Leishmaniasis in Morocco: diseases and vectors

Epidemiological profile of visceral leishmaniasis in northern Morocco (2009-2018)

Introduction

visceral leishmaniasis (VL) represents the most serious and severe form of leishmaniasis in Northern Morocco. In this context, the objective of this study was to describe the epidemiological profile of VL in the Tangier Tetouan Al-Hoceima region from 2009 to 2018.

Methods

the epidemiologic data was collected from April 28th, 2019 to February 2nd, 2020 from files and investigation reports of cases. Additionally, annual reports for VL from the health services and provincial laboratories of parasitology were consulted. The analysis was conducted using statistical package for the social sciences (SPSS) v26 software.

Results

the study included 304 cases. Chefchaouen province was the highest endemic area (54.5%). The cases in the spring reached 36.5% and were characterized by age ≤5 years old (78.8%), male gender (M/F=1.3) and rural residents (91.4%). The number of inhabitants per household of cases was >5 persons (68.5%). A total of 94.3% and 98% had no suspect cases around or in their homes, respectively. Farmers accounted for 74.5% of cases. Signs of fever were present in 17.4% of cases, with 67.3% of these cases presenting these signs for a duration of more than 30 days. A total of 64.2% cases were diagnosed within a month. The serological test was used for diagnosis in 67.1% of cases and for the treatment, glunantime® was used in all cases (100%).

Conclusion

to eliminate the VL infection, it's necessary to monitor the entomological, mammalogical investigation. Also, to activate the Integrated Vector Control Management Committee at the most endemic province and to inform the community as well as the professionals of health about the VL control measures. A correlational study of the VL socio-economic and climate factors is recommended.

Epidemiological survey, molecular profiling and phylogenetic analysis of cutaneous leishmaniasis in Khyber Pakhtunkhwa, Pakistan

BACKGROUND

Cutaneous leishmaniasis (CL), an emerging vector-borne ailment in Khyber Pakhtunkhwa (KPK), Pakistan, exhibits diverse spread patterns and outbreaks.

METHODS

To comprehend its epidemiology and identify parasite species, we conducted an active survey on suspected CL cases (n=8845) in KPK.

RESULTS

Microscopy and internal transcribed spacer-1 PCR-restriction fragment length polymorphism (RFLP) molecular techniques detected Leishmania spp. in blood samples. Phylogenetic analysis gauged genetic affinities with other areas. District Bannu displayed the highest CL impact (14.58%), while Swat had the lowest impact (4.33%) among cases. Annual blood examination rate, parasite incidence and slide positivity rate were 4.96 per 1000 people, 0.0233 and 0.047%, respectively. CL infections were prevalent in 1- to 20-y-olds, with males (57.17%) more vulnerable than females (42.82%). Single lesions occurred in 43.73% of patients, while 31.2% people had two lesions, 17.31% had three lesions and 7.74% had more than three lesions. Most had sand-fly exposure but lacked preventive measures like repellents and bed nets. Leishmania tropica was confirmed via RFLP analysis in amplified samples. Phylogenetic analysis unveiled genetic parallels between L. tropica of KPK and isolates from China, Iran, Afghanistan, India, Syria and Morocco.

CONCLUSIONS

Urgent comprehensive control measures are imperative. Early detection, targeted interventions and raising awareness of CL and sand-fly vectors are vital for reducing the disease's impact. International collaboration and monitoring are crucial to tackle Leishmania spp.'s genetic diversity and curtail its cross-border spread.

Distribution and Ecology of Phlebotomine Sand Flies (Diptera: Psychodidae) in Endemic and Nonendemic Area of Leishmaniasis in Northern Morocco

Northern Morocco is endemic for cutaneous and visceral leishmaniasis. Our entomological investigations aim to evaluate the risk of Leishmania transmission by determining the species composition, the density, and seasonal fluctuation of sand fly populations in endemic and nonendemic areas of leishmaniasis in Tetouan province (North-Western Morocco). Using Sticky-paper traps, 8,370 specimens were collected between May and November 2015 in two localities: peri-urban area of Tetouan city, where leishmaniasis is endemic and that of the Oued Laou village where no cases of leishmaniasis have been recorded. Six sand fly species were identified. The genus Phebotomus was represented by five species: Phlebotomus ariasi, Phlebotomus. longicuspis, Phlebotomus perniciosus, Phlebotomus kazeruni, and Phlebotomus sergenti, while the genus Sergentomyia was represented by only one species Sergentomyia minuta. Phlebotomus perniciosus was dominant in the nonendemic area (47%) while Phlebotomus sergenti was dominant in the endemic area (51%). The spatio-temporal distribution of sand fly populations is discussed according to biotic and abiotic variables. Seasonal fluctuation in sand fly density showed a bimodal pattern for the subgenus Larroussius and a unimodal pattern for the subgenus Paraphlebotomus in Tetouan city. But, in Oued Laou village, a unimodal density distribution for species of the Larroussius subgenus and a bimodal seasonal distribution for species of the subgenus Paraphlebotomus were identified. We affirm the coexistence, in the study area, of vectors of both cutaneous and visceral leishmaniasis, namely P. ariasi, P. longicuspis and P. perniciosus vectors of Leishmania infantum and P. sergenti vector of L. tropica. However, the geographic distribution, the specific abundance, and the activity reveal significant differences between endemic and nonendemic areas in the region.

