Bovine tuberculosis in Ethiopian wildlife.

Bovine tuberculosis (BTB) is endemic in Ethiopian cattle. However, the status of the disease in wildlife populations that often share habitat with livestock is unknown. We screened for BTB in wildlife in five regions in Ethiopia. Blood and tissue samples from 133 mammals of 28 species were collected from 2006 to 2008. We used a rapid serology test (RT) based on lateral flow technology, and performed culture of lymph node specimens inoculated onto Lowenstein-Jensen and Middlebrook 7H11 media. Acid-fast colonies were further analyzed by molecular typing. Sera from 20 of 87 animals (23%) were positive for BTB by RT; acid-fast bacilli were cultured from 29 of 89 animals (32.5%). None of the positive cultures yielded mycobacteria from the Mycobacterium tuberculosis complex but many environmental mycobacteria were isolated. Among these, Mycobacterium terrae was the most common. We demonstrated a high prevalence of environmental mycobacteria in wildlife, the role of which is unknown. Flagship rare endemic species such as the mountain nyala (Tragelaphus buxtoni) and the Ethiopian wolf (Canis simensis) may be at risk for BTB. We also assessed the utility of RT for field purposes.

Leishmania donovani complex (Kinetoplastida, Trypanosomatidae): comparison of deoxyribonucleic acid based techniques for typing of isolates from Ethiopia.

In Ethiopia, visceral leishmaniasis (VL) is an increasing public health concern. Recently, a new outbreak of VL claimed the lives of hundreds of Ethiopians. Mapping its distribution and the identification of the causative Leishmania species is important for proper use of resources and for control planning. The choice of appropriate typing technique is the key for determining the infecting species. Here we compared three deoxyribonucleic acid (DNA) based markers. We used, for the first time, cpbE and cpbF (cpbE/F) PCR-RFLP and demonstrated that it clearly differentiates Leishmania donovani from Leishmania infantum. The cpbE/F PCR-RFLP gave identical banding pattern for all L. donovani strains irrespective of their geographic origin. With the K26 (primers) PCR-RFLP, the L. donovani strains gave a banding pattern different from L. infantum and showed variation with geographic origin. The Ethiopian isolates typed as L. donovani by the PCR-RFLP of the cpbE/F (gene) and K26 (primers) showed two types of patterns with the T2/B4 (primers) PCR-RFLP; one group with L. infantum-like and the other L. donovani-like pattern. Phylogenetic analysis using cpbE/F sequences showed variation with geographic origin of strains and the African strains of L. donovani are more distantly related to L. infantum. Moreover, the Ethiopian isolates were seen to be closely related to the Sudanese, Kenyan and Indian strains. Thus, we recommend the use of more than one marker to study the population genetics of L. donovani complex.

Leishmania (Kinetoplastida): species typing with isoenzyme and PCR-RFLP from cutaneous leishmaniasis patients in Ethiopia.

Cutaneous leishmaniasis (CL) is an increasing public health problem in Ethiopia. There is a concern that it is spreading with increased incidence. In this study, we used isoenzyme electrophoresis and internal transcribed spacer one (ITS1) PCR-RFLP techniques to identify Leishmania species from CL patients in Ethiopia. We obtained isolates from 55 localized cutaneous leishmaniasis (LCL), 3 diffused cutaneous leishmaniasis (DCL) and 36 biopsy samples from 34 LCL and 2 DCL cases from All Africa Leprosy and Tuberculosis Rehabilitation and Training Center (ALERT) and clinically diagnosed CL cases from Ochollo village. Both isoenzyme and ITS1 PCR-RFLP techniques showed that Leishmania aethiopica (L. aethiopica) was the aetiologic agent in all cases. Our study also showed that ITS1 PCR-RFLP could identify Leishmania species from biopsy samples and suggests the method could be used for epidemiological surveillance of leishmaniasis in Ethiopia and for species-specific diagnosis.