Risk factors for the expansion of cutaneous leishmaniasis by Leishmania tropica : Possible implications for control programmes

Abstract

Cutaneous leishmaniasis (CL) caused by Leishmania tropica is emerging in new areas, initially as outbreaks and then establishing endemic foci. There is little evidence of the risk factors and effectiveness of existing control measures, what limits our ability to generalize in different epidemiological settings. The disease is described as anthroponotic; however, zoonotic outbreaks have been reported in some countries. Our aim was to identify risk factors in a recently reported endemic focus in Morocco in order to design more effective control programmes. A case-control study was conducted from September 2014 to October 2015 for epidemiological data collection from families with and without CL cases. Sandflies were captured and L. tropica infection determined. The presence of potential animal reservoirs was evaluated. 71 CL cases (44 diagnosed between 2013 and 2015) and 137 healthy people were surveyed. The average age of the new cases was 33.1 ± 22.3 years, and 69.0% were women. Phlebotomus sergenti was the most abundant species with a density of 4.27 sandflies/trap/night and differences between houses with and without CL cases were detected (p-value = 0.014). Overall, 2.7% female P. sergenti and 3.0% dogs were positive for L. tropica. Human, cat, rabbit and bird blood was detected in blood-fed P. sergenti females. 45% people used preventive measures that were not translated into a reduction in the individual risk of acquiring CL. Exposure to P. sergenti was the only risk factor found, and the reduction in its density could be achieved through the improvement of water wells management, organic fertilizers' disposal and dogs control. The lack of effectiveness of indoor residual spraying and treated nets are attributable to poor compliance and misuse of them. In addition, result optimization of the awareness campaigns on the public is possible by involving patients with CL to explain their own experience.

Expansion of urban cutaneous leishmaniasis into rural areas of southeastern Iran: Clinical, epidemiological and phylogenetic profiles explored using 7SL high resolution melting‐PCR analysis

“…Contrary to the urban type, the presence of confounding determinants has allowed ACL to extend into rural areas (Aflatoonian et al, ; Sharifi, Poursmaelian, et al, ). Numerous risk factors have contributed to the emergence of new CL outbreaks in Pakistan (Hussain et al, ,), Syria (Al‐Salem et al, ; Saroufim et al, ), Morocco (Fatima et al, ; Gijón‐Robles et al, ) and Israel (Gandacu et al, ).…”

Psychological and Social Burden of Cutaneous Leishmaniasis Among the Residents of Quetta City, Pakistan

“…People who are looking after cattle and other animals are usually at higher risk. All these may act as harbour for sand-flies, which has been confirmed by various studies [19] [23]. A study showed that house ceilings made up of old wood might act as shelter for the sand-fly and significant CL cases were observed in such houses [27].…”

“…What they fail to acknowledge is that, if left untreated, lesions may be superinfected and cause extreme disfigurement, with physical, mental, social, and psychological consequences. In many instances, women do not seek medical care during hospital hours due to their housework demands [23].…”

Understanding the factors that determine the emergence of anthroponotic cutaneous leishmaniasis due to Leishmania tropica: Comparison of the density and mitochondrial lineage of Phlebotomus sergenti between endemic and free areas in Morocco

“…In El Borouj, L. tropica DNA was detected in 5 out of 184 (2.7%) female P. sergenti (Gijón-Robles et al, 2018) in captures made throughout 2014 (4+/72: 5.6% and up to 18,000 parasites/μg DNA; data not shown) and 2015 (1+/112: 0.9%). The five positive L. tropica females belonged to the most prevalent P. sergenti lineage in El Borouj, lineage IV.…”

“…The female P. sergenti from El Borouj in which L. tropicaDNA was detected was identified as a lineage IV specimen. In addition, 4 positive females for L. tropica from captures made in 2014 (Gijón-Robles et al, 2018) were also identified as lineage IV.…”