Ecological Survey of the Peridomestic Sand Flies of an Endemic Focus of Zoonotic Cutaneous Leishmaniasis in the South-East of Morocco

Leishmaniasis is a parasitosis caused by parasites of the genus Leishmania and is transmitted by Phlebotominae sand flies. An entomological survey was carried out in different localities of Zagora Province. Our work allowed us to establish an inventory of sand flies to study potential vectors of leishmaniasis and to compare the composition and the specific abundance of different endemic stations. The sand flies were collected using CDC miniature light traps during the month of July 2019 in the ten studied villages. The results indicate the presence of thirteen species, belonging to the genera Phlebotomus and Sergentomyia. Phlebotomus papatasi was the predominant species (46.65%) followed by Ph. alexandri (17%), Ph. longicuspis (11.55%), Ph. bergeroti (1.53%) and Ph. sergenti (1.27%). Phlebotomus kazeruni (0.03%) was rare, and only one female was captured in Ifred. Sergentomyia schwetzi (8.69%) was the most prevalent species in the Sergentomyia genus followed closely by Se. fallax (6.84%). Sergentomyia africana was present with a proportion of (3.86%) followed by Se. clydei (1.96%). Sergentomyia dreifussi (0.46%), Se. antennata (0.08%), and Se. minuta (0.08%) were very limited. Phlebotomus papatasi, Ph. alexandri, Ph. bergeroti, Ph. longicuspis, Ph. sergenti, Se. schwetzi, Se. clydei, and Se. fallax are constant species, being present at least in 50% of the stations (occurrence> 50%). Common species (25%–49%) were Se. minuta and Se. africana and rare species were Ph. kazeruni and Se. antennata with a very limited distribution (occurrence <12%). The greatest species richness was found in Ksar Mougni and Ifred with the occurrence of 11 species, but overall, it was high (>9 species) in most of the villages. The Shannon–Wiener index was high (H′ > 1) in eight localities (Ksar Mougni, Tassaouante, Bleida, ZaouiteLeftah, Ifred, Timarighine, Ait Oulahyane, and Ait Ali Ouhassou). The high value of this index is in favor of the ZaouiteLeftah locality (Shannon–Wiener index = 1.679) which is explained by the presence of a stand dominated by Ph. papatasi. In order to avoid exposure to infections, a good epidemiological surveillance and vector with rodent control measures must be well maintained. Awareness campaigns are also required and must be conducted for better knowledge of the disease.

Determinants of anthroponotic cutaneous leishmaniasis by case-control study in Morocco

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.

Climate Change Influences on the Potential Distribution of the Sand Fly Phlebotomus sergenti, Vector of Leishmania tropica in Morocco

BACKGROUND

Leishmaniases are a vector-borne disease, re-emerging in several regions of the world posing a burden on public health. As other vector-borne diseases, climate change is a crucial factor affecting the evolution of leishmaniasis. In Morocco, anthroponotic cutaneous leishmaniasis (ACL) is widespread geographically as many foci across the country, mainly in central Morocco. The objective of this study is to evaluate the potential impacts of climate change on the distribution of ACL due to Leishmania tropica, and its corresponding vector Phlebotomus sergenti in Morocco.

METHODS

Using Ecological Niche Modeling (ENM) tool, the estimated geographical range shift of L. tropica and P. sergenti by 2050 was projected under two Representative's Concentration's Pathways (RCPs) to be 2.6 and RCP 8.5 respectively. P. sergenti records were obtained from field collections of the laboratory team and previously published entomological observations, while, epidemiological data for L. tropica were obtained from Moroccan Ministry of Health reports.

RESULTS

Our models under present-day conditions indicated a probable expansion for L. tropica as well as for its vector in Morocco, P. sergenti. It showed a concentrated distribution in the west-central and northern area of Morocco. Future predictions anticipate expansion into areas not identified as suitable for P. sergenti under present conditions, particularly in northern and southeastern areas of Morocco. L. tropica is also expected to have high expansion in southern areas for the next 30 years in Morocco.

CONCLUSION

This indicates that L. tropica and P. sergenti will continue to find suitable climate conditions in the future. A higher abundance of P. sergenti may indeed result in a higher transmission risk of ACL. This information is essential in developing a control plan for ACL in Morocco. However, future investigations on L. tropica reservoirs are needed to confirm our predictions.

