Going the last mile to eliminate a long-neglected disease

January 28, 2022 by Isha Jain and Bhoomika Srivastava

Every year, 90,000 people are affected by visceral leishmaniasis, a deadly parasitic disease. PATH and partners are making great strides toward elimination.

Vector control is the backbone of the kala azar elimination strategy. PATH’s Amresh Kumar, MD, and other team members in Uttar Pradesh conducting indoor residual spraying that helps reduce the vector, the sandfly. Photo: PATH.

PATH’s Amresh Kumar, MD, and other team members in Uttar Pradesh conduct indoor residual spraying to help control the vector, the sandfly. Photo: PATH.

Around the world, neglected tropical diseases (NTDs) affect more than a billion people in sub-Saharan Africa, Asia, and Central and South America. The 20 conditions in this group are often linked to specific environmental conditions, such as tropical and subtropical climates, and are most common in the poorest communities.

Visceral leishmaniasis, commonly known as kala azar, is an NTD and the second most deadly parasitic disease in the world. There are around 50,000 to 90,000 new cases worldwide each year, most of which occur in Brazil, India, and South Africa.

Like many other NTDs, visceral leishmaniasis is prevalent in rural areas where access to adequate sanitation, clean water, and adequate housing is limited. Other major risk factors include poverty, malnutrition, population mobility, and climate vulnerability.

The disease affects the internal organs, causing symptoms such as fever, weight loss, and anemia. When left untreated, it is fatal in more than 95 percent of cases. Additionally, around 5 to 10 percent of patients go on to develop post-kala-azar dermal leishmaniasis, a condition that makes the existing infection potentially transmissible to others.

Since 2018, PATH has supported the government of India’s efforts to eliminate visceral leishmaniasis in Uttar Pradesh, where the disease is prevalent in 14 of 75 districts.

Partnering to eliminate the deadly disease

The government’s kala azar elimination program leverages two key strategies: early diagnosis and complete treatment, and vector control.

Early diagnosis and complete treatment require active case detection in the community—one of the most challenging parts of kala azar elimination.

In 2018, the government of Uttar Pradesh partnered with the United Nations Children’s Fund to launch DASTAK—which means “a knock on the door” in Hindi—an active case detection campaign. PATH has been providing end-to-end support to DASTAK since its launch.

Through DASTAK, PATH trained Accredited Social Health Activists (ASHAs)—women health care providers who work in villages and small towns—on kala azar elimination. ASHAs visit every household to identify active cases. They look for skin lesions or fever that has lasted for more than two weeks—signs of a suspected case.

In December 2021, ASHAs visited more than 23,000 houses in 70 villages across Ballia, Deoria, Ghazipur, and Kushinagar—four districts of Uttar Pradesh. From these visits, they identified 182 suspected cases, three of which tested positive for visceral leishmaniasis and five for post-kala-azar dermal leishmaniasis.

Through ASHA engagement, 100 percent of the suspected cases are tested for visceral leishmaniasis. PATH helps expedite the process of bringing these cases to public health centers for testing, and facilitates treatment for those found positive. Treatment starts within two days following any positive test.

Indoor residual spraying (IRS) is the key strategy for vector control. Leishmania parasites, which cause visceral leishmaniasis, are transmitted through the bite of infected sandflies. Using insecticidal spray, IRS is a proven approach to interrupting transmission of the parasites. PATH supports IRS microplanning, coordinating with the government to conduct IRS twice a year, targeting high-transmission seasons before and after monsoon rains.

PATH also provides support for community sensitization—which includes increasing awareness and education about the disease and the elimination strategies, as well as case management—to ensure those infected receive care.

Promising results and ongoing action

Thanks to the DASTAK campaign, active case surveillance, appropriate case management, and early treatment for visceral leishmaniasis patients have increased significantly, leading to improved health conditions and a lower fatality rate.

Visceral leishmaniasis (VL) cases dropped from 120 in 2018 to 49 in 2021. Post-kala-azar dermal leishmaniasis (PKDL) cases dropped from 72 in 2018 to 51 in 2021.

Though there has been considerable progress, PATH’s work will continue until the disease is eliminated. PATH is monitoring progress and analyzing learnings to continue iterating and improving the program ahead of some key challenges.

For instance, acute shortage of spray pumps for IRS is making it difficult to maintain IRS programs for vector control.

Furthermore, the COVID-19 pandemic posed its own set of unique challenges. National lockdown policies meant many meetings and health care worker trainings were postponed or canceled.

Amresh Kumar, MD, Deputy Director of Neglected Tropical Diseases at PATH India, says, “Even amidst these challenges, we continue to support the government in its efforts to eliminate visceral leishmaniasis and other NTDs.”