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Three clinico-epidemiological forms of cutaneous leishmaniasis (CL) were described in Tunisia: the zoonotic CL (ZCL) epidemic which occurred in the centre of the country caused by Leishmania major MON-25, the chronic CL (CCL) In the south-east of the country caused by Leishmania killicki MON-8 and the sporadic CL In the North (SCL) caused by Leishmania infantum MON-24. The latter form, described in 1991, prevails in northern Tunisia with approximately thirty cases per year. Its vector, unknown for a long time could be according to the last publications, Phlebotomus perfiliewi or Phlebotomus langeroni; however, its reservoir remains unknown until now. The systematic isoenzymatic characterization permits to identify a great number of strains improving then knowledge on the eco-epidemiology of the disease. Indeed, changes were noted in the geographical distribution of these clinical forms: extension of the ZCL to the North and South, extension of the CCL to North and the SCL to the centre. We report in this note the first mention of L. infantum MON-24 in the two provinces of the centre of Tunisia: Kairouan and Sidi Bouzid, confirming the extension of the SCL to the Centre.

The purpose of this study was to evaluate in a retrospective analysis, cases of Mediterranean visceral leishmaniasis (VL) diagnosed in adults during a 20-year period in a department of infectious diseases. Demographic data, clinical and laboratory features and therapeutic findings were considered. During the study period, 22 cases of VL were diagnosed, and 6 (27%) were associated with HIV infection. Fever and splenomegaly were observed in all cases. Anaemia was constant. The anti-leishmanial IF titer was positive among 21 patients (95%). Smears from bone marrow aspiration were positive at microscopy in 95% of cases. Zymodeme analysis was carried out in nine isolates. L. infantum zymodeme MON-1 was characterized in all cases. Seventeen patients (77%) received meglumine antimoniate (MA) (20 mg SbV/kg per day) and 5 (23%) patients amphotericin B (AB) (0.5-1 mg/kg per day) for an average period of 25 days (10-49 days). Adverse events occurred in 7 patients (32%), among them 4 received AB. Clinical cure was achieved with success in 21 patients (95%). After a successful MA treatment of the initial episode, VL relapse was observed in one HIV-positive patient. Only one HIV-positive patient died from neurological disorders. VL is rare in adults. However, its incidence is increasing everywhere in the world, because of HIV-related cases. Its prognosis depends on the precocity of diagnosis and treatment.

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 review the situation on human and canine leishmaniasis observed in Algiers during the period 1990-1997. 1800 sera have been tested by IFAT. The frequency of canine leishmaniasis rises to 37%. 25% of the positive dogs are asymptomatic. The canine leishmaniasis annual fluctuations seem to vary from one year to another, with an increase of number of cases comparing with the last period. Human leishmaniasis is also increasing in Algiers, where 22 cases of HVL and 40 cases CL have been notified. Nine strains of Leishmania (5 from dogs and 4 from human) were isolated and identified by isoenzymes eletrophoresis technique. All stocks were belonging to Leishmania infantum complex. To complete the study, the seasonal dynamic of phlebotomine sandflies was carried out in the same area where 2959 specimens have been captured. The results showed the predominance of P. perniciosus and P. longicuspis, the main vectors of visceral leishmaniasis in Algeria.

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.

In Algeria, visceral leishmaniasis is caused principally by Leishmania infantum MON-1, a common agent of the disease on the edges of the mediterranean basin. Other zymodemes (MON-34 and MON-80) of the same complex have also been isolated from immunologically competent patients. In the present study, the authors report the presence of Leishmania infantum MON-24, the main agent of cutaneous leishmaniasis in northern Algeria, in five children with visceral leishmaniasis.

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 authors report the first documented observation of infantile visceral leishmaniasis due to Leishmania infantum MON-24 zymodeme in Tunisia. This zymodeme was isolated from a non-immunodepressed two-year-old child, with visceral leishmaniasis, originating from Zaghouan, in northern Tunisia. This case shows that beside L. infantum MON-1 and MON-80, L. infantum MON-24, the usual parasite of cutaneous leishmaniasis, there exists also a causative agent of visceral leishmaniasis in our country.