A conceptual model for understanding the zoonotic cutaneous leishmaniasis transmission risk in the Moroccan pre-Saharan area

Leishmanioses are of public health concern in Morocco, mainly the Zoonotic Cutaneous Leishmaniasis (ZCL) endemic in the Moroccan pre-Saharian area. Transmission of this disease depends on eco-epidemiological and socio-economic conditions. Therefore, a multivariable approach is required to delineate the risk and intensity of transmission. This will help outline main disease risk factors and understand interactions between all underlying factors acting on disease transmission at a local and regional scale. In this context, we propose a new conceptual model, the Biophysical-Drivers-Response-Zoonotic Cutaneous Leishmaniasis (BDRZCL), adapted to the Pre-Saharian area. The proposed model highlights how the physical and human drivers affect the environment and human health. The incidence of ZCL is linked to human activity and biophysical changes or by their interactions. The human response added to risk drivers are the main components that influence the biophysical part. This model improves our understanding of the cause-effect interactions and helps decision-makers and stakeholders react appropriately.

Epidemiology of the zoonotic malaria Plasmodium knowlesi in changing landscapes

Within the past two decades, incidence of human cases of the zoonotic malaria Plasmodium knowlesi has increased markedly. P. knowlesi is now the most common cause of human malaria in Malaysia and threatens to undermine malaria control programmes across Southeast Asia. The emergence of zoonotic malaria corresponds to a period of rapid deforestation within this region. These environmental changes impact the distribution and behaviour of the simian hosts, mosquito vector species and human populations, creating new opportunities for P. knowlesi transmission. Here, we review how landscape changes can drive zoonotic disease emergence, examine the extent and causes of these changes across Southeast and identify how these mechanisms may be impacting P. knowlesi dynamics. We review the current spatial epidemiology of reported P. knowlesi infections in people and assess how these demographic and environmental changes may lead to changes in transmission patterns. Finally, we identify opportunities to improve P. knowlesi surveillance and develop targeted ecological interventions within these landscapes.

Molecular characterization and genetic diversity of cutaneous leishmaniasis from North Eastern Pakistan

The genetic diversity of Leishmania spp. in North Eastern Pakistan remains undetermined despite increased cases of cutaneous leishmaniasis (CL). This study was designed to decipher the molecular characterization and genetic diversity of Leishmania spp. in North Eastern Pakistan. Out of 13761 CL suspected cases, 567 cases were microscopically positive and confirmed as Leishmania spp. by internal transcribed spacer (ITS) gene amplification through the PCR- RFLP technique. Further, isolates were directly sequenced to conduct phylogenetic analysis for genetic diversity. Among suspected CL cases, Mirpur showed the highest proportion of CL infection with 4.85% (118/2431) of the cases, while the Neelum district showed the lowest percentage at 3.29% (9/273). The slide positivity rate, annual blood examination rate, and annual parasite incidence rate were 3.84, 0.27, and 0.01% respectively, and the incidence of CL in the age group 1-20 years old was higher in males (50.92%) than females (25.75%). The RFLP analysis and sequencing confirmed the occurrence of Leishmania tropica, Leishmania major, and Leishmania infantum. Leishmania tropica (p = 0.02) confirmed significantly higher nucleotides variation than L. major (p = 0.05). Current findings confirmed the prior assumption that anthroponotic CL is the primary CL form present in North Eastern Pakistan. Moreover, this is the first report based on molecular identification of L. major, and L. infantum from North Eastern Pakistan. This remarkable heterogeneity in the Leishmania spp. is the leading cause of treatment failure and emergence of new haplotypes. Therefore more extensive investigations are recommended from all geographical regions of North Eastern Pakistan, especially those using a large sample size.

Potential distributions of phlebotomine sandfly vectors of human visceral leishmaniasis caused by Leishmania infantum in Morocco

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.

Sand Flies Control: A Review of the Knowledge of Health Professionals and the Local Community, Province of El Hajeb, Morocco

Sand flies are insect vectors of several diseases including leishmaniases. These vector-borne diseases represent a public health problem in several countries around the world, including Morocco. The objective of this study was to assess simultaneously the knowledge of health professionals and inhabitants on sand flies; a cross-sectional survey was conducted between April and June 2019 among 424 people, 34% of whom were health professionals and 66% of whom were inhabitants of the province of El Hajeb in central Morocco; 46.3% of doctors, 50.7% of nurses, 66.7% of midwives and 69.4% of inhabitants showed a low knowledge of sand flies. Most participants believed that sand flies breed in stagnant and polluted waters. Negative attitudes were found among 72.2% of the inhabitants. Factors associated with a high level of knowledge included continuing education among health professionals and information on vector-borne diseases among residents. The conceptual and cognitive gaps in the knowledge of sand flies reflect the lack of information and training on sand flies. The results of the sand fly knowledge review can be integrated into the national leishmaniases control program and the integrated vector management strategy to raise public awareness on the health risks of sand flies.

