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Leishmaniosis is reported in the Iberian Peninsula and the Balearic Islands, but the Canary Islands are deemed free. In the present communication, we report a clinical leishmaniosis due to Leishmania infantum in a dog that was presumptively infected during its stay on Tenerife. The result of Leishmania serology (whole-cell based ELISA with L. infantum antigen) was high positive (test score of 82.2 at a cut-off value of 12.0). This result was further confirmed with quantitative real-time polymerase chain reaction (qPCR) for Leishmania spp. on a blood sample. A medium load of parasites was detected (48 parasites/ml blood). L. infantum was identified by RFLP analysis of the ITS-1 PCR product. Confirmation that leishmaniosis is endemic to the Canary Islands would further require study on local dogs with no travel history as well as reassessment on frequency and distribution of Phlebotomus spp. as well as Leishmania spp. detection in the sand fly vector. However, this case strongly suggests that L. infantum is present on the Canary Islands. Although transmission seems to be still exceptional, preventive measures in dogs travelling to the Canaries should be considered. [ABSTRACT FROM AUTHOR]

Interferon-τ (IFN-τ) treatment of Trichinella spiralis-infected BALB/c mice was investigated. The therapeutic regimen consisted of daily intraperitoneal injection of 10 U murine IFN-τ for 7 days, starting at 2 weeks post-infection. Striated muscle samples (diaphragm, thigh) were collected at 4, 8 and 12 weeks after infection. The muscle larval burden, the degree of encystation and the digestion of T. spiralis larvae were investigated. Furthermore, immunohistochemical studies of the inflammatory cell infiltrate around encysted larvae were performed. The results demonstrated an influence of IFN-τ treatment on the CD4 and CD8 subset distribution during the immune response but revealed no difference in the degree of encystation or digestion of encapsulated larvae as compared with control values. [ABSTRACT FROM AUTHOR]

Mucosal leishmaniasis is a well-known clinical manifestation of infections caused by species belonging to the Leishmania (Viannia) subgenus in Central and South America but not of Leishmania species endemic in the so-called Old World. We report on three cases of mucosal leishmaniasis caused by Leishmania (Leishmania) infantum contracted in southern Europe. Two patients were immunocompromised; one patient had no underlying condition. Lesions were located in the oral mucosa, oesophagus and nose. All lesions relapsed under standard treatment with liposomal amphotericin B. A cure was achieved after secondary and extended treatment with liposomal amphotericin B or miltefosine. Mucosal leishmaniasis contracted in southern Europe has to be considered in the differential diagnosis of lesions in the naso-buccal-oesophageal mucosa and may occur in previously healthy persons.

Tungiasis is caused by the penetration of the female sand flea Tunga penetrans into the skin of its host. This parasitic skin disease is almost invariably associated with an intense inflammation around embedded fleas, the underlying mechanisms being unknown. A study was undertaken to determine whether Wistar rats can be used as an animal model to assess cytokine kinetics during the natural course of the infection. Laboratory-raised Wistar rats were exposed in cages put on the soil in an area with high human attack rates. Rats were examined daily and blood samples were taken before exposure and at 2, 6, 10, 13, 16 and 20 days after flea penetration. TNF-alpha, IL-1 beta, IFN-gamma, IL-4, IL-10 and CINC (a rat cytokine- induced neutrophil chemoattractant and member of the IL-8 family) were determined by enzyme immunoassay. The results showed an increasing serum concentration of TNF-alpha and IL-1 beta 10-13 days after penetration and a rapid increase in IL-4 2 days after fleas became embedded. During the natural course of the infection, the ratio of the serum concentration of TNF-alpha to that of IL-10 decreased, indicating a relative increase in the secretion of the anti-inflammatory cytokine. The treatment of lesions with silicone oil abrogated the natural disease course and changed the pattern of cytokine secretion. We conclude that the Wistar rat is an appropriate model to study immune responses in tungiasis.

The immunochromatographic test (ICT) for the rapid diagnosis of malaria has been marketed for several years. In a study in which three Centres of Tropical Medicine participated and data were pooled, performance of the test varied considerably when comparing the results between each centre. The sensitivity of ICT in 2,343 patients tested in our services was 100% and the specificity 99.74%. Moreover, two patients with a positive ICT would initially have been missed by expert microscopy, with Plasmodium falciparum malaria being confirmed microscopically some hours later. The principal reasons for the better performance of the test in our series appear to be blood collection in EDTA vials and considerable experience with handling and interpreting the ICT test.

Tungiasis is caused by penetration of the female jigger flea, Tunga penetrans, into the skin of its host. This parasitic skin disease is almost invariably associated with intense inflammation around embedded fleas, the underlying mechanisms being unknown. A study was undertaken to determine whether the inflammatory process can be attributed to immune activation induced by a biologically active foreign body. We determined the concentrations of Th1-mediated (IFN-gamma, TNF-alpha) and Th2-mediated (IL-4) cytokines in the sera of patients with tungiasis. The results were compared with those of controls infected with different helminths or exposed to soil-transmitted helminths. The results show that tungiasis causes a mixed Th1 and Th2 immune response, characterized by significantly increased concentrations of the pro-inflammatory cytokines IFN-gamma and TNF-alpha, with a slightly increased concentration of IL-4. The preponderance of the Th1 immune response was indicated by a significantly increased TNF-alpha/IL-4 ratio in patients with tungiasis, as compared with the control groups.