Kala-azar in Portugal. V. The sylvatic cycle in the enzootic endemic focus of Arrabida.

Leishmania parasites were found in three of 43 foxes examined in the Arrabida region of the Setúbal peninsula in Portugal, this brings the total number of cases of vulpine leishmaniasis to four in 71 animals examined in this area, a prevalence rate of 5.63%. The three parasitized foxes found in this study were all symptomless and NNN cultures inoculated with tissue extracts were positive for all three animals. The immunofluorescence antibody test (IFAT) was positive with titres greater than or equal to 1/128 in the three infected foxes. The isoenzyme electrophoretic profile obtained from these positive cultures showed the strains to be identical with others isolated in Portugal from man, dog and fox, as well as with strains from elsewhere in the Mediterranean (zymodeme 1). The prevalence rate of 5.63% is probably sufficient to maintain endemicity. The presence of a semi-autonomic sylvatic cycle in the area seems likely. Hepatozoon was found in 28 foxes (65.11%).