Population structure of leishmania major in southeastern morocco

Cutaneous leishmaniasis (CL) is an infectious disease caused by various Leishmania species. It is among the most neglected tropical diseases and has been considered a major health threat over the past decades in the country. Its zoonotic form caused by Leishmania (L) major is the most prevalent in Morocco. This study investigated the population structure of L. major in southeastern Morocco. Samples (n = 67) were collected from patients with CL in five different endemic areas located in three provinces (Ouarzazate, Tinghir, and Zagora). These samples were then sequenced using two nuclear markers: internal transcribed spacer 1 (ITS1) and a fragment of the virulence factor GP63. Next, the sequences were edited and analyzed. Molecular diversity indices showed a high population genetic diversity but an overall low haplotype diversity. Our results suggest small population differentiation, indicating a low geographic structure. Tajima's D and Fu's Fs tests both suggested recent population expansion based on the significant deviations from neutrality in both tests for all populations except Tinghir, which may be due to a small sample size. Based on our findings, the region is experiencing rapid population expansion caused by recent CL outbreaks, and one of them has been recently studied. In addition, analysis of molecular variance and F_ST suggested gene flow between Zagora and both Ouarzazate and Tinghir. Nonetheless, no gene flow was observed between Tinghir and Ouarzazate. To the best of our knowledge, this is the first analysis of the population structure of L. major in Morocco. The results of this study provide crucial background information for epidemiological studies by showing the presence of gene flow between populations and clonal expansion in cases of an outbreak. This will drive authorities to reconsider the implemented control strategies.

First molecular detection and identification of Leishmania species in small wild rodents from Turkey

Leishmaniasis is a parasitic disease infecting animals and humans. Two clinical forms (Visceral and cutaneous leishmaniasis) and four species are reported to be present in Turkey. Several studies have investigated canine and human leishmaniasis in Turkey but no study was performed to screen the infection among wild rodents, so far. The present study aims to investigate the role of small wild rodents as reservoir animals for Leishmania spp. in different regions of Turkey. Formalin-preserved tissue samples (spleen, liver, lung) of 712 rodents from 30 provinces were screened for the presence of Leishmania spp. DNA. Before DNA extraction, tissues were dried, rehydrated, and homogenated. Leishmania screening in rodent tissues and species determination was performed with a combination of real-time kDNA and ITS1 polymerase chain reaction protocols. Eight (1.12%) out of 712 animals were found to be positive for Leishmania spp. DNA and species typing revealed five L. infantum, two L. tropica and one L. major among positives. Leishmania major and L. infantum DNA were detected in Apodemus spp. from Zonguldak province located in the Western Black Sea Region, while L. tropica DNA was found in Meriones sp. and Gerbillus dasyurus from Adana and Hatay provinces located in Eastern Mediterranean Region of Turkey. The present study is first to report natural infection of L. infantum, L. major and L. tropica in small wild rodents in Turkey, suggesting their possible roles as reservoirs. Further studies are needed for planning epidemiological studies and also for developing rodent control measures in risky endemic areas to break the transmission cycle.

Management of Leishmaniases in the Era of Climate Change in Morocco

The proliferation of vector-borne diseases are predicted to increase in a changing climate and Leishmaniases, as a vector-borne diseases, are re-emerging diseases in several regions of the world. In Morocco, during the last decade, a sharp increase in cutaneous leishmaniases cases has been reported. Nevertheless, in Morocco, leishmaniases are a major public health problem, and little interest was given to climate change impacts on the distribution and spread of these diseases. As insect-borne diseases, the incidence and distribution of leishmaniases are influenced by environmental changes, but also by several socio-economic and cultural factors. From a biological point of view, environmental variables have effects on the survival of insect vectors and mammalian reservoirs, which, in turn, affects transmission. Here, we highlight the effects of climate change in Morocco and discuss its consequences on the epidemiology of leishmaniases to identify challenges and define targeted recommendations to fight this disease.

Molecular detection of Leishmania infantum DNA and host blood meal identification in Phlebotomus in a hypoendemic focus of human leishmaniasis in northern Algeria

BACKGROUND

Leishmania parasites are transmitted by female phlebotomine sand flies that maintain the enzootic cycle by circulating between sylvatic and domestic mammals. Humans are part of this cycle as accidental hosts due to the vector's search for a source of blood. In Algeria, Human Leishmaniases (HL) are endemic and represent a serious public health problem because of their high annual incidence and their spread across the country. The aim of this study is to identify sand fly species fauna (vectors of Leishmania), determine their infection rate and identify their feeding preferences using molecular tools in a hypoendemic focus of HL located in the province of Tipaza, northern Algeria.

