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Cutaneous leishmaniasis (CL) has been described in West Africa (WA) since the beginning of the 20th century. The incidence of cases has markedly increased during the last decades in several countries of the region. Despite that, data remain scarce and fragmentary. The current incidence and geographic distribution of the disease as well as the involved vectors and reservoirs remain poorly documented. The objective of this review was to collect and analyze available data about CL in WA in order to improve the management of cases and the control of the disease transmission. A systematic literature review was performed using the Pubmed, Google Scholar and Hinari databases. Publications focusing on epidemiological aspects of CL, involved parasite species, sand flies and potential reservoir hosts were searched without any restrictions. Unpublished studies were extracted from Google. Manuscripts without full text or summary available were excluded as well as those whose summaries did not contain any usable data. One hundred and fifteen studies were recorded. Among them, 93 filled selection criteria. CL has been reported in 10 West African countries with outbreaks described in five countries. Burkina Faso, where the average incidence of the disease is around 928 cases per year, and Ghana seem to be the most affected. Cases have been confirmed in the majority of studies by microscopy sometimes associated with culture or histology. The exposure rate to Leishmania infection based on leishmanin skin test was relatively high with an overall average of 30.2%. Leishmania major was the only species identified with a predominance of MON-74 (62%) and MON-26 (30.6%) zymodemes. Phlebotomus duboscqi is retained as the vector whereas Sergentomyia darlingi and Sergentomyia ingrami were found naturally infected. Rodents including Arvicanthis niloticus, Gerbilliscus gambiana and Mastomys spp. are reported as the main reservoir hosts. Additional studies are needed to better characterize CL in WA in order to optimize the management of cases and to organize the control of the disease transmission., Competing Interests: The authors have no conflicts of interest to declare

The aim of this study was to assess the performance of real-time PCR (qPCR) in the diagnosis of cutaneous leishmaniasis (CL). Culture, direct microscopic examination (DE) and qPCR were performed on dermal exudate samples collected from 235 confirmed CL cases. The qPCR was found to be more sensitive than other diagnostic techniques and was able to correct the diagnosis in 49 patients (20.9%) with negative dermal smears. Median parasitic load (PL) of the 49 dermal exudates with negative DE was lower than that of positive ones in microscopy. This suggests that PL likely impact the sensitivity of microscopy. On the other hand, qPCR was performed on DNA extracts of scraped products collected from the 23 out of 49 archived negative Giemsa-stained slides and showed 11 positive. Parasitic loads in the latter smears were lower than those in corresponding exudates. The results highlight qPCR relevance for the diagnosis of CL and recommend its use directly on dermal exudates collected from CL lesions., Competing Interests: The authors have no conflicts of interest to declare

The purpose of our study was to report the particularities of the management of toxoplasmosis seroconversion cases occurred during the third trimester of pregnancy and diagnosed in the Institute Pasteur of Tunis. The study was conducted in the Laboratory of Parasitology-Mycology of the Institute Pasteur of Tunis between January 2005 and December 2017. A total of 27 cases of toxoplasmosis seroconversion during the third trimester were included. Prenatal diagnosis was performed in five cases. PCR was positive in one case. Pyrimethamine-sulfadoxine was prescribed in one case with positive PCR and in another case as soon as maternal infection was confirmed. Spiramycine was prescribed in 24 cases for the duration of the pregnancy. One woman did not take any treatment because seroconversion was diagnosed just before delivery. Twenty newborns had congenital toxoplasmosis: 19 cases were diagnosed by serology and one case was diagnosed after amniocentesis. Two newborns (10%) were symptomatic at birth. All the newborns had neither clinical nor radiological signs during the follow-up., Competing Interests: The authors have no conflicts of interest to declare

Cutaneous leishmaniasis (CL) remains highly endemic in Tunisia. The governorate of Kairouan (Center) is one of the most affected particularly by zoonotic form due to Leishmania major. The purpose of this study was to describe the epidemiological, clinical and therapeutic features of the disease in this governorate and to identify any particularities in children. Three hundred and ninety cases were registered over 2 years (2012 and 2013). The average age was 29 years one month [± 22.7] (34.6% of patients were under 15 years). The cumulative incidence of CL was equal to 34.4 per 100,000 per year. It was higher in children (39.6 per 100,000 versus 29, p=0.004). Cases were diagnosed especially in autumn and winter (88.3% of cases between October and January, p<0.001). The average delay of consultation was one month and 22 days [± 2.5] after onset of lesions. The average number of lesions per patient was 2.7 [± 2.3] with a mean diameter equal to 2.2 cm. In addition to a higher incidence of the disease, two other features were found in "Children" group which are the presence of similar cases in the neighborhood (27.7% versus 13.4%, p=0.002) and preferential localization in the face (36.4% versus 11%) while the members were more affected in adults (63.5% versus 46.4%) (p<0.001). Meglumine antimoniate was prescribed for most of our patients (93.1%). The intramuscular route was used more than local one, probably because of high proportions of multiple lesions and facial localization.

