A disease transmitted by the sand fly, kala azar has killed in the past few decades many hundreds in Bihar, the state worst hit by it. Over 70 people died last year.

Since 1988, MSF has treated more than 100,000 kala azar patients in Sudan, Ethiopia, Kenya, Somalia, Uganda and Bangladesh besides India. Its doctors provide liposomal amphotericin B, a safe and effective drug.

MSF says that it has treated more than 10,000 patients with an initial cure rate of over 98 percent in the last five years in Vaishali as well as neighbouring districts.

All treatment is free of cost, says MSF project coordinator Delphine Altwegg. It says it cured around 2,000 patients each year in the last five years.

Winner of the Nobel Peace Prize in 1999, MSF has set up a treatment centre in Hajipur Sadar Hospital and in the primary health centres of Vaishali.

"MSF has been providing the best medical services to kala azar patients," Altwegg said.

Jonathan Jennings, country director of MSF in India, said MSF teamed up with the Bihar government this year to launch a campaign to eradicate the disease.

MSF says it has proved that it is possible to diagnose and treat the patients with a high cure rate even in remote settings.

According to C.P. Thakur, a former central minister and chairman of the Kala Azar Task Force, the disease, a recurring epidemic, affects thousands in Bihar each year.

Over 23,000 cases were reported in 31 of Bihar's 38 districts in 2011.

Over 750 people died of kala azar in the past five years. Authorities in Bihar have vowed to stamp it out by 2015.

Kala azar, medically called visceral leishmaniasis, is known as the poor man's disease because it affects the poorest.

The sand fly, which transmits the disease, multiplies in the cow dung that villagers use to plaster their shanties or as cakes for fuel.

The flies survive on the sap in banana and bamboo groves and on decomposed cow dung heaps.

The disease is characterised by fever, weight loss, swelling of the spleen and liver and can lead to cardiovascular complications, resulting in death.

Experts say poor living standards and unhygienic conditions make members of the Mushahar community, who are Dalits, easy prey.

Around 90 percent of the world's kala azar cases are found in India, Bangladesh, Nepal and Sudan.