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Leishmania (L.) infantum strains, isolated from varying hosts and clinical manifestations (cutaneous, visceral and canine leishmaniasis), were investigated in order to understand the genetic polymorphisms within this species in Algeria and Tunisia. Two DNA‐based typing methods were tested in order to evaluate their effectiveness against Multilocus enzyme electrophoresis (MLEE), widely considered as the reference method for Leishmania parasite typing. On the other hand, MLEE is cumbersome, high‐cost, time consuming and frequently does not detect intra‐species genetic polymorphisms. In this work, we used two molecular target regions to discriminate L. infantum strains, Internal transcribed spacer 1 (ITS1) and the cysteine proteinase B (cpb). The ITS1 region offers good resolution for Leishmania discrimination but does not spotlight intra‐species polymorphisms. In contrast, cpbE and cpbF PCR‐Sequencing demonstrated a certain variability within CL and VL Algerian and Tunisian L. infantum isolates. Following phylogenetic analyses of 44 L. infantum isolates, two main groups were identified, a group with 39 bp deletion in the cpb sequence, composed of cutaneous, visceral and canine isolates from both countries with no significant clinical or geographic distribution; these samples were typed as MON‐1, MON‐24, and MON‐80 zymodemes. A second group which presents a clear clusterization of Tunisian cutaneous strains belonging to the L. infantum MON‐24. This group, with no deletion in the mature domain of the cpb gene sequence, should be further explored with a higher number of samples. [ABSTRACT FROM AUTHOR]

Abstract Background The present study was conducted to investigate the serological survey of Toxoplasma antibodies in local.horses from three major regions: a neighbourhood of a city in the North (Sidi Thabet), a neighbourhood of a city on the coast (Monastir) and a neighbourhood of a city in the middle (Battan) of Tunisia (North of Africa). Methods A total of 158 serum samples were obtained from clinically healthy horses which consisted of 111 (32 female, 79 male) 2-10 years old and 47 (11 female, 36 male) older than 10 years. All of the horses were tested for antibodies to T. gondii using the Modified Agglutination Test (MAT). Results According to MAT results, antibodies to T. gondii were found in 28 (17.7%) of 158 sera with the titers of 1:20 in 20 horses, 1:40 in 1 horse, 1:80 in 2 horses, 1:160 in 2 horses, 1:320 in 1 horse and ≥1:640 in 2 horses. Anti-T. gondii antibodies were found in 18 (16.2%) of 111 horses (2-10 years old) and 10 (21.2%) of 47 horses (older than 10 years old). Six (13.9%) out of 43 female had anti-toxoplasma antibodies and 22 (19.1%) from 115 males remained positive. Conclusion Statistically significant differences in age groups and genders were observed between the seropositive and seronegative horses using the Chi square X(2) test. Other statistical correlation was also reported concerning horse breed.

Abstract Background Clinical manifestation due to infection by Toxoplasma gondii is closely linked to the infecting strain of the parasite. Several genetic markers are available to determinate its genotype but few of them are able to discriminate between the three predominant lineages, namely types I, II and III. The number of markers decreases when atypical, recombinant/mixed genotypes need to be identified. Findings In our study, the contribution of sequence polymorphisms in the AK69 gene as typing markers for T. gondii was investigated for the first time in an epidemiological study. The coding region of the marker was amplified, sequenced and aligned for different Toxoplasma strains. The identified nucleotide polymorphism at 12 positions was able to highly discriminate between the different congenital toxoplasmosis Tunisian strains. Moreover the high detection sensitivity level of the marker enabled unambiguous identification of mixed/recombinant genotypes directly. Conclusion It can be, thus, very useful for direct typing in areas where such genotypes are frequently encountered, mainly in the African continent.

Toxoplasmosis has been recognized as parasitic zoonosis with the highest human incidence. The human infection by the parasite can lead to severe clinical manifestations in congenital toxoplasmosis and immunocompromised patients. Contamination occurs mainly by foodborne ways especially consumption of raw or undercooked meat. In contrast to other foodborne infections, toxoplasmosis is a chronic infection which would make its economic and social impact much higher than even previously anticipated. Ovine meat was advanced as a major risk factor, so we investigated its parasite survey, under natural conditions. Serological MAT technique and touchdown PCR approaches were used for prevalence determination of the parasite in slaughtered sheep intended to human consumption in Tunis City. The genotyping was carried by SNPs analysis of SAG3 marker. Anti-Toxoplasma antibodies were present in 38.2% of young sheep and in 73.6% of adult sheep. Molecular detection revealed the contamination of 50% of ewes’ tissue. Sequencing and SNPs analysis enabled unambiguous typing of meat isolates and revealed the presence of mixed strains as those previously identified from clinical samples in the same area. Our findings conclude that slaughtered sheep are highly infected, suggesting them as a major risk factor of Toxoplasma gondii transmission by meat consumption. Special aware should target consequently this factor when recommendations have to be established by the health care commanders. [ABSTRACT FROM AUTHOR]

