A Review of Bovine Tuberculosis in the Kafue Basin Ecosystem

The Kafue basin ecosystem is the only remaining natural habitat for the endangered Kafue lechwe antelope (Kobus leche Kafuensis). However, hydroelectricity power production, large-scale sugar plantations, commercial fishing and increasing livestock production are threatening its natural existence and sustainability. Further, increasing human settlements within and around the Kafue basin have resulted in decreased grazing grounds for the Kafue lechwe antelopes despite a corresponding increase in cattle population sharing the same pasture. Baseline epidemiological data have persistently reported findings of bovine tuberculosis (BTB) in both wild and domestic animals, although these have been deficient in terms of describing direct evidence in the role of either lechwe antelopes or cattle in the reported observations. Despite the current literature being deficient in establishing the casual role and transmission patterns of BTB, a bimodal route of infection at the livestock/wildlife interface has been postulated. Likewise, it is not known how much of (BTB) has the potential of causing disease in humans. This paper, seeks to underline those aspects that need further research and update available data on BTB in the Kafue basin with regards to the prevalence, distribution, risk factors, threats on wildlife conservation, livestock production, public health implications, and possible mitigatory measures

A Review of Ecological Factors Associated with the Epidemiology of Wildlife Trypanosomiasis in the Luangwa and Zambezi Valley Ecosystems of Zambia

Trypanosomiasis has been endemic in wildlife in Zambia for more than a century. The disease has been associated with neurological disorders in humans. Current conservation strategies by the Zambian government of turning all game reserves into state-protected National Parks (NPs) and game management areas (GMAs) have led to the expansion of the wildlife and tsetse population in the Luangwa and Zambezi valley ecosystem. This ecological niche lies in the common tsetse fly belt that harbors the highest tsetse population density in Southern Africa. Ecological factors such as climate, vegetation and rainfall found in this niche allow for a favorable interplay between wild reservoir hosts and vector tsetse flies. These ecological factors that influence the survival of a wide range of wildlife species provide adequate habitat for tsetse flies thereby supporting the coexistence of disease reservoir hosts and vector tsetse flies leading to prolonged persistence of trypanosomiasis in the area. On the other hand, increase in anthropogenic activities poses a significant threat of reducing the tsetse and wildlife habitat in the area. Herein, we demonstrate that while conservation of wildlife and biodiversity is an important preservation strategy of natural resources, it could serve as a long-term reservoir of wildlife trypanosomiasis

Detection of Parasites and Parasitic Infections of Free-Ranging Wildlife on a Game Ranch in Zambia: A Challenge for Disease Control

Ex-situ conservancies are expanding alternatives to livestock production in Zambia albeit the lack of information on circulating infectious parasites from wildlife. Therefore, 12 wildlife species were examined on a game ranch were all species were found to be infected by Rhipecephalus spp. Haemoparasite infections were estimated at 7.37% (n = 95) with Babesia spp. detected in bushbuck (Tragelaphus scriptus); Anaplasma marginale in impala (Aepyceros melampus) and puku (Kobus vardonii) for the first time in Zambia. The majority of worm species isolated from bovids were not detected in equids and, vice versa. Our findings intimate ecological and behavioural patterns of some animals as deterministic to exposure. Kafue lechwe (Kobus leche kafuensis) had the widest range of worm species with more infected organs than other animals suggesting their semi aquatic nature contributory to prolonged worm exposure compared to other animals. On the other hand, Kafue lechwe had the least tick infections attributable more to shorter attachment periods as they spend prolonged periods submerged in water. Our findings indicate the vital role that wildlife plays in the epidemiology of parasitic diseases. To reduce the infection burden, control measures should be focused on reducing transmission to highly susceptible animal species as described herein

Sarcoptes mite epidemiology and treatment in African buffalo (Syncerus caffer) calves captured for translocation from the Kafue game management area to game ranches

<p>Abstract</p> <p>Background</p> <p>In Zambia, translocation of wildlife from National Parks to private owned game ranches demands that only animals free of infectious diseases that could adversely affect the expansion of the wildlife industry should be translocated to game ranches. <it>Sarcoptes </it>mange (<it>Sarcoptes scarbiei</it>) has been involved in the reduction of wildlife populations in some species.</p> <p>Results</p> <p><it>Sarcoptes </it>mange (<it>Sarcoptes scarbiei</it>) was detected and eradicated from two herds of African buffalo (<it>Syncerus caffer</it>) calves captured in the Kafue GMA in July 2004 and August 2005. The overall prevalence was estimated at 89.5% (77/86). Sex had no influence on the occurrence and severity of the disease. Of the 86 calves used in the study, 72.1% had good body condition scores, 20.9% were fair and 7.0% were poor. Of the 77 infected calves, 53.2% were mildly infected, 28.6% were moderately and 18.2% were severely infected. Body condition score was correlated to the severity of the infection (r = 0.72, p < 0.000, <it>n </it>= 86) at capture. Eradication of <it>Sarcoptes </it>mites from the entire herd using ivermetcin was dependant on the severity of the infection. The overall ability of ivermectin to clear the infection after the first treatment was estimated at 81.8% (<it>n </it>= 77). It increased to 94.8% and 100% after the second and third treatments respectively.</p> <p>Conclusion</p> <p>This is the first report on the epidemiology and treatment of <it>Sarcoptes </it>mange in African buffaloes in Zambia. This study improves our understanding about <it>Sarcoptes scabiei </it>epidemiology and treatment which will have further applications for the safe animal translocation.</p

Isolation and characterization of Mycobacterium bovis strains from indigenous Zambian cattle using Spacer oligonucleotide typing technique

