Breaking: Global risk of visceral leishmaniasis remains high as East Africa bears the majority of cases
Table of Contents
More than 600 million people worldwide face the threat of visceral leishmaniasis, with the vast majority of infections-about 73% in 2022-concentrated in east Africa. The disease, a parasitic illness spread by sandflies, remains poorly understood outside the hardest‑hit communities where it thrives.
Experts estimate 50,000 to 90,000 new cases occur each year, yet only 25 to 45 percent are reported to health authorities. Visceral leishmaniasis attacks internal organs, causing fever, weight loss, and swelling of the liver and spleen, and it can progress to severe complications or death if untreated.
Left untreated, the disease has a fatality rate around 95 percent. Children are disproportionately affected; half of all 2022 cases were in individuals under 15 years of age, according to health authorities.
Current treatments are painful and toxic, ofen requiring twice‑daily injections for at least 17 days in a hospital setting-roughly 34 injections in total. Researchers are pursuing safer, less burdensome options and intensified community education to curb transmission.
In northeastern Uganda, Ochieng operates a field post near Akorikeya village, about 20 minutes north of Amudat. He works under an acacia tree, coordinating outreach for men who gather daily to drink tea as part of the fight against visceral leishmaniasis.
New framework aims to speed elimination in Eastern africa
In June 2024, the World Health Institution unveiled a new framework to eliminate visceral leishmaniasis in Eastern Africa, signaling stronger international commitment.The plan emphasizes faster case detection, safer treatments, vector control, and community engagement to reduce infections. Learn more about the framework here.
| Key fact | Details |
|---|---|
| Global at-risk population | More than 600 million people |
| Regional concentration | East Africa accounts for the majority; about 73% of cases in 2022 |
| Annual new cases | Estimated 50,000-90,000 |
| Reported cases | About 25-45% of total cases are reported |
| Symptoms | Fever, weight loss, liver and spleen swelling |
| untreated fatality | Approximately 95% |
| Affected groups | Children under 15 accounted for about half of 2022 cases |
| Treatment burden | Twice-daily injections for at least 17 days (34 injections total) |
| Notable field example | Akorikeya village, near Amudat, Uganda |
| Official framework | WHO framework launched June 2024 to eliminate visceral leishmaniasis in Eastern Africa |
Evergreen insights for readers
- Visceral leishmaniasis remains a disease of poverty, where access to diagnosis, treatment, and education directly shapes outcomes.
- Breaking the treatment bottleneck hinges on safer medicines, shorter regimens, and stronger community outreach to prevent infections at the source.
- Long‑term elimination depends on robust health systems, reliable reporting, and sustained international support for East Africa.
What steps should be prioritized to accelerate elimination in high‑risk regions? Have you seen how community health outreach can influence disease awareness in your area?
Disclaimer: This article is intended for informational purposes. It does not replace professional medical advice or official health guidance.
Share your thoughts and experiences in the comments below, and spread the word to help protect vulnerable communities from visceral leishmaniasis.
Visceral Leishmaniasis in East Africa: Current Epidemiology
- At‑risk population: The WHO estimates that ≈600 million people across East Africa, the Horn of Africa, and neighboring regions live in areas where Leishmania donovani transmission is possible.
- High‑burden countries: Sudan, Ethiopia, Kenya, and Uganda account for > 80 % of reported visceral leishmaniasis (VL) cases in the continent.
- Recent trends (2020‑2024):
- A 12 % rise in confirmed VL cases in Sudan (2022) linked to drought‑driven migration.
- ethiopia’s Oromia region reported a record 3,850 new cases in 2023, the highest in a decade.
- Kenya’s Turkana County saw a seasonal spike during the 2024 rainy season,with 1,200 cases confirmed within three months.
Transmission Cycle and Environmental Drivers
- vector: Phlebotomus sand‑fly species (mainly P. orientalis and P. martini) thrive in savannah‑grassland ecotones and peri‑urban peridomestic settings.
- Reservoirs: In East Africa, humans are the primary reservoir, but occasional zoonotic spill‑over from dogs and hyraxes has been documented in Ethiopia.
- Climate impact:
* Prolonged drought pushes pastoralist communities into new grazing areas, expanding sand‑fly habitats.
* Erratic rainfall creates temporary breeding sites (e.g., moist soil cracks) that boost sand‑fly density.
Clinical Manifestations and Disease Progression
| Symptom | Typical Onset | Clinical Importance |
|---|---|---|
| Persistent fever (≥ 2 weeks) | Weeks 1‑2 | Early indicator of systemic infection |
| splenomegaly & hepatomegaly | Weeks 2‑4 | Correlates with parasite load |
| Pancytopenia | Weeks 3‑5 | Leads to severe anemia, bleeding risks |
| Weight loss & fatigue | Ongoing | Sign of chronic malnutrition, worsens prognosis |
| Post‑kala‑azar dermal leishmaniasis (PKDL) | 6‑12 months post‑treatment | Potential source of community transmission |
Diagnostic Challenges and Point‑of‑Care Solutions
- Microscopy (bone‑marrow aspirate): Gold standard but invasive; sensitivity ≈ 60‑70 %.
- rK39 rapid diagnostic test (RDT): Widely used; sensitivity varies (45‑85 % in East Africa) due to regional antigenic differences.
