Abstract
Visceral leishmaniasis is transmitted by infected female sand flies. However, entomological data from refugee camps remained limited. This study aimed to describe sand fly fauna and assess natural Leishmania infection in selected refugee camps in Ethiopia. The study was conducted in four refugee camps. Sand flies were collected using a CDC light trap and sticky trap. Both male and female sand flies were dissected, and morphologically identified. The female sand flies were preserved in 95% ethyl alcohol for Leishmania DNA screening. A total of 2196 sand flies were collected. Phlebotomus rodhaini, the only Phlebotomus species identified, accounted for 1.7% of the collections. Sergentomyia antennatus was the most abundant species (50.8%), followed by S. africanus (15.8%), S. schwetzi (14.3%), S. bedfordi (10.9%), S. clydei (5.2%), S. squamipleuris (1.2%), and S. adleri (0.1%). Species richness was highest in Terkidi camp, whereas overall diversity was greatest in Sherkole. Indoor collections were limited (< 2.3%), confirming predominantly exophilic resting behavior. Termite hills and peridomestic habitats harbored the highest sand fly densities. Polymerase chain reaction screening showed no evidence of Leishmania infection. This first entomological survey conducted in refugee camps in Ethiopia documents a sand fly fauna dominated by outdoor collections, a very low abundance of Ph. rodhaini, and no detectable Leishmania infection. These findings suggest the need for longitudinal monitoring to capture seasonal variation.
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Data availability
The datasets generated and/or analyzed during the current study are available from the corresponding author upon reasonable request.
Abbreviations
- CDC LT:
Centers for Diseases control and prevention light trap
- CPD:
Compounds that contains households
- DNA:
Deoxyribonucleic acid
- MoH:
Ministry of health of Ethiopia
- NH:
Natural habitat
- PCR:
Polymerase chain reaction
- ST:
Sticky trap
- TH:
Termite hill
- VL:
Visceral Leishmaniasis
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Acknowledgements
We sincerely thank the FDRE Refugee and Returnee Service (RRS) for their support in facilitating communication with regional offices. Our appreciation also goes to the RRS coordination offices, camp coordinators, volunteers, and refugee community members for their kind cooperation during indoor and household compound sand fly collections, and to the community leaders for their generous help in organizing participants. We are especially grateful to Dr. Abebe Animut and Mr. Wossen Sisay for their thoughtful assistance in providing field supplies and ensuring smooth logistical arrangements before deployment.
Funding
This study was financially supported by grants from Addis Ababa University.
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HB, AA, GT, BE and EA conceived and designed the study. All authors were involved in proposal writing and participated in field coordination, data collection, supervision and overall implementation of the study. HB analyzed the data and drafted the manuscript. All authors read and approved the final manuscript.
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Consent was sought from each refugee camp coordinators including protection, security and health coordinators) and informed consent was also sought from head of households from where sand flies were collected in their compound and/or indoor. The study obtained ethical clearance from the Aklilu Lemma Institute of Health Research-Institutional Research Ethics Review Committee (ALIHR-IRERC) prior to data collection (Ref. No.: ALIPB IRERC/112/2015/23). A permission letter was obtained from Federal Democratic Republic of Ethiopia Refugees and Returnees Service (FDRE RRS) and subsequently from RRS regional office and camp coordination offices.
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Belay, H., Erko, B., Belachew, M. et al. Entomological survey of sand fly vectors and molecular screening for Leishmania parasite in refugee camps in Ethiopia.
Sci Rep (2026). https://doi.org/10.1038/s41598-026-37733-2
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DOI: https://doi.org/10.1038/s41598-026-37733-2
Keywords
- Ethiopia
- Phlebotomus rodhaini
- Refugee camps
Sergentomyia spp.- Vector surveillance
- Visceral leishmaniasis
Source: Ecology - nature.com
