[Seroprevalence of Leptospira infection in habitants of peripheral neighborhoods in Cali, Colombia].

Introduction: Leptospirosis is a zoonotic disease with varying modes of transmission and clinical expression that affects humans inhabiting urban and rural areas worldwide. In Colombia, little is known regarding leptospirosis in urban settings.

Objectives: To establish the seroprevalence of leptospiral infection in humans, to assess the serological reactivity and to identify factors associated with seropositivity.

Evidence for leishmania (viannia) parasites in the skin and blood of patients before and after treatment.

Background: American cutaneous leishmaniasis is considered to be a zoonotic disease transmitted by sand flies that feed on infected sylvatic mammals. However, the "domestication" of transmission and the increase in treatment failure with antimonial drugs have raised the suspicion of anthroponotic transmission of American cutaneous leishmaniasis.

Methods: The objective of the present study was to explore the potential of humans as a source of infection for sand flies.

Pathogenicity and protective immunogenicity of cysteine proteinase-deficient mutants of Leishmania mexicana in non-murine models.

This study demonstrates that deletion of cysteine proteinase (CP) genes diminishes pathogenicity of Leishmania mexicana in non-murine experimental host models while preserving immunogenicity. Both cpb and cpa/cpb-deficient lines induced delayed disease onset, smaller lesions and lower parasite burden in hamsters. cpa/cpb-deficient L.