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Recent investigations on the distribution of human and canine leishmaniasis, and on the vectors and wild reservoirs of the disease in foci in Tuscany have stimulated a retrospective evaluation of human leishmaniasis of the whole region. From a study of the literature, of statistical reports (ISTAT) and of unpublished information, 77 cases of visceral leishmaniasis and 97 of cutaneous leishmaniasis have been analysed. From the case reports of both forms it appears that: (a) a higher incidence of cases occurred in restricted areas; (b) visceral and cutaneous leishmaniasis have been hypoendemic in Tuscany since the years of the earlier reports (1933 and 1936, respectively); (c) the number of infantile visceral cases was much higher in the period from 1933 to 1955 (84.5% of subjects in the 0-10 years age group) than in the subsequent years, 1956-75 (50.0%). The possible significance of the infantile and adult forms of visceral leishmaniasis in Tuscany is discussed, and the local data are compared with those of other regions.

A survey of phlebotomines has been made in the area of the Province of Grosseto (Tuscany, Italy) where human cases of both visceral and cutaneous leishmaniasis have recently occurred. 12 collecting stations, placed around the leishmaniasis foci, were divided into three groups of localities, the Argentario Promontory, coastal plains territory and hilly inland territory. Sandflies were collected with lit and unlit oil traps, and by hand. A total of 11,032 specimens (57% males) were caught and identified. Of these, 86.6% were Phlebotomus perfiliewi, 10.8% P. perniciosus and 2.3% Sergentomyia minuta; only a few specimens were P. papatasi and P. mascittii. In the first group of localities, P. perniciosus was very abundant (87.8%) and S. minuta scarce (12.0%); in the second group, P. perfiliewi was the only species collected; in the third group, P. perfiliewi was very abundant (98.0%), S. minuta was vert scarce (1.1%) and P. perniciosus even more so (0.7%). P. perniciosus is thought to be the probable vector of visceral leishmaniasis in the area of the Monte Argentario and P. perfiliewi is strongly suspected of playing a role in transmission of the cutaneous form in the third group of localities. The species responsible for transmitting visceral leishmaniasis in some of the foci in this area is yet to be found.

Two promastigote-infected specimens of Phlebotomus perniciosus Newstead, 1911, were found in the province of Cagliari, Italy. The parasites from one specimen were successfully cultured in a hamster. The isolate was typed on 11 enzymes and shown to be identical with the reference strain of Leishmania infantum s.st. This is the first typing of a leishmanial organism from naturally infected P. perniciosus.

From April 1977 to February 1978, wild mammals were trapped in a focus of low leishmanial endemicity (Baccinello) in the Province of Grosseto (Tuscany, Italy). Spleen homogenates of the trapped animals were injected i.p. into hamsters, from which spleen biopsies were taken after 60 days and impression smears carefully observed for the presence of Leishmania. Positive spleens were subinoculated into hamsters. 404 animals of 12 species were trapped: 31 insectivores, 317 rodents and 56 carnivores. Black rats (Rattus rattus) and field mice (Apodemus sylvaticus) were the rodent species most frequently trapped--160 and 139 respectively--of which 143 and 134 respectively were tested in hamsters for Leishmania. 35 foxes (Vulpes vulpes) were caught, of which 16 were tested for Leishmania. Four hamsters were found infested with Leishmania. Three of them had been injected with spleen homogenates from R. rattus and one from V. vulpes although liver and spleen impression smears of all trapped animals were negative for Leishmania on direct microscopical examination. The significance of Leishmania infection in wild animals in the leishmanial focus of Baccinello is discussed.

Soil analysis was carried out on samples obtained from a breeding-site of the sandflies Phlebotomus perniciosus Newstead, P. perfiliewi perfiliewi Parrot and Sergentomyia minuta (Rondani) in Sardinia. Soil texture, pH, CaCo3, organic matter and water content showed no correlation with the number of sandflies that emerged from the places where soil samples were taken. It appears that pre-imaginal stages of these phlebotomine sandflies are associated with a relatively stable, cool and humid environment protected from sunshine and rain, rich in clay and in organic nitrogen.