METHODOLOGY/PRINCIPAL FINDINGS

An entomological survey using CDC light traps was conducted between July and October of 2015 in four HL affected peri-urban locations in the province of Tipaza, northern Algeria. Sand flies were identified using the morphological criteria of the genitalia for the males and spermathecae for the females. Leishmania DNA was detected in pooled female sand flies (N = 81 pools with 8-10 specimens per pool) using quantitative real-time polymerase chain reaction (qPCR) targeting two different genes: kDNA-PCR and 18S rRNA. To identify their blood meal sources, blood-fed female sand flies were analyzed by PCR-sequencing targeting the vertebrate cytochrome c oxidase I (COI) gene. A total of 4,045 sand flies were caught, of which 3,727 specimens were morphologically identified. Seven species were recorded: P. (L.) perniciosus (50.28%), P. (L.) perfiliewi (26.13%), P. (L.) longicuspis (21.92%), Sergentomyia (S.) minuta (0.85%), P. (P.) papatasi (0.42%), P. (L.) langeroni (0.32%) and P. (L.) ariasi (0.05%). Afterwards, 740 female specimens were randomly selected and divided into 81 pools and were then screened to investigate the presence of Leishmania spp. L. infantum DNA was detected in three pools, corresponding to three sand fly specimens (one each). The infection rate was 0.33% (2/600) for P. (L.) perniciosus and 2.56% (1/39) for P. (L.) perfiliewi. Analysis of the blood feeding sources (N = 88 specimens) revealed that sand flies belonging to Larroussius subgenera, mainly (71.5%) feed on small ruminants. Human blood is the second feeding source (17%), eight specimens (9%) were found to feed on equines and no domestic reservoir (dog) blood was found.

CONCLUSIONS/SIGNIFICANCE

The presence of human leishmaniasis cases, the high abundance of Phlebotomus (Larroussius) species which are proven or suspected vectors of L. infantum, and the detection of L. infantum DNA from its natural vectors (P. (L.) perniciosus, P. (L.) perfiliewi), in addition to the blood-feeding of positive females for L. infantum on humans blood, prove that the major elements of the epidemiological transmission cycle of L. infantum are present and indicate risk factors for an outbreak of the disease in the province of Tipaza.

Risk factors and prediction analysis of cutaneous leishmaniasis due to Leishmania tropica in Southwestern Morocco

Cutaneous leishmaniasis is currently a serious public health problem in northern Africa, especially in Morocco. The causative parasite is transmitted to a human host through the bite of infected female sandflies of the genus Phlebotomus. The objective of the present study is to characterize the causative organisms and to predict the risk of cutaneous leishmaniasis (CL) cases in six provinces in southwestern Morocco, based on the spatial distribution of cases in relation to environmental factors and other risk factors such as socio-economic status and demographics. A molecular study was carried out using ITS1 PCR-RFLP method of the ribosomal DNA of Leishmania. An epidemiological study on CL cases was reported between 2000 and 2016 in this current investigation in six provinces in southwestern Morocco. Statistical analysis was performed using a linear regression model to identify the impact as well as the interaction between all predictor variables on the distribution of CL in the studied provinces. The forecast Holt-Winters (HW) method was used to describe the trend and seasonality of CL cases. The ITS1-PCR- RFLP analysis revealed the presence of Leishmania tropica in all studied provinces. The spatial distribution of CL cases documented in all studied provinces during the sixteen years showed a heterogeneous pattern and fluctuation trend with an average prevalence of 9.92 per 100,000 inhabitants. In addition, the forecast HW model predicts continued variability of trend and seasonality of CL cases in the upcoming years. This study confirmed the importance of socioeconomic factors, in particular poverty and the vulnerability rate, on distribution and emergence of CL. This study revealed a relationship between increasing risk of CL occurrence due to Leishmania tropica, as well as the distribution and emergence thereof, and socioeconomic factors in the investigated area.

Canine Leishmania infantum infection: an imported case in UK after staying in the Canary Islands

Leishmaniosis is reported in the Iberian Peninsula and the Balearic Islands, but the Canary Islands are deemed free. In the present communication, we report a clinical leishmaniosis due to Leishmania infantum in a dog that was presumptively infected during its stay on Tenerife. The result of Leishmania serology (whole-cell based ELISA with L. infantum antigen) was high positive (test score of 82.2 at a cut-off value of 12.0). This result was further confirmed with quantitative real-time polymerase chain reaction (qPCR) for Leishmania spp. on a blood sample. A medium load of parasites was detected (48 parasites/ml blood). L. infantum was identified by RFLP analysis of the ITS-1 PCR product. Confirmation that leishmaniosis is endemic to the Canary Islands would further require study on local dogs with no travel history as well as reassessment on frequency and distribution of Phlebotomus spp. as well as Leishmania spp. detection in the sand fly vector. However, this case strongly suggests that L. infantum is present on the Canary Islands. Although transmission seems to be still exceptional, preventive measures in dogs travelling to the Canaries should be considered.

