"The vaccine formulation is highly potent. We have shown the way and further research will give us a weapon against kala azar," Nahid Ali, scientist at the Infectious Diseases and Immunology Division of the IICB here, told IANS.

Transmitted by the sandfly, it is a slow progressing indigenous disease that leads to infection in the liver and spleen and their enlargement.

Termed by the World Health Organisation as a neglected disease, kala azar, or leishmaniasis as it is known in medical jargon, puts an estimated 165.4 million people at risk in the states of Bihar, Jharkhand, Uttar Pradesh and West Bengal.

Provisional figures by the union health ministry show that kala azar claimed 20 lives and afflicted 14,227 people till July this year.

"Despite numerous efforts, there is still no licensed vaccine against kala azar," Ali told IANS.

IICB functions under the Council of Scientific and Industrial Research (CSIR).

Now, there is some hope.

To create a vaccine against kala azar, the scientists used what is called the antigen-adjuvant approach.

Generally, an antigen, when introduced into the body, makes it produce antibodies against the substance to deactivate it.

In the case of the kala azar parasite, which resides inside the host cell, the antigen used triggers certain immune cells to fight the parasite.

The adjuvant boosted the body's immune response to the vaccine.

"It (kala azar) is a poor man's disease and drugs are quite expensive. Vaccine formulations will be a big help in the fight against the disease," Pradeep Das, director of the Rajendra Memorial Research Institute of Medical Sciences (RMRIMS) in Patna, told IANS.

RMRIMS is mandated by the Indian Council of Medical Research to provide scientific understanding and technology needed to support the fight against kala azar.

The IICB findings have been published in the Journal of Molecular Pharmaceutics.