Visceral leishmaniasis (VL) is an important health problem in Tunisia. It is most common in children under five years of age. The governorate of Kairouan (central Tunisia) is one of the most affected foci. The aim of this study was to update the epidemiological, clinical and biological features of the disease. The study concerned all VL cases admitted in the pediatric department of Kairouan hospital during 10 years (from 2004 to 2013). For every patient included in this study and when available, data such as sex, age, geographical origin and the condition of the patient at admission (clinical and biological findings) were collected. The myelogram results were also exploited as well as results of serology, culture, Real-Time polymerase chain reaction (PCR) and isoenzymatic typing of Leishmania isolates. Two hundred and forty cases were recorded. Rural cases (87.1%) were more prevalent than urban ones (12.9%). Age ranged from 2 months to 13 years (median, 18 months). The female/male sex ratio was 1.03. The diagnosis delays ranged from 1 day to 8 months (median, 15 days). The most common clinical symptoms at admission were splenomegaly (97.9%), fever (79.9%) and hepatomegaly (47.3%). The principal biological disturbances were anemia (91.7%), thrombocytopenia (83.9%) and leucopenia (56.1%). Among the different biological tools used for diagnosis confirmation, PCR was the most sensitive (100%). All 43 typed stocks corresponded to Leishmania (L.) infantum species. Although zymodeme MON-1 was predictably the most frequent (27 cases), L. infantum MON-24 and MON-80 were responsible of no negligible numbers of cases (11 and 5 cases respectively). The present study gave an updated epidemiological, clinical and biological profile of infantile VL in Tunisia. The diagnosis delays were considerably shortened compared to previous reports. However, an even earlier diagnosis of cases is needed to improve the disease prognosis. Real-Time PCR showed to be helpful in VL management.

The rapid test OptiMAL-IT® was evaluated in the diagnosis and the screening of imported malaria in Tunisia in comparison with microscopic techniques. This prospective study focused on 500 individuals recruited from September 2010 to September 2012 in laboratory of Parasitology of Pasteur Institute of Tunis. They include 192 patients with clinical manifestations suggestive of malaria and 308 students originating from endemic areas. Microscopy of thick-and-thin blood smears and OptiMAL-IT® test were systematically performed on blood samples of all participants. Sixty individuals revealed infected by Plasmodium (12%). Positivity rates were respectively 20.3% in patients (44 cases) and 5.2% among asymptomatic students (16 cases) (p<0.01). The sensitivity and specificity of the OptiMAL-IT® test were respectively 88.6% and 100%. The concordance kappa was 0.92. The sensitivity and specificity during the screening of asymptomatic subjects were respectively 68.8% and 98.3% with a concordance of 0.67.

Toxoplasmosis when occurring during pregnancy can be transmitted to the fetus and lead to congenital toxoplasmosis (CT). Therefore, pregnant women are a risk group, for which it is necessary to determine the serologic profile. The objective of this study is to determine the serologic profile of toxoplasmosis in pregnant women followed at the Parasitology Laboratory of the Pasteur Institute in Tunis, to establish the prevalence of toxoplasmic infections during pregnancy and the incidence of the CT, noting the difficulties faced in the interpretation of serological results. This is a retrospective study concerning 2833 toxoplasmic serologies practiced on 2070 pregnant women, followed at the Parasitology-Mycology Laboratory of the Pasteur Institute of Tunis, between 2007 and 2010. Serological diagnosis of toxoplasmosis was done by ELISA (Enzyme Linked Immunosorbent Assay) for the detection of Immunoglobulin (Ig) G and M and the study of toxoplasmosis IgG avidity. Prenatal diagnosis was performed for 58 women by amniotic fluid sampling. Toxoplasma gondii was detected by Polymerase Chain Reaction (PCR). At birth, the diagnosis of congenital toxoplasmosis was established based on serology. The toxoplasmic serologies carried out have shown that 45.6% of the pregnant women were formerly immunized while 49.6% had a negative serology. A toxoplasmosis primary infection acquired during pregnancy was detected in 79 cases (3.8%). Among them, 33% had a true seroconversion while 67% had a recent toxoplasmosis infection in view of the positivity of IgG and IgM on the first sample with a low index of avidity (IA). For 21 parturients whose serology showed the presence of IgG, IgM and an intermediate or high IA. Among the 58 parturients in whom prenatal diagnosis was performed, PCR was positive in four cases. After birth, six cases of congenital toxoplasmosis were detected by serology.