Molecular detection of Leishmania infantum and Leishmania tropica in rodent species from endemic cutaneous leishmaniasis areas in Morocco

Background

Leishmaniasis remains a major public health problem in African nations, including Morocco, where little is known about the vertebrate reservoirs involved in the causal parasites’ transmission cycles. The present study investigates the role of rodent species as potential reservoirs of Leishmania spp. in central Morocco, where both L. tropica and L. infantum have been reported.

Methods

Rodents were caught from 22 sites in central Morocco, by using Sherman metal traps, and identified morphologically. For each specimen, genomic DNA was extracted from different tissues using the Speed Tools DNA extraction Kit. Then, samples were PCR-analyzed, targeting the SSU rRNA gene to detect Leishmania spp. DNA, followed by amplification of the internal transcribed spacer 1 (ITS1) and its sequencing to identify the species.

Results

A total of 197 rodents belonging to ten species were captured and identified: Rattus rattus (40.61%), Mus musculus (25.38%), Apodemus sylvaticus (8.63%), Mus spretus (7.11%), Meriones shawi (5.58%), Rattus norvegicus (4.57%), Meriones libycus (3.05%), Mastomys erythroleucus (2.03%), Gerbillus campestris (2.03%) and Lemniscomys barbarus (1.01%). Molecular analysis revealed the presence of Leishmania species in 18 specimens: six R. rattus (out of 80 captured; 7.5%), 11 M. musculus (out of 50 captured; 22%), and one R. norvegicus (out of 9 captured; 11.11%).

Conclusions

To the best of our knowledge, L. infantum and L. tropica were identified in rodent species for the first time in Morocco. These findings suggest that rodent species may be involved in L. infantum and L. tropica transmission cycles in this country but that further studies are needed to confirm their role as reservoirs of Leishmania species in Morocco.

Electronic supplementary material

The online version of this article (10.1186/s13071-017-2398-8) contains supplementary material, which is available to authorized users.

New epidemiological pattern of cutaneous leishmaniasis in two pre-Saharan arid provinces, southern Morocco

Three Leishmania species are responsible of cutaneous leishmaniasis (CL) in Morocco. Zoonotic CL due to Leishmania major and Leishmania infantum, the first is known as established in the eastern arid regions, whereas the latter evolves sporadically, especially in the North. While Leishmania tropica, classically considered anthroponotic, is endemic in the semi-arid regions and is largely distributed throughout the country. The aim of this study was to identify the Leishmania species causing CL in two Provinces in arid pre-Saharan region known as zoonotic CL foci, and to contribute an update to the national data concerning the distribution of Leishmania species in both regions. The recruitment of patients was done in six localities in Ouarzazate and Zagoura provinces in 2015 and 2016. Out of 81 samples collected, 66 were positive (81%) by ITS1-PCR amplification of Leishmania DNA extracted from stained smears. The highest rate of Leishmania infection was registered in children aged 9 years or less (71,2%). The ITS1-PCR- RFLP analysis revealed the predominance of L. major infecting 52 patients (79%), followed by L. tropica in 12 patients (18%) and L. infantum in 2 patients who had no history of travel outside the studied area (3%). The sequencing of the ITS1 of both L. infantum, showed 100% similarities with L. infantum strains isolated from dogs and visceral leishmaniasis patients from the south and north of Morocco. The coexistence of the 3 Leishmania species in the same focus, and the difficult distinction of infections associated to the different Leishmania species based only on clinical lesions' aspects complicate the diagnosis and then the national control strategy, as well as the therapeutic management. The epidemiological pattern of CL in the studied areas appears to have changed during the last decades, from a predominant zoonotic CL caused by L. major to a polymorphic disease that can be due to any of the 3 Leishmania species. The expansion of L. infantum and L. tropica in southern parts of Morocco, calls for in depth epidemiological investigations for a better understanding of the CL situations in Southern parts of the country and for an assessment of the climate impact and environment changes on the leishmaniasis transmission system.

Urbanization of human visceral leishmaniasis in Morocco

Human visceral leishmaniasis one of the seven most neglected tropical diseases in the world. In Morocco, HVL is widespread in all regions; but it is more common in the northern part with sporadic cases observed in the South.

During the period between 2004 and 2013, the most affected Moroccan provinces were Taounate province, with 220 cases (16.09% of all cases), followed by Chefchaouen with 13.17% and Taza with 10.46% of the total cases. Children < 5 years old are the most affected age group, most cases registered were male.