Introduction: travellers to endemic areas must know malaria, its risk factors and prophylactic measures. This can help to avoid severe cases of malaria and to prevent transmission in countries that are malaria-free. The purpose of this study is to assess Tunisian travellers´ knowledge about malaria, its transmission and prevention and their adherence to prophylactic measures., Methods: we conducted a survey based on two anonymous questionnaires (pre- and post-trip) among adults travelling to endemic countries. The 1st questionnaire was followed by a medical interview focusing on level of risk and recommended prophylactic measures., Results: two hundred and eighty-nine travellers were recruited. They mainly moved within sub-Saharan Africa (99%) for professional reasons (84,4%). The average age of subjects was 42.3 years and sex ratio (male/female) was 3.1. Prior to departure, only 53.3% of subjects were aware of the risk of malaria, and only 28% gave correct answers about modes of transmission. Recommendations for chemoprophylaxis were only known by 62.3% of subjects and only 43.6% intended to use chemoprophylaxis (p < 0.01). Better adherence to protective measures, including chemoprophylaxis, was reported after the trip, with attitudes qualified as good or excellent by 64.2% on return against 23.7% before the interview (<0.001)., Conclusion: Tunisian travellers knowledge of malaria is insufficient. Strengthening information through specialized consultations (whose usefulness has been demonstrated) is required., Competing Interests: Les auteurs ne déclarent aucun conflit d´intérêts., (Copyright: Sonia Kechaou-Cherif et al.)

Visceral leishmaniasis (VL) is a severe life threatening parasitosis requiring early management of cases. It is an emerging disease in the Mediterranean region with a spread of endemic areas and an increase in case incidence. The patient profile has also evolved with more affected adults, presenting generally non-specific symptoms. Hence the interest of a systematic biological confirmation. The microscopic detection of Leishmania amastigotes in bone marrow aspirates (BMA) smears is the gold standard diagnostic technique. However, it requires invasive sampling. Serological tests searching for specific antibodies remain highly contributory, but their interpretation must always take into account the epidemiological context and the patient's clinical and biological features. Currently, the Western-Blot represents the most specific serological technique for diagnostic confirmation. VL diagnosis has greatly improved by the introduction of both rapid diagnostic tests (RDTs) and molecular biological techniques. RDTs using recombinant rk39 antigen are easy to perform and deliver results in less than 30 minutes. Real-time PCR (Polymerase Chain Reaction) is currently retained as the best technique for VL diagnosis. It is efficient on simple blood samples, allowing to avoid invasive BMA needed for microscopy. In addition, real time PCR estimates parasite load which is helpful for the post-treatment follow-up. In any case, the choice of techniques to be used should be strategic and adapted to the local epidemiology as well as to the means available.

In spite of its elimination from Tunisia, malaria remains a public health concern due to the severity of the disease and risk of its reintroduction. The vulnerability of our country is related to the persistent anophelism and to the existence of a potential reservoir represented by imported cases. In the absence of a stay in an endemic area, the suspicion of malaria remains a rare event. However, in front of the possibility of other modes of contamination, this parasitosis must be evoked in any fever without obvious etiology. Especially as delayed diagnosis in non immune subjects may cause a severe illness and death. We propose to present the principal clinical and biological aspects of malaria and to specify the action to be taken when the infection is contracted outside a stay in endemic areas, in order to determine the origin of contamination.

Background: In Tunisia, detection of Plasmodium in asymptomatic individuals from endemic countries is a critical measure in national program of malaria eradication. The screening is based on microscopic examination of thick and thin blood smears. However, the performance of this diagnosis is closely related to the experience of biologist and the parasitaemia., Aim: The objective of this study was to evaluate the contribution of the PCR in the screening of malaria., Methods: This prospective study involved 260 students from malaria endemic areas who were screened for malaria between september 2011 and june 2013. Each subject had a blood sample which was examined for malaria by microscopy and nested multiplex PCR., Results: PCR detected the presence of Plasmodium in 13 blood samples (5%). While microscopy was positive only in nine cases (3.5%). The discordances involved five negative samples at microscopy and which were positive in PCR and a negative sample in PCR which was positive at microscopy. A mixed infection with Plasmodium falciparum and Plasmodium malariae was identified by PCR. For this case, microscopy diagnosed only Plasmodium falciparum specie., Conclusion: PCR is more efficient than microscopy in detecting low parasitaemia ; particularly observed in asymptomatic subjects. This technique allows to reduce asymptomatic carriage of Plasmodium and reduce the risk of a resumption of transmission of malaria in our country.

