The title of this article was awarded an Honourable Mention via Global Health NOW’s ‘Untold Stories in Global Health’ competition. It is also available on their blog, here.
It is unsurprising that neglected tropical diseases get the fewest column inches and remain unknown to vast swathes of the general population. But if you were asked what the largest parasitic killer was, after malaria, would you correctly answer Kala-Azar?
Also going by the names of Leishmaniasis and black fever, this isn’t a disease of the European or Northern Hemisphere masses, despite long causing significant fatality figures and appearing on many NGOs agendas—including Médecins Sans Frontières (MSF), which reports treating more than 100,000 people with the disease since 1988.
Endemic in almost 50 countries and with an estimated 200 million at risk, there are an estimated 201,500 – 378,500 cases a year, according to Lepra (an active NGO working in this field). The unseen Leishmania parasite is transmitted by the bite of the equally insidious yet unprepossessing female phlebotomine sandflies. Tropical areas, especially during the autumn harvesting season, prove particularly hospitable to this vector.
Kala-Azar progresses from skin ulcers at the site of infection to the more aggressive form of visceral Leishmaniasis, effectively destroying the immune system. Left untreated, it almost always causes death through complications of any combination of anaemia, weight loss and vital organ failure, notably swelling of the liver and spleen.
It is also associated with poverty: Lepra identifies it as “the poor man’s disease.” For example, sandflies frequently occupy cracks of houses made from mud commonly inhabited by the poor. The disabling aspect of the disease prevents sufferers from being economically self-sufficient while the burden of treatment costs can push their families further towards extreme poverty.
Unfortunately, being identified with and treated for Kala-Azar is fraught with its own dangers. The most effective diagnostic tools are invasive, requiring extraction of either bone marrow or splenic aspirate to visualize amastigotes (an intracellular form without visible external cilia or flagella typifying the leishmanial stage). Invariably, this diagnostic gold standard is unavailable in endemic areas, but serological testing is a common and generally reliable alternative, according to the WHO.
What is life actually like for someone with Kala-Azar? Lepra’s work in Bihar, India offers a telling insight. Consider 8-year old Ruby Kamari, who was originally misdiagnosed with malaria. Only after a series of referrals and 2 rounds of treatment—which proved financially devastating for her family—is she able to eat a little more than half a chapati (flatbread) a day, sleep in more regular cycles and see the melon-sized ballooning of her abdomen lessen.
Another case echoes this debilitating lack of knowledge across the general population: Devi, the father of a 7-year old son who is 2 months into treatment for Kala-Azar remarked, “We thought it was just a simple fever. We live in a hut, we don’t have the knowledge. If a mobile testing facility and treatment facility came to us, it would make life easier.”
Speaking at the London-based Medsin (UCL) conference in 2015, MSF clinician Ana Garcia Mingo shared her experiences working within conflict areas to curb the spread of Kala Azar. She underscored that after any crisis, preventative care is the first thing that stops, but this is also a truism of this disease across the regions it targets.
While there are no prophylactic drugs nor vaccine for the disease, preventative recommendations as per other insect-borne diseases extend to limiting time spent outdoors, particularly from dusk until dawn when sandflies are most active, and application of insect repellent. Indoors, at-risk populations are advised to apply pyrethroid-containing insecticide to furnishings and to make use of bednets.
Although entirely treatable, inexpensive yet effective chemotherapy is lacking in many endemic areas, not least Sudan, according to a 2008 study published in Transactions of the Royal Society of Tropical Medicine & Hygiene. Although the overwhelming portion of those who receive treatment reportedly recover and are highly unlikely to contract the disease again, access to treatment and both donor and health system awareness of the disease is varied but still, devastatingly, the disease occupies a discourse of the ‘neglected.’
Image Credit: Ruby and her family look out from beneath their bednet. Peter Canton via Lepra.