The epidemiological situation of leishmaniasis in Tunisia is characterised by the co-existence in a very limited territory (165,000 km2, Sahara included), of 4 clinical forms: the infantile visceral leishmaniasis (VL) and 3 cutaneous leishmaniasis (CL) forms (sporadic, zoonotic and chronic). In addition to the useful epidemiological data, identification of the causative parasitic species is essential to determine the geographic distribution of each form and to select appropriate therapeutic procedure and suitable control measures. 226 Leishmania isolates, 135 human's coming from 59 VL cases and 76 CL cases and 91 canine's were identified by the isoenzyme electrophoresis reference technique. Results confirm the endemicity of the 4 forms mentioned above. The sporadic CL, confined to the North of the country is principally caused by L. infantum MON-24 (72.2%). VL which has reached the southern ridge in the central area of Tunisia, in the governorate of Kairouan (36 typed isolates), presents an unusual high proportion of L. infantum MON-24. In fact, this zymodeme, rather dermotropic is responsible for 47.2% of the cases vs 13% in the other regions of the country where L. infantum MON-1 remains predominant with 78.3% of typed isolates, the difference being statistically significant (P < 0.01). A third zymodeme, L. infantum MON-80 is sporadically pointed out during VL or in sporadic CL. Despite the high number of canine isolates (n=91) coming from 6 governorates, only the zymodeme L. infantum MON-1 was identified, letting hypothetic the reservoir of the 2 other zymodemes of the species identified in humans. Those absences may be related to cross infections, with a low sensitivity to L. infantum MON-24 leading to a selection of MON-1 at the time of culture passages. Hence it is important to develop molecular tools of direct identification on initial biological samples without going through cultures. Zoonotic CL remains the predominant cutaneous form in the central and southern area of Tunisia. However L. killicki, agent of the chronic CL, is confirming its presence out of its original focus of Tataouine in the southern-east of the country in both zoonotic CL and VL areas.

Epidemiological, clinical and parasitological data concerning canine leishmaniasis were collected in two Tunisian populations of dogs, different in breed and life style: 23 rural dogs and 26 dogs of European breeds. All were symptomatic and lived in the north of Tunisia where human visceral and cutaneous leishmaniasis caused by Leishmania infantum are endemic. Leishmaniasis has been confirmed in all dogs by serology or/and by parasitic identification. Significant differences concerning age and symptoms suggest a higher susceptibility to infection in European imported breeds. In fact individuals of this population were significantly younger; 81% were less than 5 years old whereas 57% of the autochthonous rural dogs were more than 5 years old with 31% of them being older than 9 (p = 0.014). In spite of their young age, 75% of imported breeds presented an affection of their general state with more frequent cutaneous symptoms than the rural dogs (96% versus 69%, p = 0.02). Isoenzyme typing of 31 strains, obtained from the two populations, from different sites (blood, lymph nodes, spleen) has only identified the zymodeme Leishmania infantum MON-1. This stresses the need of more investigations to determine reservoirs of the other enzymatic variants identified in humans in Tunisia and Mediterranean basin.

The authors report the presence of Phlebotomus (Larroussius) langeroni Nitzulescu, 1930 in two epidemic foci of cutaneous leishmaniasis due to Leishmania infantum in northwest Tunisia. The Phlebotomus langeroni female is to be mentioned for the first time in North Africa.

Iso-enzymatic characterization of 19 Leishmania strains isolated from Tunisian dogs revealed that all correspond to Leishmania infantum MON-1. This confirms the role of dog as a reservoir of the commonest zymodeme responsible for human visceral leishmaniasis in the Mediterranean basin. However, and in spite of the high number of identifications, many zymodemes, mainly the dermotropic ones as Leishmania infantum MON-24, frequently reported in humans, had never been isolated from dogs. The study of their cultural characteristics may contribute to explain the particular iso-enzymatic profile of dogs strains.