Background: The prevalence of intestinal parasitosis is very different according to countries. Therefore, it is always interesting to update the data in Tunisia to better direct control measures., Aim: The objectives of this survey were to estimate the prevalence of intestinal parasitosis in the region of Tunis, to study their evolution and to establish various combinations of intestinal protozoa., Methods: This is a retrospective study carried out over a period of 17 years from 1996 at 2012 and which involved 20033 individuals. Each subject had one or more stool examination which included a direct microscopic examination and a concentration by modified Ritchie technique., Results: The prevalence of intestinal parasitosis was 12.55%. Entamoeba histolytica/dispar and Giardia intestinalis accounted respectively a prevalence of 0.51% and 1.48%. Hymenolepis nana was the most predominant helminth with a prevalence rate of 0.53%, followed by Enterobius vermicularis (0.21%). Two cases of Hookworms and seven cases of Strongyloides stercoralis were diagnosed. Polyparasitism concerned 16.59% of infected individuals. Significant combinations occured mainly for amoeba in particular Entamoeba histolytica/dispar and Entamoeba coli (r=0.232)., Conclusion: Our study confirms the decrease of the prevalence of giardiasis and amebiasis, whereas helminthiases with direct transmission remain frequent.

We report the first case of an imported Plasmodium ovale relapse in a Tunisian man who developed malaria three years after leaving sub- Saharan Africa. A 29-year-old Tunisian man consulted in September 2011 because of a fever, myalgia, and headache that had begun eight days earlier and persisted despite treatment with oral antibiotics. On questioning, the patient stated that he had resided three years ago for six months in Ivory Coast, where he acquired malaria. He was treated with artemether-lumefantrine. The patient said he had no recent travel to any other malaria-endemic area and had not received a blood transfusion. A first microscopy of peripheral blood smears was negative for malaria parasites. The diagnosis was established 17 days after onset of symptoms. A repeat microscopic examination of blood smears confirmed the presence of Plasmodium ovale with a parasitemia lower than 0.1%. The patient was treated with artemether lumefantrine, followed by primaquine. This case emphasizes the possibility of relapse of some plasmodial species. It highlights the importance of repeating microscopic examination of blood when the diagnosis of malaria is suspected.

We report the identification and typing of a congenital toxoplasmosis case in a diabetic pregnant young woman living in Tunis. The Toxoplasma DNA extracted from amniotic fluid was detected by Real Time PCR and subjected to a multilocus genetic characterisation of the strain at markers: 3'SAG2, 5'SAG2, New SAG2, SAG3, GRA6, BTUB, APICO, PK1, KT850 and UPRT1. An atypical genotype of T.gondii with unusual genetic composition was revealed. It is the first time that an atypical strain has been associated with congenital toxoplasmosis in Africa. Atypical strains are associated with severe clinical manifestations so systematic genotyping should be investigated with the amniocentesis.

Background: The detection of antibodies in saliva samples proved to be effective in the diagnosis of several microbial diseases. These antibodies were screened in saliva samples of patients with hydatid cysts., Methods: Anti-hydatid fluid antigen IgG and IgA antibodies were screened in saliva and sera of patients with hydatid cysts (n=37) as well as in healthy controls (n=30) using an in-house developed immunoenzymatic assay., Results: Salivary anti-hydatid fluid antigen IgG showed a sensitivity of 86.5% and a specificity of 80%. A positive correlation was observed between anti-hydatid fluid antigen IgG in saliva and in serum (r = 0.364; p = 0.02)., Conclusions: The detection of anti-hydatid fluid antigen IgG antibodies in saliva using ELISA promises to be interesting for the diagnosis of cystic echinococcosis.

Forty-two patients with visceral leishmaniasis in Tunisia were treated with meglumine antimoniate and followed-up for clinical improvement and blood parasite load determined by quantitative real-time polymerase chain reaction (PCR). Parasite loads before treatment ranged from 27 to 5.3 x 10(7) parasites/mL. At the end of treatment, parasite load decreased significantly in 39 cured patients (P < 0.001). The decrease in parasite load after treatment was greater than 99% for 34 patients and PCR results became negative in 23 of them. Two patients without clinical improvement showed no or slight decreases in parasite load (209 versus 202 parasites/mL and 1,765 versus 146 parasites/mL). One patient showed had a relapse seven months after showing a good response to treatment. His parasitemia remained high despite a sharp decrease (5.2 x 10(5) versus 5.9 x 10(3) parasites/mL).

A case of a tinea capitis caused by Trichophyton schoenleinii is presented. It involves a 6-year old Tunisian boy that had presented with diffuse scaling of the scalp misdiagnosed as psoriasis and was treated unsuccessfully with keratolytic shampoos for two years. Tinea favosa due to Trichophyton schoenleinii was confirmed by mycological examination. He was successfully treated with griseofulvin for 6 weeks and topical application of imidazole. Trichophyton schoenleinii is an important anthropophilic dermatophyte that causes tinea favosa. It is transmitted by contagion between humans and is currently endemic in Africa. Ringworm is still frequent in Tunisia, but favus is becoming exceptional due to improvements in living conditions and hygiene.