Leptospirosis survey in wild rodents living in urban areas of Rome.

The aim of the study was to survey the current extension of the infected brown rats (Rattus norvegicus) living on the site Ripa Grande-San Michele port located in the center of the sity along the accessible right bank of the Tiber river by using a specific molecular technology. The detection of Leptospira, in 11 trapped brown rats, by tube-based Polymerase Chain Reaction (PCR) was performed. The amplified samples were analysed by capillary zone electrophoresis (CZE). Sequence analysis of the amplified DNAs confirmed the specificity of the detection of leptospires. Five out of 11 brown rats exhibited positivity for Leptospira. The survey points out the high rate of leptospiral infection in the brown rats living in the most ancient urban area of Rome.

Molecular identification of Borrelia valaisiana and HGE-like Ehrlichia in Ixodes ricinus ticks sampled in north-eastern Italy: first report in Veneto region.

PCR amplification was applied to screen the presence of both Borrelia burgdorferi s.l. and Ehrlichia species in pools of field-collected Ixodes ricinus ticks. The specimens so far analysed (n = 55), grouped in 11 pools, were sampled in Feltre area (Veneto region, NE Italy). Five pools proved positive for B. valaisiana (45%) and one of them (9%) was also positive for Ehrlichia, that was further characterised as a HGE-like Ehrlichia. This is the first report of the two bacteria in the Veneto region. The pool positive for both pathogens was used to adjust a multiplex PCR assay, which allowed the detection and identification of both parasites in a single experiment. The advantages offered by this assay, when standardised, will substantially broaden the perspectives of ecological and epidemiological investigations on animal/human Lyme disease and ehrlichiosis, greatly facilitating disease surveillance and control programs.

HPLC does not differentiate Mycobacterium paratuberculosis from Mycobacterium avium.

HPLC, which is gaining its place as identification tool in mycobacteriology laboratories, has been proposed to distinguish Mycobacterium paratuberculosis from Mycobacterium avium. We had reported no significant difference between M. avium and M. paratuberculosis reference strain ATCC 19698. Because of the advantages offered by such a method, we enlarged our observations to include more isolates of M. paratuberculosis. Within the double cluster of peaks obtained by both M. avium and M. paratuberculosis, we could not find a consistent difference typical of M. paratuberculosis. Therefore, the present study confirmed that M. avium and M. paratuberculosis could not be distinguished by HPLC, raising doubts of a straightforward use of HPLC to identify M. paratuberculosis.

Ehrlichia infection in Italy.

Immunoglobulin M seroconversion to Ehrlichia chaffeensis was documented in U.S. citizens bitten by ticks in Sardinia. Seven cases of suspected ehrlichiosis in local residents were not confirmed by laboratory tests. In Alpine areas antibodies to E. phagocytophila were detected in persons at high risk, i.e., foresters (8.6%) and hunters (5.5%), and in controls (1.5%). Of 153 persons bitten by ticks, only one was Ehrlichia antibody-positive after 6 months.

Infections in an Alpine environment: antibodies to hantaviruses, leptospira, rickettsiae, and Borrelia burgdorferi in defined Italian populations.

From 1987 to 1991, a seroepidemiologic survey for antibodies to hantaviruses, leptospira, rickettsiae, and Borrelia was conducted in selected Italian population groups. In the mountainous areas of northeastern Italy, the prevalence of antibody to hantaviruses, as detected by indirect immunofluorescent antibody (IFA) assay, was 7.1%, 4.8%, 4.3%, and 4% in 265 forestry workers, 82 rangers, 395 farmers, and 75 hunters, respectively. Among 299 Alpine soldiers, the prevalence was lower (0.7%). Of those with Hantaan antibody, the reactivity pattern using Hantaan, Puumala, and Fojnica viruses suggested a prevalence of antibody to Hantaan virus, with titers reaching levels of 128. The presence of leptospiral antibodies (by microagglutination test), which included the prevalence of antibodies to Leptospira icterohaemorrhagiae, L. bratislava, and L. saxkoening serotypes, was observed in 10-12% of the farmers and forestry workers in these Alpine mountain regions. Only a few sporadic clinical cases of leptospirosis have been reported from these regions. Antibodies to Borrelia burgdorferi (by IFA) were observed in 19% of the rangers and forestry workers, with lower values in farmers (10%) and hunters (8%). These data suggest the presence of a large number of asymptomatic infections with B. burgdorferi and the leptospires in the densely wooded areas of the Alpine Italian regions. Furthermore, the recent identification of a case of Hantaan acute nephropathy in a man living in the mountainous northeastern area of Italy confirms the presence of hantavirus in the Italian Alpine zones, especially those near the Slovenian border.

Fractionation and characterization of hydatid fluid antigens with identification of an antigen similar to human serum albumin.

Human and sheep hydatid fluids were separated by ultrafiltration, gel chromatography and immunoabsorption into several immunogenic fractions in which both parasite antigens and host substances were present. The immunological characterization of proteic antigens was carried out by immunodiffusion and immunoelectrophoresis with rabbit and ram antisera. A line of identity was observed between a human fraction (labelled as III) and a sheep fraction (labelled as 2B). Further evidence of the presence of a parasitic antigen in fraction III was given by its reaction against an antiserum from ram directed against sheep fraction 2B. The immunological characterization of fraction III indicated a close similarity between human serum albumin and parasitic antigens.