Geographic distribution of HVL showed predominance in rural areas but we noted that it's opening to be urban.

Epidemiological characteristics of visceral leishmaniasis in Morocco (1990-2014): an update

Leishmaniases are parasitic diseases frequent in the Mediterranean Basin. Visceral leishmaniasis (VL) is a notifiable parasitic disease that increased in incidence in Morocco over the past few years and has recently emerged in several new foci, causing a public health problem in Morocco. The aim of this study is to describe the spatio-temporal distribution of VL in Morocco between 1990 and 2014 period in order to highlight important features and trends of VL and its epidemiology and to assess whether the activity of the unit reflects the situation of the disease at the national level and whether it could constitute an indicator of public health relevance. Two thousand four hundred and twenty one cases were reported in Morocco between 1990 and 2014 with an average annual reported incidence rate of 0.4 cases per 100.000 inhabitants. Before 1996 the average annual incidence of VL was 50 cases on average. After this date the number of cases increased and then remained stable with around 100-150 cases per year. Children whose age varies between 1 and 4 years old are the most affected with 1327 (74%) of total cases; nevertheless the adult starts to be affected by the disease. In 2000, 65% of positive cases of VL are concentrated at both northern regions: Taza-Al Hoceima- Taounate with 45% of cases, Tanger- Tetouan mainly represented by Chefchaoun with 20% of cases. The Fez-Boulemane region located in the center recorded 12% of cases. Throughout the years the map VL distribution has been progressively changed and spatial spread of the disease to the center is noted in 2007. 2014 has been marked by an even greater extension of the disease to the center and south of Morocco. Nationally in 2014, 34 of 75 provinces and prefectures are affected compared to 2000, when 22 out of 82 provinces and prefectures were affected. Leishmania infantum was identified the causative agent based on species- specific PCR-Lei70 assay. VL remains a sporadically endemic parasitic disease in Morocco with a progressive extension of its range of distribution. Such a situation would relate to the geographical succession of Phlebotomine sand fly vectors, the difficulty of actions against the canine population reservoirs of L. infantum and unfavorable socio-economic factors.

Spatial patterns and secular trends in human leishmaniasis incidence in Morocco between 2003 and 2013

BACKGROUND

Few studies on spatial patterns or secular trends in human leishmanias have been conducted in Morocco. This study aimed to examine spatial patterns and trends associated with the human leishmaniasis incidence rate (HLIR) at the province/prefecture level between 2003 and 2013 in Morocco.

METHODS

Only the available published country data on the HLIR between 2003 and 2013, from the open access files of the Ministry of Health, were used. Secular trends were examined using Kendall's rank correlation. An exploratory spatial data analysis was also conducted to examine the spatial autocorrelation (Global Moran's I and local indicator of spatial association [LISA]), and spatial diffusion at the province/prefecture level. The influence of various covariates (poverty rate, vulnerability rate, population density, and urbanization) on the HLIR was tested via spatial regression (ordinary least squares regression).

RESULTS

At the country level, no secular variation was observed. Poisson annual incidence rate estimates were 13 per 100 000 population (95 % CI = 12.9-13.1) for cutaneous leishmaniasis (CL) and 0.4 per 100 000 population (95 % CI = 0.4-0.5) for visceral leishmaniasis (VL). The available data on HLIR were based on combined CL and VL cases, however, as the CL cases totally outnumbered the VL ones, HLIR may be considered as CL incidence rate. At the provincial level, a secular increase in the incidence rate was observed in Al Hoceima (P = 0.008), Taounate (P = 0.04), Larache (P = 0.002), Tétouan (P = 0.0003), Khenifra (P = 0.008), Meknes (P = 0.03), and El Kelaa (P = 0.0007), whereas a secular decrease was observed only in the Chichaoua province (P = 0.006). Even though increased or decreased rate was evident in these provinces, none of them showed clustering of leishmaniasis incidence. Significant spatial clusters of high leishmaniasis incidence were located in the northeastern part of Morocco, while spatial clusters of low leishmaniasis incidence were seen in some northwestern and southern parts of Morocco; there was spatial randomness in the remaining parts of the country. Significant clustering was seen from 2005 to 2013, during which time the Errachidia province was a permanent 'hot spot'. Global Moran's I increased from 0.2844 (P = 0.006) in 2005 to 0.5886 (P = 0.001) in 2011, and decreased to 0.2491 (P = 0.004) in 2013. It was found that only poverty had an effect on the HLIR (P = 0.0003), contributing only 23 % to this (Adjusted R-squared = 0.226).

CONCLUSION

Localities showing either secular increase in human leishmaniasis or significant clustering have been identified, which may guide decision-making as to where to appropriately allocate funding and implement control measures. Researchers are also urged to undertake further studies focusing on these localities.

