Background: Leishmaniases are parasitic diseases caused by Leishmania species and transmitted by the bite of sand flies. The genus Lutzomyia and Phlebotomus of sand flies are known to be the responsible vector for transmitting almost all Leishmania species to humans. The detection of Leishmania DNA in species of the genus Sergentomyia, in different regions, suggests their likely role in Leishmania transmission. Methods: Our objective was to determine the potential geographical distribution of Sergentomyia minuta, the most dominant Sergentomyia species in Morocco, using ecological niche modeling. Results: The results showed the widespread geographical distribution of S. minuta in Morocco, specifically in northern and central Morocco where visceral and cutaneous leishmaniasis foci occur. There were six abiotic factors affecting the distribution of S. minuta whose annual precipitation, precipitation seasonality and precipitation of driest month as the most important ecological variables of the model. Conclusion: A positive statistical correlation between human leishmaniasis cases and S. minuta abundance was noted suggesting the potential involvement of S. minuta in local Leishmania transmission cycles.

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Zoonotic visceral leishmaniasis is a common vector-borne systemic disease caused by Leishmania infantum (Kinetoplastida: Trypanosomatidae). In Morocco the situation is complex: many sandfly species have been collected in areas in which the disease is endemic, but only Phlebotomus ariasi, Phlebotomus perniciosus and Phlebotomus longicuspis (Diptera: Psychodidae) have been confirmed to have vectorial roles. The objective of the present study was to ascertain the potential distribution of L. infantum and its vectors in Morocco, using ecological niche modelling. Vector records were obtained from field collections of the Laboratory team and from previously published entomological observations. Epidemiological data for L. infantum modelling were obtained from Moroccan Ministry of Health reports. The jackknife test indicated that the bioclimatic variables with the greatest influence on model development for all species were annual precipitation and precipitation in the driest quarter of the year. MaxEnt model representations for sandfly species that act as vectors of L. infantum showed the widespread geographic distribution of these species in Morocco, specifically in northern and central Morocco, where foci of visceral leishmaniasis are found. The ecological niche modelling points out areas in which the probability of occurrence of these species is higher. This information should be considered as a starting point for further research to fully elucidate the ecology and epidemiology of these species, as well as of the pathogens they transmit.

Leishmaniasis is endemic in Morocco where both cutaneous and visceral forms coexist. To date, anthroponotic cutaneous leishmaniasis (ACL) determinants remain poorly investigated in Morocco. However, the disease risk factors identification is vital to determine the specific preventive process. In this aim, a case-control study was conducted in the main active ACL foci in central Morocco. Epidemiological data were extracted from bulletins, registers and annual reports of the regional direction of Health offices. The socioeconomic and environmental data were collected from epidemiological surveys, completed by a questionnaire intended for accessible positive population and control people selected from the cases’ entourage. The study included 258 cases and 395 controls. Our results showed that many socioeconomic factors were associated with ACL in Morocco such as the rural habitation (OR = 4.163; 95% CI: 2.91–5.96), movement to endemic area (OR = 4.53; 95% CI: 3.03–6.77), provenance from leishmaniasis foci (in Essaouira focus OR = 5.34; 95% CI: 1.19–24.03) and poverty. In addition, environmental factors like proximity of vegetation (OR = 2.45; 95% CI: 1.14–5.25), poor domestic hygiene, particularly the absence of sewage system/waste management (OR = 1.63; 95% CI: 1.35–1.96), and presence of animals (OR = 2.67; 95% CI: 1.14–5.25) increase the risk of ACL in Morocco. Except for Matrimonial status (married people, OR = 4.11; 95% CI: 1.80–9.41), there is however no significant association of the disease with the other socio-demographic factors in the study area (p>0.05). These several risk factors must be taken in consideration to prevent this disease through multidisciplinary collaboration and community participation.

The number of newly described sandfly-borne phleboviruses has been steadily growing in recent years. Some phleboviruses are human pathogens, but their health relevance is largely uncharacterized. We aimed to investigate the circulation of these viruses in the Emilia-Romagna region where several have already been described. A total of 482 sandflies were collected in a site in Reggio Emilia in 2019 and 2020. Sandflies collected in 2020 were grouped in 21 pools with a maximum of 25 sandflies per pool, submitted to real time PCR, and isolated in Vero cell culture. Complete genome sequencing showed the isolation of a strain of a Ponticelli III virus. This virus, which belongs to the species Adana phlebovirus, differed in the M segment from the Ponticelli I and Ponticelli II viruses. Analysis performed on the genomic segments of the newly isolated virus compared with other phleboviruses highlighted a strong purifying selection in the L segments, and different substitution saturation, highest in the M segments. Future research should address the ecological processes driving the occurrence of these novel phleboviruses and their possible impact on public health.