Epidemiological and molecular investigation of resurgent cutaneous leishmaniasis in Sudan

Sarah Collis,Sayda El-Safi,Atia A Atia,Tapan Bhattacharyya,Awad Hammad,Margriet Den Boer,Hai Le,James A Whitworth,Michael A Miles

doi:10.1016/j.ijid.2019.08.018

Abstract

ObjectivesLocal health personnel have drawn attention to an apparent increase in incidence and severity of cutaneous leishmaniasis (CL) in Sudan. The objective of this study was to investigate CL burden and surveillance. MethodsSurveillance data were compiled from the KalaCORE programme, Leishmania coordinators in Northern Kordofan and Southern Darfur, and Khartoum Dermatology Hospital. CL lesions were sampled from 14 suspected cases from Northern Kordofan and the Hospital for Tropical Diseases in Omdurman. PCR–restriction fragment length polymorphism analysis and multilocus sequencing were used to characterize the disease agent. ResultsAll sites reported substantial increases from 2014 to 2016/7, far exceeding World Health Organization case reports for 2014, consistent with a widespread outbreak. Single seasonal peak incidence was observed, except for two peaks in Southern Darfur. In Northern Kordofan, the odds ratio for CL in the 35–44 years age group was 2.6 times higher than in the >45 years age group (p<0.0001); in Southern Darfur, the OR was 2.38 greater in males than females (p<0.0001). Lesions included severe presentations, despite chemotherapy. Leishmania major was identified as the agent. ConclusionsActive surveillance is required to understand the extent of CL in Sudan, as well as training to standardize surveillance, diagnosis, reporting, and quality control. Point-of-care rapid diagnosis would be valuable. Genotyping and phenotyping are required to monitor the emergence of pathogenic strains, drug resistance, outbreaks, and changes in severity.

Highlights

Cutaneous leishmaniasis (CL) is the most common form of the leishmaniases, which are caused by Leishmania protozoa
The 1350 cases seen at Khartoum Dermatology Hospital (KDH) alone in 2014 was more than the 1053 cases that the WHO reported in the same year for the entire country (World Health Organization, 2018b)
Between 2012 and 2016 there were consistently more cases among males than females, cumulatively 2178 (57.3%) male cases compared to 1599 female cases; sex was not recorded for 24 cases (Table 1)

Summary

Introduction

Cutaneous leishmaniasis (CL) is the most common form of the leishmaniases, which are caused by Leishmania protozoa. These are transmitted by female phlebotomine sand flies and principally affect impoverished and weakened populations. The agents of CL in eastern Africa are principally Leishmania tropica, Leishmania major, and Leishmania aethiopica, with different clinical outcomes. In Sudan, L. major, of the strain group named zymodeme LON-1, is considered commonly responsible for CL; L. tropica is known from neighbouring countries such as Egypt, Kenya, and Ethiopia (World Health Organization, 2010). Life-threatening visceral leishmaniasis (VL) is due to Leishmania donovani in eastern Africa and Leishmania infantum along the Mediterranean coast

Objectives

Methods

Results

Discussion

Conclusion