human. In the human body, the larvae form nodules in the subcutaneous tissue, where they mature to adult worms. After mating, a female can lay up to 1000 microfilariae/day, which move through the body, and when they die they cause a variety of conditions, including blindness, skin rashes, lesions, intense itching and skin depigmentation. A total of 18 million people are infected with the disease and have dermal microfilariae, of whom 99% are in Africa.

» Read more: Worm of the Week — Onchocerciasis

Worm of the Week – Lymphatic Filariasis

August 24th, 2010

Another installment from our Worm of the Week series, courtesy of student campaigners from Boston University! Today we feature:

Lymphatic Filariasis


Wuchereria bancrofti AND Brugia malayi AND Brugia timori

Lymphatic Filariasis

A physically and socially debilitating disease, lymphatic filariasis affects over 120 million people in 80 different countries. The thread-like parasitic filarial worms, Wuchereria bancrofti (causing most infections worldwide), and Brugia malayi and Brugia timori (primarily in Asia) lodge in the human lymphatic system. There, adult worms mate and produce millions of microscopic microfilariae that circulate in the person’s blood. Infection spreads by mosquito bites containing larval worms that travel to lymph and grow into adults which takes about six months. Adult worms can live 5 to 7 years.

Symptoms

Sometimes called elephantiasis due to the engorgement and thickening of skin, lymphatic filariasis is characterized by lymphedema, or fluid collection due to improper functioning of the lymph system resulting in swelling. Most infected individuals are asymptomatic and will never develop symptoms. In the severest cases, fluid accumulates in the legs, arms, breasts, and genitalia. Infected persons are at increased risk for bacterial infections in the skin and lymph system.

Diagnosis

Microscopic identification of microfilariae in blood smear. Blood collection should be done at night.

Treatment

Diethylcarbamazine (DEC) kills microfilaria and some of the adult worms; Ivermectin kills microfilaria.

Prevention and Control

The best way to avoid lymphatic filariasis is to avoid mosquito bites (sleep under mosquito net, use repellent, wear long sleeves and trousers). In 1997, the World Health Assembly called for the global elimination of lymphatic filariasis as a public health problem. The strategy for elimination is based on treating everyone eligible to take the medicine living in an affected community with a dose of two drugs: albendazole is used in conjunction with ivermectin (sub-Saharan Africa) and with DEC (elsewhere in world).

Sources: http://www.cdc.gov/ncidod/dpd/parasites/lymphaticfilariasis/index.htm

http://www.cartercenter.org/health/lf/index.html

Just 50 cents campaign: http://www.globalnetwork.org/just50cents