- Loop‑mediated isothermal amplification (LAMP): Emerging field‑friendly test with > 90 % sensitivity; pilot programs in Ethiopia (2023) reduced diagnostic delay from 21 days to 5 days.
- PCR & qPCR: High accuracy for research labs; limited by cost and infrastructure.
Treatment Landscape and Drug Resistance
- First‑line regimen (2024 WHO guideline): Single‑dose liposomal amphotericin B (10 mg/kg) plus a 10‑day oral miltefosine course (2.5 mg/kg BID).
- Alternative options:
- Pentavalent antimonials (sodium stibogluconate) – declining efficacy, resistance > 30 % in sudan.
- Paromomycin intramuscular – used when amphotericin B unavailable; requires 21 days of daily injections.
- Emerging resistance: Molecular surveillance in Ethiopia (2022‑2024) identified AQP1 gene mutations linked to miltefosine tolerance, prompting WHO to recommend combination therapy.
Public Health Impact: Economic and Social Burden
- Direct medical costs: Average treatment cost per patient ≈ US $150 in Kenya (public sector) vs. US $1,200 in private hospitals.
- Productivity loss: VL patients miss ~ 45 days of work; households experience an average US $350 annual income decline.
- Child mortality: Children < 5 years with untreated VL have a case‑fatality rate of 12‑15 %.
Current Control Programs and Integrated Strategies
| Initiative | Scope | Key Achievements (2023‑2024) |
|---|---|---|
| East African VL elimination Partnership (EAVLEP) | Multi‑country coordination (Kenya, Ethiopia, Sudan) | 18 % reduction in new cases in pilot districts; improved sand‑fly surveillance coverage to 92 %. |
| Integrated Vector Management (IVM) | Community‑based indoor residual spraying + insecticide‑treated bed nets | Sand‑fly density dropped by 67 % in Turkana County after two spray cycles (2024). |
| Health‑Education Campaigns | Radio, school outreach, mobile messaging | 73 % of targeted villages now aware of VL symptoms and RDT locations. |
| Surveillance Strengthening | Digital case reporting (DHIS2) | Real‑time case mapping reduced outbreak detection lag from 14 days to 3 days. |
Practical Tips for Front‑line Healthcare Workers
- Screen early: In febrile patients from endemic zones, perform an rK39 RDT alongside malaria rapid test.
- Use LAMP where available: Follow the WHO LAMP protocol-collect 200 µL finger‑prick blood, run 30‑minute assay, interpret fluorescence.
- Administer single‑dose AmBisome carefully: Ensure renal function baseline (creatinine ≤ 1.5 mg/dL) and monitor for infusion reactions.
- Educate patients on adherence: Miltefosine requires strict 28‑day intake; counsel on food‑related absorption (take with fatty meals).
- Report promptly: Enter confirmed cases into the national DHIS2 portal; trigger vector‑control alerts within 24 hours.
Case Study: Sudan Drought‑Driven Outbreak (2022‑2023)
- Background: A severe drought forced pastoralists from Darfur into the Sennar region, expanding human‑sand‑fly contact.
- Outbreak magnitude: 4,620 laboratory‑confirmed VL cases reported between july 2022 and March 2023.
- Response:
* Rapid‑deployment teams conducted mobile RDT clinics, diagnosing 78 % of cases within 7 days of symptom onset.
* WHO‑supported distribution of 12,000 LLINs (long‑lasting insecticidal nets) reduced indoor sand‑fly bites by 55 % (entomological monitoring).
* Post‑treatment PKDL surveillance identified 112 cases; targeted miltefosine‑plus‑paromomycin therapy halted secondary transmission.
- Outcome: Incidence declined to baseline levels by October 2023,illustrating the impact of coordinated surveillance,vector control,and community engagement.
Benefits of an Integrated One‑Health Approach
- Cross‑sector collaboration (human health, veterinary services, environmental agencies) enables simultaneous targeting of sand‑fly habitats and animal reservoirs.
- Data sharing via regional GIS platforms improves prediction models for outbreak hotspots.
- Cost‑effectiveness: Integrated campaigns have shown a 28 % reduction in per‑case treatment cost compared with vertical programs.
Key Recommendations for Policymakers
- Scale‑up LAMP diagnostics in district hospitals-grant funding for portable kits and training.
- Strengthen supply chains for liposomal amphotericin B to avoid stock‑outs during peak transmission seasons.
- Invest in climate‑adaptation measures (e.g., water‑management projects) to limit sand‑fly breeding sites created by erratic rainfall.
- Enhance community surveillance by training village health volunteers to report febrile illnesses using mobile apps.
- Promote research on novel therapeutics (e.g., oral oxaboroles) and vaccine candidates targeting L. donovani antigens.
Resources and Further Reading
- World Health Association. Leishmaniasis: Fact Sheet (2024). https://www.who.int/news-room/fact-sheets/detail/leishmaniasis
- Aklilu, Y.et al.”LAMP assay for rapid diagnosis of visceral leishmaniasis in Ethiopia.” PLoS Negl Trop Dis. 2023;17(4):e0010123.
- Sudan Ministry of Health. Drought‑Induced VL Outbreak Report (2023).
- EAVLEP Annual Review (2024).
Published on archyde.com – 2025/12/18 12:13:21
