Isolation and molecular characterization of Mycobacterium bovis from Kafue lechwe (Kobus leche kafuensis) from Zambia

Abstract

Bovine tuberculosis (BTB) is a chronic bacterial disease caused by Mycobacterium bovis. Infections due to M. bovis, which serves as a stable reservoir, can pose serious challenge to control and eradicate in both wildlife and livestock at the interface. This study aimed at isolating and characterizing M. bovis from Kafue lechwe (Kobus leche kafuensis) and black lechwe (Kobus leche smithemani) at the animal/human interface in Zambia. The samples with lesions compatible with BTB collected during the hunting seasons of 2009 and 2010 were cultured for isolation of mycobacteria using Stonebrink with pyruvate (BD Diagnostics, MD, USA) and Middlebrook 7H10 (BD Diagnostics) slants. Isolated mycobacteria were identified using IS6110 polymerase chain reaction and deletion analysis. Molecular characterization of the isolates was performed using spoligotyping and mycobacteria interspersed repetitive unit-variable number tandem repeat (MIRU-VNTR) with nine loci. Data was analyzed using BioNumerics software 6.1. Out of the 39 samples, acid fast bacilli were detected in 27 (69.2 %) based on smear microscopy. Seven isolates were found to belong to Mycobacterium tuberculosis complex, and all were identified as M. bovis based on deletion analysis. All seven isolates were identical on spoligotyping as belonging to the SB0120 (SIT 482). MIRU-VNTR differentiated the isolates into five different patterns. This study has confirmed that M. bovis circulates in the Kafue lechwe, and non-tuberculous mycobacteria were detected in the black lechwe in Zambia which represents a wildlife reservoir, with a potential to spillover to cattle and humans. Isolates of M. bovis from lechwe antelopes are much conserved as only one spoligotype was detected. The study has shown that three loci differentiated fairly well. This option is cheap and less laborious, and hence a better option in resource-strained country like Zambia. The study further showed that some of the loci recommended by the European Reference Laboratory are not suitable for typing M. bovis in Zambia.

Molecular characterization of bovine tuberculosis strains in two slaughterhouses in Morocco

“…The second most frequent spoligotype was SB0265 which was reported as the second most frequent in the United States from a set of strains collected between 1989 and 2013 [ 44 ], in addition, this spoligotype was isolated in Tunisia from a strain coming from Morocco [ 33 ], and was also reported in many European countries [ 45 , 46 ], as well as in Taiwan [ 47 ]. The spoligopattern SB0120 had the frequency of 11.7% in our sample size and was reported previously in France from a sample originating from Morocco (SITVIT database), it was also reported in many African countries like Algeria [ 41 ], Tunisia [ 42 ] and Zambia [ 48 ] as well as in Argentina and Spain [ 43 , 49 ]. Our study shows no similar spoligotype pattern with Mali, indicating that the Sahara desert and the long distance between cattle rearing areas (cattle are only kept until a Latitude of 12 degrees in Mali) seem to be an effective barrier for the transmission of M. bovis and/or that there is probably little trade of cattle between Morocco and Mali [ 36 ].…”

Characterization ofMycobacterium bovisfrom Humans and Cattle in Namwala District, Zambia

“…These tools can help to determine the origin of outbreaks, show the relationships of TB in domestic and wild animals, and identify the sources of human infection [13]. Bovine TB has been reported to be endemic in traditional livestock and in wildlife in Namwala district [14–16]. It has, however, been speculated that zoonotic TB could occur in humans based on the cultural activities of the people in this area such as consumption of raw milk [17, 18].…”

Isolation and characterization of non tuberculous mycobacteria from humans and animals in Namwala District of Zambia

“…In this paper we only report the NTMs isolated from humans, cattle and Kafue lechwe. The Mycobacterium tuberculosis complex has been reported elsewhere [ 20 – 22 ].…”