Kala Azar in India: Treading the last mile towards elimination

Kala azar (visceral leishmaniasis), also called black fever, is on the cusp of elimination in India, with a decline in cases from 77102 in 1992 to 9241 in 2014, 524 cases in 2023 and finally, to only 429 cases in 2025 according to the latest available data. 

A country must maintain under one case per 10,000 population for three consecutive years to receive the World Health Organization’s elimination certification and India has maintained the levels for two consecutive years now.  Here’s why India’s near-success story matters.

Understanding Kala Azar

Kala Azar is a neglected tropical disease that is caused by protozoan parasites transmitted through sandfly bites.  

The disease affects the internal organs, causing symptoms such as fever, weight loss, and anaemia. If left untreated, it can be fatal. A major complication of the condition is post Kala Azar dermal leishmaniasis (PKDL), PKDL appears as a rash on the face or other areas of the skin; it presents as hypopigmented patches or small nodules, and acts as a major reservoir for transmission. Transmission occurs when the sand fly bites an infected person or animal, then bites someone else, injecting them with the parasite leishmania. 

Kala Azar is curable with medication when given at the right time. Injectable anti-parasitic drugs are the first line of treatment. Oral miltefosine is also used to treat both Kala Azar and post-Kala Azar dermal leishmaniasis.

​Also Read: Celebration and vigil: On India, kala-azar and trachoma

Efforts in India

Efforts to eliminate Kala Azar in India have seen highs and lows. Explaining the trajectory of India’s story, Nirmal Kumar Ganguly, former director general, Indian Council of Medical Research (ICMR), says that the current stage India is close to elimination, and is a “great achievement” since 70% of Kala Azar cases in the world were in the Indian subcontinent.

Drug development and ensuring access to drugs played a major part. Resistance to the Sodium Stibogluconate (SSG) injection, which was earlier the only drug to treat the condition, led to multiple outbreaks and fatalities. Oral miltefosine, he notes, provided a safe oral drug for the first time, with a 20-day treatment regime, says Prof Ganguly. The other major effort came through liposomal amphotericin B (AmBisome), an injectable drug with a high cure rate that can now be taken as a single shot, and which was obtained free for India, through WHO negotiations, from pharma major Gilead Sciences.

Sanjay Sarin, Asia Continental Lead and Director, South Asia, Drugs for Neglected Diseases Initiative (DNDi), echoed this view: the single-dose treatment replacing three earlier regimens that were long, toxic and painful making it difficult for patients to complete treatment. The new treatment significantly improved adherence and helped reduce tranmission.

Diagnostics have been a game-changer. Prof. Ganguly notes that a Loop-mediated Isothermal Amplification (LAMP) assay, a sensitive molecular diagnostic tool that has been developed can detect cases early and will eliminate hazardous sternal puncture and splenic puncture tests to diagnoses the disease. The point-of-care RK 39 rapid diagnostic test also helped tip the scale.

Additionally, surveillance aided the battle: good surveillance in both endemic endemic and non-endemic regions and Neglected Tropical Disease programme funding and political prioritisation helped the country immensely, Prof Ganguly says. 

Challenges to elimination

Kala Azar is considered one of the most dangerous neglected tropical diseases, and its elimination is challenging. Why? Because unlike viral diseases that have successful vaccination programmes, there is no vaccine for Kala Azar as yet. Moreover, PKDL remains a significant challenge to sustaining elimination, as patients may feel otherwise healthy and not seek treatment. Undiagnosed PKDL can silently sustain transmission even when Kala Azar cases decline. Drug resistance is another problem as well co-infections with other diseases or double infections with two Leishmania species.

Compounding these hurdles is climate change: rising temperatures, humidity, migration, and changing land use that can increase vulnerability and expand sandfly habitats, explains Dr. Sarin. Prof. Ganguly adds that movement of populations from endemic to non-endemic areas and the parasite moving into new areas, adds to the challenges.

India’s story of hope

Active case detection, strengthened vector control, including indoor residual spraying, decentralised diagnosis and treatment, and robust surveillance are among the strategies that worked to help India progress toward elimination, alongside strong political commitment.

Dr. Sarin says that “continued vigilance will be required to sustain the gains achieved through Kala Azar elimination efforts. Investing in the development of new drugs and diagnostics is crucial. Innovative vector control and surveillance strategies, as well as the continued contribution of intersectoral ministries, are crucial to sustaining the elimination phase.”

Like many NTDS, visceral leishmaniasis is prevalent in rural areas and affects the poorest communities, causing prolonged illness, loss of income, and death if left untreated. Eliminating it, therefore, would not just be a public health milestone, but a major equity and development achievement.

For India, the goal is within reach, as is the promise of a brighter future for thousands.

(Nabeela Khan is a Delhi-based health and science journalist. nabeelainayati@gmail.com)

Published – January 31, 2026 12:43 pm IST