The isoenzymatic typing of 16 stocks of Leishmania, isolated from Tunisian visceral leishmaniasis (VL) cases, revealed that all strains belonged to Leishmania (L.) infantum species. Although zymodeme MON-1 was predictably the most frequent (9 cases), it came as a surprise that L. infantum MON-24 was responsible of about third of cases. This latter zymodeme, while previously reported in Tunisia, Algeria and Spain, was assumed to be a dermotropic and the few cases of VL that it caused occurred always in HIV infected patients. L. infantum MON-80, occasionally reported during both cutaneous and VL of immunocompetent infants was identified in 2 patients. This report confirms that in addition to the more common L. infantum MON-1, zymodeme MON-24 has a substantial role in generating VL in immunocompetent infants in Tunisia.

This study refers to 23 patients presenting with the sporadic forms of cutaneous leishmaniasis encountered in northern most humid parts of Tunisia. Culture inoculation for parasitic isolation was processed using two media: the classical NNN and a rabbit serum based medium (SLC). Cultures were positive in 17 cases with SLC medium and 13 cases with NNN medium. Eight isolates were typed using 15 isoenzymes systems. Six isolates were identified as Leishmania infantum MON-24 which confirms the crucial role of this zymodeme in causing this form of cutaneous leishmaniasis. The other two isolates were identified as Leishmania infantum MON-1, which is the principal agent of visceral leishmaniasis in the Mediterranean area.

The prevalence of intestinal parasitism is generally based on the results of a single stool specimen which probably underestimates the real situation. In order to propose a coefficient for correction, we examined three stool specimens taken from 112 asymptomatic children. Intestinal parasites other than Enterobius vermicularis were detected in 29 subjects (26%). For those specimens that tested positive, 41% of children had infection detected in all three stool specimens; 21%--in two specimens and 38%--in only one. If we assume that the sensitivity of three stool specimen examinations is 100%, then the calculated sensitivity of one examination is equivalent to 68%. This gives an underestimation of the prevalence of 32%. This underestimation is not homogenous for all species. As regards Giardia intestinalis it is 35%, but for other species it would have to be calculated from a larger sample.

A definitive confirmation of the presence in Tunisia of the rare zymodem MON-80 of Leishmania infantum, as a causative agent of infantile visceral leishmaniasis, is reported.

Thanks to the national programme of malaria eradication carried out between 1968 and 1972, there has been no active transmission of the parasitosis in Tunisia since the last indigenous case in 1979. Since 1980, with the increase in international exchanges especially with sub-Saharian countries, only imported cases of malaria have been reported in Tunisia. A retrospective and thorough survey of malaria cases diagnosed in the laboratory of parasitology of the Pasteur Institute in Tunis from 1980 to 1995 determined the epidemiological characteristics of this imported parasitosis. All in all, during the sixteen years following eradication, 245 cases were registered. The majority of cases (86.2%) was diagnosed by a systematic control of groups at risk within the national programme of malaria eradication. The remaining 13.8% cases sought medical advice when clinical symptoms appeared after their return from endemic countries. The population most affected by imported malaria were men (sex-ratio: 6.8) aged between 20 and 40 years (76% of cases); 38% were Tunisians having sojourned in an endemic country, essentially students from sub-Saharian Africa. The presumed country of contamination was African in 92.7% of the cases. Entrance into Tunisia by patients was mainly by air; 4% of the registered cases had come by land from Algeria. Sound knowledge of the epidemiological characteristics of imported malaria would make for a better follow-up of the affected population and thus reduce the probability of repeated transmission.

In order to determine the social and cultural factors which delay hospitalization of children suffering from visceral leishmaniasis (VL), a study was carried out in the rural area of Kairouan (Tunisia). Qualitative techniques were used to investigate beliefs and behaviours associated with the symptoms of VL. The study has demonstrated that the folk interpretation of the disease interferes largely with the choice of the therapy. Regarding VL, the subdivision of the disease into two groups of symptoms, fever and splenomegaly, incites parents to consult doctors in the presence of fever and use traditional healers when splenomegaly appears. This is responsible for long delays before the patients can have access to official health care. This investigation clearly demonstrated that a health education programme is needed in VL endemic areas in Tunisia in order to shorten delays between the appearance of symptoms and their diagnosis. For this objective to be achieved, it would also seem necessary to implement simple serodiagnostic techniques at the periphery level.