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Bovine tuberculosis (TB) caused by Mycobacterium bovis is a significant health threat to cattle and a zoonotic threat for humans in many developing countries. Rapid and accurate detection of M. bovis is fundamental for controlling the disease in animals and humans, and for the proper treatment of patients as one of the first-line anti-TB drug, pyrazinamide, is ineffective against M. bovis. Currently, there are no rapid, simplified and low-cost diagnostic methods that can be easily integrated for use in many developing countries. Here, we report the development of a loop-mediated isothermal amplification (LAMP) assay for specific identification of M. bovis by targeting the region of difference 4 (RD4), a 12.7 kb genomic region that is deleted solely in M. bovis. The assay's specificity was evaluated using 139 isolates comprising 65 M. bovis isolates, 40 M. tuberculosis isolates, seven M. tuberculosis complex reference strains, 22 non-tuberculous mycobacteria and five other bacteria. The established LAMP detected only M. bovis isolates as positive and no false positives were observed using the other mycobacteria and non-mycobacteria tested. Our LAMP assay detected as low as 10 copies of M. bovis genomic DNA within 40 minutes. The procedure of LAMP is simple with an incubation at a constant temperature. Results are observed with the naked eye by a color change, and there is no need for expensive equipment. The established LAMP can be used for the detection of M. bovis infections in cattle and humans in resource-limited areas. Author summary: Although bovine tuberculosis in humans has been eliminated in developed countries, the disease remains a challenge in many developing countries. Routine laboratory methods used to identify tuberculosis (TB) in high-burden countries do not distinguish between the two main causes of TB in humans, namely Mycobacterium tuberculosis and M. bovis. In addition, M. bovis is naturally resistant to one of the first-line drugs used to treat TB called pyrazinamide; therefore, accurate diagnosis of M. bovis is important for proper selection of anti TB drugs. In cattle, surveillance for M. bovis infection is important to obtain data on bovine TB burden and hence provide a basis for the establishment and/or improvement of control programs. In this study, a loop-mediated isothermal amplification (LAMP) based method was developed to identify M. bovis. This LAMP method detected M. bovis within 40 minutes following incubation at constant temperature (66°C) in a battery-powered incubator and results could be read with the naked eye following development of a color change. Our results elaborate a rapid and low-cost LAMP based method for detection and surveillance of M. bovis infection in cattle and humans in resource-limited, endemic areas. [ABSTRACT FROM AUTHOR]

Trade in animals and animal products is a key factor in the transmission of infectious diseases. Livestock traders play an important role in this process, yet there is little knowledge of traders' perceptions of animal disease or their associated actions. The aim of this study was to investigate perceptions and practices of Zambian small ruminant traders with regard to sheep and goat health and disease. It also analysed how existing perceptions and practices might affect risks of disease transmission through trade. A case study was performed at the two largest small livestock markets in Zambia: the Lusaka market in the capital and the Kasumbalesa market near the border with the Democratic Republic of Congo. Semi-structured interviews with 47 traders performed in April-May and September 2018 represent the core material. Zambian small ruminant traders frequently trade animals that have clinical signs of disease, either because they appear unaware or indifferent to the associated risks, experience financial constraints or assign responsibility for disease prevention to other value chain actors. In their decision about whether or not to sell a visibly sick small ruminant, traders appear to consider whether the clinical sign is perceived as 'natural' or the result of an illness, whether the buyer is aware of the animal's health condition, and whether the animal is sold for consumption or breeding purposes. Traders appear to regard the veterinary certificate required to transport small ruminants in Zambia as proof of health, placing the responsibility for potential disease in traded animals on the veterinary authorities. In their description of a model trader, taking good care of and being sensitive to customer needs was emphasized, indicating that an efficient way to encourage traders to change their behaviour is to influence customer demands. In contrast to the focus in previous studies on identifying and filling knowledge gaps, the present study show that lack of knowledge is not central to why traders engage in disease-transmitting behaviour. Greater awareness of other reasons for certain perceptions and practices could lead to the formulation of risk communication strategies and mitigation measures that are relevant for the local context, as well as alternative strategies for changing trader behaviour. [ABSTRACT FROM AUTHOR]

The article reports on a symposium in which Human African Trypanosomiasis (HAT) was discussed. It states that this neglected tropical disease is caused by Trypanosoma brucei rhodesiense or Trypanosoma brucei gambiense. It also states that the bite of an infected tsetse fly called Glossina species causes its transmission.

Background: Extended-spectrum beta-lactamase-producing Escherichia coli (ESBL-Ec) represents a significant global public health concern. The epidemiology of ESBL-Ec in Uganda is not well understood although it is harbored by humans, animals, and the environment. This study explains the epidemiology of ESBL-Ec using a one health approach in selected farming households in Wakiso district, Uganda., Methodology: Environmental, human, and animal samples were collected from 104 households. Additional data were obtained using observation checklists and through interviews with household members using a semi-structured questionnaire. Surface swabs, soil, water, human and animal fecal samples were introduced onto ESBL chromogenic agar. The isolates were identified using biochemical tests and double-disk synergy tests. To assess associations, prevalence ratios (PRs) were computed using a generalized linear model (GLM) analysis with modified Poisson and a log link with robust standard errors in R software., Results: Approximately 83% (86/104) households had at least one positive ESBL-Ec isolate. The overall prevalence of ESBL-Ec at the human-animal-environment interface was approximately 25.0% (95% CI: 22.7-28.3). Specifically, humans, animals and the environment had an ESBL-Ec prevalence of 35.4%, 55.4%, and 9.2% respectively. Having visitors (adj PR = 1.19, 95% CI: 1.04-1.36), utilizing veterinary services (adj PR = 1.39, 95% CI: 1.20-1.61) and using animal waste for gardening (adj PR = 1.29, 95% CI: 1.05-1.60) were positively associated with household ESBL-Ec contamination. Covering the drinking water container with a lid (adj PR = 0.84 95% CI: 0.73-0.96) was associated with absence of ESBL-Ec in a household., Conclusion: There is wider dissemination of ESBL-Ec in the environment, humans, and animals, indicating poor infection prevention and control (IPC) measures in the area. Improved collaborative one health mitigation strategies such as safe water chain, farm biosecurity, household and facility-based IPC measures are recommended to reduce the burden of antimicrobial resistance at community level., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Muleme et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)