<p>Abstract</p> <p>Background</p> <p>Bovine tuberculosis (BTB), caused by <it>Mycobacterium bovis</it>, has remained a major source of concern to public health officials in Zambia. Previous investigations have used traditional epidemiological methods that are unable to identify the causative agent and from which dynamics of disease dispersion is difficult to discern. The objective of this study was to isolate, characterize and determine the genetic diversity and relatedness of <it>M. bovis </it>from major cattle rearing districts in Zambia by spoligotyping. A total of 695 carcasses were examined and 98 tissues had gross post-mortem lesions compatible with BTB.</p> <p>Results</p> <p>Forty-two out of the ninety-eight suspected tissues examined had culture properties characteristic of mycobacteria from which 31 isolates yielded interpretable spoligotypes. This technique showed good discriminatory power (HGDI = 0.98), revealing 10 different spoligotype patterns. Twenty-seven isolates belonged to one cluster with more than 95% similarity and inside the cluster, one predominant spoligotype was found in 20 (64.5%) of the isolates tested. The highest number of spoligotypes was observed among samples from Namwala district. Spoligotypes from 26 (83.9%) of the isolates belonged to five spoligotypes that have been reported before while the remaining 5 (16.1%) isolates had unique spoligotypes that are being reported for the first time; these have been assigned numbers SB1763 to SB1767. Five of the 6 districts had the predominant spoligotype (SB0120).</p> <p>Conclusion</p> <p>The study has described the dispersion patterns of <it>M. bovis </it>in Zambian cattle for the first time and has identified 5 spoligotype patterns specific to Zambia. The observation of an overlap in the spoligotype pattern SB0120 in 5 of the 6 districts suggests the probability of sharing a common source of infection.</p

Evaluation of the level of awareness of congenital toxoplasmosis and associated practices among pregnant women and health workers in Tanzania\u2019s Temeke district in Dar es Salaam

Background: Toxoplasmosis caused by the obligate intracellular coccidian protozoan Toxoplasma gondii (T. gondii) infects all warm-blooded animals including humans. This parasite may develop in both immune-compromised and immunocompetent hosts but usually the disease manifestations strongly differ according to immune status. Immunocompromised hosts develop more severe disease than immunocompetent hosts. Infections in pregnancy carry the risk of foetal involvement and can lead to serious clinical outcomes including psychomotor and ocular disorders in congenitally infected foetuses and children. Objective: To assess the level of awareness and practices towards congenital toxoplasmosis among health workers and pregnant women in Tanzania\u2019s Temeke municipality. Methods: This was a cross-sectional study involving 371 pregnant women and 22 health workers from six healthcare facilities in Temeke municipality of Dar es Salaam, Tanzania. A structured questionnaire and review of prenatal screening forms were used to collect information. The questionnaire focused on knowledge of disease aetiology, signs and symptoms, modes of transmission, treatment and management. Results: Of the pregnant women, 96% (95% CI: 0. 94-0.98) were unaware of the disease, had never heard, read or seen any information regarding toxoplasmosis. The majority of respondents including those who had heard, read or seen information concerning toxoplasmosis were unaware of the disease aetiology, signs and symptoms. However, 90% (95% CI: 0.86\u20130.93) of respondents unknowingly observed preventive practices towards the disease including avoiding eating raw, cured or rare meat. There was a significant statistical relationship between practices towards toxoplasmosis and age of pregnant women, such that for every increase in age by ten years the risk practices towards toxoplasmosis increased by 41% (OR=1.41, 95%, C.I. 1.05-1.90). Preventive practices towards toxoplasmosis decreased significantly by 74% and 78% for the age of 19-25 and 26-35 years old pregnant women respectively, as compared to those &lt; 19 years. No significant difference was observed for those aged &gt; 35 years. Multigravidae was associated with at-risk practices towards toxoplasmosis (OR=2.65, CI: 1.38-5.08). Of the 22 health workers who participated in the study, 36% (95% CI: 0.15\u20130.58) were aware of the congenital toxoplasmosis and its clinical outcomes. None of them had diagnosed the disease before. Conclusion: Due to general lack of awareness towards toxoplasmosis observed among both health workers and pregnant women in Temeke Municipality, we recommend health policy on maternal and child healthcare to address prenatal screening that is aimed at providing early diagnosis for any possible congenital toxoplasmosis as well as diseases that are currently screened in Tanzania such as HIV, syphilis and malaria. Integrating a One Health approach in educating medical professionals and the vulnerable population of pregnant women on the importance of congenital zoonoses will promote awareness and preventive practices towards the disease

Comparative Intradermal Tuberculin Testing of Free-Ranging African Buffaloes (Syncerus caffer) Captured for Ex Situ Conservation in the Kafue Basin Ecosystem in Zambia

Bovine tuberculosis (BTB) is endemic in African buffaloes (Syncerus caffer) in some National Parks in Southern Africa, whilst no studies have been conducted on BTB on buffalo populations in Zambia. The increased demand for ecotourism and conservation of the African buffalo on private owned game ranches has prompted the Zambian Wildlife Authority (ZAWA) and private sector in Zambia to generate a herd of “BTB-free buffaloes” for ex situ conservation. In the present study, 86 African buffaloes from four different herds comprising a total of 530 animals were investigated for the presence of BTB for the purpose of generating “BTB free” buffalo for ex-situ conservation. Using the comparative intradermal tuberculin test (CIDT) the BTB status at both individual animal and herd level was estimated to be 0.0% by the CIDT technique. Compared to Avian reactors only, a prevalence of 5.8% was determined whilst for Bovine-only reactors a prevalence of 0.0% was determined. These results suggest the likelihood of buffalo herds in the Kafue National Park being free of BTB