Abstract：
BACKGROUND: Brucella suis is a zoonotic pathogen with a serious impact on public health and the pig industry worldwide. Information regarding B. suis in pigs in Egypt is scarce. This study aimed to investigate the prevalence of B. suis in slaughtered domestic pigs at El-Basatin abattoir in Cairo, Egypt. A total of 1,116 domestic pigs slaughtered in 2020 were sampled for Brucella isolation and identification. Identified Brucella isolates were molecularly confirmed at species, and biovar levels using Bruce ladder PCR and Suis ladder multiplex PCR. Additionally, high-risk practices of 16 abattoir workers (4 veterinarians, 10 butchering and evisceration workers, and 2 scalding workers) were investigated using a pre-piloted structured questionnaire.
RESULTS: Brucella isolates were recovered from 1.3% of examined pigs (n = 14) at consistently low rates (1.1-2.9%) across the year of sampling from February to December 2020. All isolates were confirmed as B. suis biovar (bv) 2. Remarkably, 92.9% (13/14) of isolates showed atypical ability to produce H2S and hence were considered as B. suis bv2 atypical phenotype. The prevalence was higher in males (1.8%) than in females (0.9). However, this difference was not significant (Odds ratio = 1.9; CI 95% 0.7 - 5.7; P = 0.2). No detectable pathological lesions were associated with B. suis bv2 infection in examined pigs. All strains were isolated from cervical lymph nodes, highlighting a potential oral transmission. High-risk practices were recorded among swine abattoir workers in this study: 75% do not wear gloves or disinfect their knives daily, and 18.8% were willing to work with open wound injuries.
CONCLUSIONS: To the best of our knowledge, this is the first isolation of B. suis bv2 in Egypt. Detection of H2S producing B. suis bv2 atypical phenotype is alarming as it may result in misinterpretation of these isolates as highly human pathogenic B. suis bv1 in Egypt and possibly elsewhere. Further epidemiological tracing studies are crucial for the detection of the origin of this biovar. Including pigs in the national surveillance program of brucellosis, and an education program for swine abattoir workers about occupational risk of B. suis is a need in Egypt.
RESULTS: Brucella isolates were recovered from 1.3% of examined pigs (n = 14) at consistently low rates (1.1-2.9%) across the year of sampling from February to December 2020. All isolates were confirmed as B. suis biovar (bv) 2. Remarkably, 92.9% (13/14) of isolates showed atypical ability to produce H2S and hence were considered as B. suis bv2 atypical phenotype. The prevalence was higher in males (1.8%) than in females (0.9). However, this difference was not significant (Odds ratio = 1.9; CI 95% 0.7 - 5.7; P = 0.2). No detectable pathological lesions were associated with B. suis bv2 infection in examined pigs. All strains were isolated from cervical lymph nodes, highlighting a potential oral transmission. High-risk practices were recorded among swine abattoir workers in this study: 75% do not wear gloves or disinfect their knives daily, and 18.8% were willing to work with open wound injuries.
CONCLUSIONS: To the best of our knowledge, this is the first isolation of B. suis bv2 in Egypt. Detection of H2S producing B. suis bv2 atypical phenotype is alarming as it may result in misinterpretation of these isolates as highly human pathogenic B. suis bv1 in Egypt and possibly elsewhere. Further epidemiological tracing studies are crucial for the detection of the origin of this biovar. Including pigs in the national surveillance program of brucellosis, and an education program for swine abattoir workers about occupational risk of B. suis is a need in Egypt.
摘要：
背景：猪布鲁氏菌是一种人畜共患病原体，对全球公共卫生和养猪业产生严重影响。有关埃及猪猪链球菌的信息很少。这项研究旨在调查在开罗的El-Basatin屠宰场屠宰的家猪中猪双歧杆菌的患病率，埃及。对2020年屠宰的1,116头猪进行了布鲁氏菌分离鉴定。鉴定的布鲁氏菌分离株在物种上进行了分子确认，使用Bruce梯形PCR和Suis梯形多重PCR和biovar水平。此外,16名屠宰场工人的高风险做法(4名兽医，10名屠宰和内脏工人，和2名烫伤工人）使用预先试点的结构化问卷进行调查。
结果：在2020年2月至12月的采样年中，从1.3％的受检猪（n=14）中以一贯较低的比率（1.1-2.9％）回收了布鲁氏菌分离株。所有分离物均被证实为猪双歧杆菌(bv)2。值得注意的是,92.9%(13/14)的分离物表现出产生H2S的非典型能力,因此被认为是猪芽孢杆菌bv2非典型表型。男性的患病率（1.8％）高于女性（0.9）。然而,差异不显著(赔率=1.9;CI95%0.7-5.7;P=0.2).在检查的猪中，没有可检测到的病理性病变与猪链球菌bv2感染有关。所有菌株均从颈部淋巴结中分离，突出潜在的口头传播。在这项研究中记录了猪屠宰场工人的高风险做法：75％的人每天不戴手套或消毒刀，18.8%的人愿意在开放性伤口受伤的情况下工作。
结论：据我们所知，这是B.suisbv2在埃及的第一次隔离。检测到产生H2S的B.suisbv2非典型表型令人震惊，因为它可能导致将这些分离株误解为埃及和其他地方的高度人类致病性B.suisbv1。进一步的流行病学追踪研究对于检测这种生物变量的起源至关重要。包括布鲁氏菌病国家监测计划中的猪，埃及需要针对猪屠宰场工人的职业风险教育计划。
结果：在2020年2月至12月的采样年中，从1.3％的受检猪（n=14）中以一贯较低的比率（1.1-2.9％）回收了布鲁氏菌分离株。所有分离物均被证实为猪双歧杆菌(bv)2。值得注意的是,92.9%(13/14)的分离物表现出产生H2S的非典型能力,因此被认为是猪芽孢杆菌bv2非典型表型。男性的患病率（1.8％）高于女性（0.9）。然而,差异不显著(赔率=1.9;CI95%0.7-5.7;P=0.2).在检查的猪中，没有可检测到的病理性病变与猪链球菌bv2感染有关。所有菌株均从颈部淋巴结中分离，突出潜在的口头传播。在这项研究中记录了猪屠宰场工人的高风险做法：75％的人每天不戴手套或消毒刀，18.8%的人愿意在开放性伤口受伤的情况下工作。
结论：据我们所知，这是B.suisbv2在埃及的第一次隔离。检测到产生H2S的B.suisbv2非典型表型令人震惊，因为它可能导致将这些分离株误解为埃及和其他地方的高度人类致病性B.suisbv1。进一步的流行病学追踪研究对于检测这种生物变量的起源至关重要。包括布鲁氏菌病国家监测计划中的猪，埃及需要针对猪屠宰场工人的职业风险教育计划。
