Nelson Mandela African Institution of Science and Technology, Arusha, Tanzania.
Kilimanjaro Clinical Research Institute, Moshi, Tanzania.
Front Public Health. 2024 Nov 1;12:1478494. doi: 10.3389/fpubh.2024.1478494. eCollection 2024.
Brucellosis remains a significant health and economic challenge for livestock and humans globally. Despite its public health implications, the factors driving the endemic persistence of at the human-livestock interface in Tanzania remain poorly elucidated. This study aimed to identify the seroprevalence of infection in livestock and humans within a ranching system and determine associated risk factors for disease endemicity.
A cross-sectional sero-epidemiological study was conducted in 2023 in Tanzania's Karagwe District, involving 725 livestock (cattle, goats, sheep) from 10 herds and 112 humans from associated camps. Seroprevalence was assessed using competitive ELISA while epidemiological data were collected via questionnaires. Generalized Linear Models and Contrast Analysis were used to identify risk factors for infection.
Overall seroprevalence was 34% in livestock and 41% in humans. Goats exhibited the highest prevalence (69.2%), while cattle had the lowest (22.6%). Mixed-species herds (Odds Ratio, OR = 2.96, CI [1.90-4.60]) and small ruminants-only herds (OR = 6.54, CI [3.65-11.72]) showed a significantly higher risk of seropositivity compared to cattle-only herds. Older cattle (OR = 5.23, CI [2.70-10.10]) and lactating females (OR = 2.87, CI [1.78-4.63]) represented significant risks for brucellosis in livestock. In humans, close contact with animals (OR = 7.20, CI [1.97-36.31]) and handling animals during parturition or aborted fetuses (OR = 2.37, CI [1.01-5.58]) were significant risk factors. Notably, no spatial association was found in seroprevalence between herds and nearby human communities.
The lack of spatial correlation between livestock and human seroprevalence suggests complex transmission dynamics, potentially involving endemic circulation in livestock and human infections from multiple sources of exposure to livestock. This study highlights the need for comprehensive zoonotic risk education and targeted intervention strategies. Further research is crucial to elucidate transmission pathways and improve infection control. This includes developing robust methods for identifying infective species and implementing effective strategies to mitigate infection in endemic regions.
布鲁氏菌病仍然是一个重大的全球公共卫生和经济挑战，无论是对牲畜还是人类而言。尽管它具有公共卫生意义，但在坦桑尼亚，导致人畜接触界面上地方性持续存在的因素仍未得到充分阐明。本研究旨在确定牧场系统中牲畜和人类感染的血清流行率，并确定疾病地方性的相关危险因素。
2023 年在坦桑尼亚的卡盖拉区进行了一项横断面血清流行病学研究，涉及来自 10 个畜群的 725 头牲畜（牛、山羊、绵羊）和来自相关营地的 112 名人类。使用竞争性 ELISA 评估血清流行率，同时通过问卷调查收集流行病学数据。使用广义线性模型和对比分析来确定感染的危险因素。
总体而言，牲畜的血清流行率为 34%，人类为 41%。山羊的流行率最高（69.2%），而牛的流行率最低（22.6%）。混合物种畜群（比值比，OR=2.96，CI [1.90-4.60]）和仅小反刍动物畜群（OR=6.54，CI [3.65-11.72]）与仅牛畜群相比，血清阳性的风险显著更高。年龄较大的牛（OR=5.23，CI [2.70-10.10]）和哺乳期雌性（OR=2.87，CI [1.78-4.63]）是牛群中布鲁氏菌病的显著风险因素。在人类中，与动物密切接触（OR=7.20，CI [1.97-36.31]）和在分娩或流产胎儿期间处理动物（OR=2.37，CI [1.01-5.58]）是显著的危险因素。值得注意的是，畜群和附近人类社区之间的血清流行率没有发现空间相关性。
牲畜和人类血清流行率之间缺乏空间相关性表明存在复杂的传播动态，可能涉及牲畜中的地方性循环和人类感染的多种暴露源。本研究强调了需要进行全面的人畜共患病风险教育和针对性的干预策略。进一步的研究对于阐明传播途径和改善感染控制至关重要。这包括开发识别感染物种的可靠方法，并实施有效的策略来减轻地方性地区的感染。