Enzyme typing by starch gel electrophoretic techniques was carried out on 11 Leishmania isolates from Italy in laboratories in Montpellier and London. The enzymes studied in the former were ME, G-6-PD, 6-PGD, PGM, PGI, GOT (= ASAT), MDH and IDH. In London slightly different procedures were used to examine ME, 6-PGD, PGM, PGI and ASAT. In addition, SOD, ALAT, NH, and MPI were studied. The combined data revealed that four Rattus rattus and four dogs were infected with classical L. infantum (zymodème 1). In addition, two other dogs and a fox were infected with an enzyme variant (zymodème 18) which differed in four of the 12 enzymes examined. These findings raise the question of the heterogeneity of the parasites causing visceral leishmaniasis.

A skin test survey carried out in the towns of Porto St. Stefano and Porto Ercole showed a total positivity rate of 15.3%. The progressive increase of positivity according to age was not uniform but similar for the two towns since the values concerning the last two age groups did not follow the general trend of the graph but were lower than expected. The possible causes of this phenomenon have been discussed. The absence of overt visceral leishmaniasis cases in recent years and the concomitant high prevalence of canine leishmaniasis have been considered in the light of the occurrence of infectious diseases and the increase of the nutritional levels in the local human population.

An entomological survey carried out in 1985 in the zoonotic cutaneous leishmaniasis foci of the Center of Tunisia (Sidi Bouzid Governorate), showed the presence of 7 phlebotomine species. Phlebotomus (P) papatasi, the most abundant species (84.6%), was essentially trapped in rodent burrows. Its anthropophily was demonstrated by man-baiting catch. The highest population density was observed during July and August, for P. papatasi. Its role in the transmission of Z. C. L. in Tunisia is discussed. P. perniciosus, less abundant (13.2%) was mostly trapped in animal resting places. Only few specimens of P. longieuspis, P. perfiliewi, Sergentomyia (S) minuta, S. antennata and S. dreyfussi were observed.

The results of a survey of canine leishmaniasis in the coastal focus of Monte Argentario (Tuscany, Italy) are reported. Of the 171 dogs examined, 41 (23.9%) were positive in the fluorescent antibody test (FAT), but only 12 (7.0%) were positive by microscopic observation of lymphatic ganglia. Of the 41 FAT positive dogs, 17 (10.0%) showed signs of the disease. The evolution of leishmaniasis over one year from the first examination showed that 88.0% of the dogs with signs died of the disease, and 36.0% of the asymptomatic dogs became patent or died; 52.0% of the asymptomatic dogs had apparently recovered. The prevalence of the disease, the geographical, age, sex and race distribution of cases, the evolution of leishmaniasis in dogs and FAT positivity are discussed.

During the summer-autumn period of 1983 and 1984, 1408 specimens of Phlebotomus perniciosus, 74 of P. perfiliewi perfiliewi and 35 of Sergentomyia minuta were caught in emergence traps in a locality close to the village of Soleminis, a canine leishmaniasis focus 15 km from Cagliari, Sardinia. All the flies were collected from a breeding site inside an abandoned cement building. Male flies were highly predominant for all three species. A few larvae of P. perniciosus were also collected from the same site. This is the first finding of an abundant larval breeding site of P. perniciosus.

Leishmanin skin testing was performed on 1,285 people in the Tuscany region of Italy. In a known endemic area for leishmaniasis there was an increasing positivity with age, while in another area the curve was bell-shaped suggesting an interruption of transmission in the recent past. In all areas the positivity rate for males was higher than for females, but it was not possible to distinguish between areas of cutaneous and visceral disease.

Preliminary data on a project planned in Sardinia for the epidemiological study of leishmaniases are presented. Twenty-six dogs were found infected in the south-western part of the island. Nine isolates were successfully stabilated . In a canine leishmaniasis focus on the outskirts of Cagliari, Phlebotomus perniciosus was the predominant sandfly species (95%). In the same area, 28 specimens of Rattus norvegicus were trapped and their spleen homogenate was injected into hamsters. No Leishmania has yet been isolated.