Species composition of sand flies and bionomics of Phlebotomus papatasi and P. sergenti (Diptera: Psychodidae) in cutaneous leishmaniasis endemic foci, Morocco

Background

Cutaneous Leishmaniasis (CL) is one of the most neglected tropical diseases in Morocco. Leishmania major and L. tropica are the main culprits identified in all endemic foci across the country. These two etiological agents are transmitted by Phlebotomus papatasi and P. sergenti, the two most prevalent sand fly species in Morocco. Previous studies reflected gaps of knowledge regarding the environmental fingerprints that affect the distribution of these two potential vectors across Morocco.

Methods

The sand flies were collected from 48 districts across Morocco using sticky paper traps. Collected specimens were preserved in 70 % ethanol for further processing and identification. Male and female densities were calculated in each site to examine their relations to the environmental conditions across these sites. The study used 19 environmental variables including precipitation, aridity, elevation, soil variables and a composite representing maximum, minimum and mean of day- and night-time Land Surface Temperature (LST), and Normalized Difference Vegetation Index (NDVI).

Results

A total of 11,717 specimens were collected during this entomological survey. These specimens represented 11 species of two genera; Phlebotomus and Sergentomyia. Correlations of the sand fly densities with the environmental variables were estimated to identify the variables which influence the distribution of the two potential vectors, Phlebotomus papatasi and P. sergenti, associated with all CL endemic foci across the country. The density of P. papatasi was most affected by temperature changes. The study showed a significant positive correlation between the densities of both sexes of P. papatasi and night-time temperatures. Both P. papatasi and P. sergenti showed a negative correlation with aridity, but, such correlation was only significant in case of P. papatasi.

NDVI showed a positive correlation only with densities of P. sergenti, while, soil PH and soil water stress were negatively correlated with the densities of both males and females of only P. papatasi.

Conclusions

Our results identified the sand fly species across all CL endemic sites and underlined the influences of night-time temperature, soil water stress and NDVI as the most important variables affecting the sand fly distribution in all sampled sites. This preliminary study considered the importance of these covariates to anticipate the potential distribution of P. papatasi and P. sergenti in Morocco.

Electronic supplementary material

The online version of this article (doi:10.1186/s13071-016-1343-6) contains supplementary material, which is available to authorized users.

Spatial relations among environmental factors and phlebotomine sand fly populations (Diptera: Psychodidae) in central and southern Morocco

Phlebotomine sand flies (Diptera: Psychodidae, Phlebotominae) are of considerable public health importance because of their ability to transmit several human parasites, mainly as vectors of Leishmania spp. Over the past decade, the epidemiological situation of cutaneous leishmaniasis (CL) has significantly increased with its geographic expansion to previously free areas and the emergence of overlapping foci of cutaneous leishmaniasis and visceral leishmaniasis (VL) in several provinces of Morocco. A total of 15,313 specimens was collected during this entomological survey. The genera Phlebotomus (57.38%) and Sergentomyia (42.62%) were identified. Sergentomyia minuta (22.01%) was the most prevalent species, followed by S. fallax (18.21%), Phlebotomus perniciosus (14.35%), P. papatasi (14.06%), P. sergenti (12.85%), P. longicuspis (10.74%), P. ariasi (2.68%), S. dreyfussi (1.53%), P. alexandri (1.31%), P. bergeroti (1.14%), S. christophersi (0.62%), S. africana (0.25%), P. chabaudi (0.14%), P. chadlii (0.05%), and P. kazeruni (0.04%). We aimed to determine current distribution of leishmaniases vectors, their ecological characteristics, and the significance of the predominant species at any bioclimate stage, altitude range, and soil texture in terms of the risk of leishmaniasis transmission.

Species composition of phlebotomine sand fly fauna in an area with sporadic cases of Leishmania infantum human visceral leishmaniasis, Morocco

Visceral and cutaneous leishmaniases are the main endemic vector-born diseases in Morocco. Human visceral leishmaniasis (HVL), by Leishmania infantum, currently presents a significant health problem throughout the country and may constitute factor for death, especially among children with less than 15 years old. In the past, HVL has been basically absent or at least sporadic in Marrakesh-Tensift-Al Haouz region; however it became significant during the last decade. An entomological survey and a retrospective study on L. infantum HVL cases had been carried out to assess the risk of the disease apparition in this region. 7046 sand flies (Diptera: Psychodidae) were collected and studied from twelve localities within Marrakesh-Tensift-Al Haouz region. The result shows the presence of ten sand fly species, 58.76% from the genus Phlebotomus and 41.24% from genus Sergentomyia. A further analysis indicates that Phlebotomus perniciosus, Phlebotomus longicuspis and Phlebotomus ariasi species, incriminated vectors of L. infantum, are dominant (35.56%), so, we describe their spatial (according to altitude and biotopes) and temporal (seasonal activity) distribution in study area.