Incidence and Time Course of Leishmania infantum Infections Examined by Parasitological, Serologic, and Nested-PCR Techniques in a Cohort of Naïve Dogs Exposed to Three Consecutive Transmission Seasons

摘要: Most experience in the comparison of diagnostic tools for canine leishmaniasis comes from cross-sectional surveys dogs different ages and breeds cases with unknown onset duration leishmaniasis. A longitudinal study was performed on 43 beagle exposed to three transmission seasons (2002 2004) Mediterranean examined periodically over 32 months through bone marrow microscopy nested PCR (n-PCR), lymph node culture, serology (immunofluorescent-antibody test), evaluation clinical parameters. Starting January 2003, highest rate positives detected by n-PCR at all assessments (from 23.3% 97.3%). Sensitivities serologic parasitological techniques were lower but increased time, 15.8% 75.0 77.8%. Some that tested positive negative other tests (“subpatent infection”) remained so until end or converted subsequent assessments, whereas and/or microscopy/culture (“asymptomatic patent exhibited progressive leishmaniasis; 68% them developed disease (“symptomatic during study, 7 (range, 3 14) after being tests. Postexposure infection incidences high significantly between 2002 2003 exposures (39.5% 91.7%, respectively). The time course highly variable each dog, patterns identified: (i) rapid establishment a condition (0 2 detection infection); (ii) prolonged subpatent (4 22 months) before progression; (iii) transient followed 10 21 apparent Leishmania-negative status progression.