无乳链球菌致病性研究进展

doi:10.16431/j.cnki.1671-7236.2024.03.040

摘要/Abstract

摘要： 无乳链球菌(Streptococcus agalactiae)是一种分布广泛的人兽共患性致病菌,通过形成生物膜可在奶牛乳腺中黏附、定植并长期存活,同时增强对宿主免疫防御的抵抗,引起奶牛乳腺感染而发生亚临床型乳腺炎,是全球范围内引起奶牛乳腺炎的最常见病原体之一,给奶牛养殖业和奶业造成巨大的经济损失。此外,其还可感染骆驼与罗非鱼等多种动物,造成严重的动物福利恶化,且存在人与动物间接传播的可能。无乳链球菌是一种革兰阳性机会致病菌,可在健康成年人的胃肠道及泌尿生殖道中无症状定植,感染新生儿可导致危及生命的败血症及脑膜炎的发生,并常伴有严重的神经系统后遗症。近年来,成人无乳链球菌感染的发病率呈上升趋势,尤其是对孕妇、老年人及免疫力低下的人群具有更高的易感率,可引起皮肤和软组织感染以及更为严重的败血症、脑膜炎和心内膜炎等疾病的发生。尽管使用抗生素治疗可部分缓解症状,但耐药菌株的出现和传播使得抗生素的治疗效果逐步下降,对无乳链球菌感染的控制愈发困难。笔者就无乳链球菌对多种动物及不同人群的致病性进行综述,以期为无乳链球菌的综合防控提供参考。

关键词: 无乳链球菌; 感染; 致病性

Abstract: Streptococcus agalactiae (S. agalactiae) is a widely distributed zoonotic pathogen.It can survive indefinitely in mammary glands of cows,by forming a biofilm that allows them to adhere and persist in the mammary gland,concomitantly enhancing resistance to host immune defense.S. agalactiae causes sub-clinical mastitis,which is one of the most common pathogens leading to mastitis in dairy herds worldwide,which causes huge economic losses to dairy industry.In addition,S. agalactiae can also infect various animals such as Camelus and Oreochromis niloticus,causing serious deterioration in animal welfare,and there is a possibility of indirect transmission between humans and animals. S. agalactiae is a Gram positive opportunistic pathogen that can asymptotically colonize the gastrointestinal and urogenital tracts of healthy adults.Infection of newborns can lead to life-threatening sepsis and meningitis,often accompanied by severe neurological sequelae.In recent years,the incidence rate of adult S. agalactiae infection is on the rise,especially for pregnant women,the elderly and people with low immunity.It can cause skin and soft tissue infections and more serious septicemia,meningitis,endocarditis and other diseases.Although the symptoms can be partially alleviated by treatment with antibiotics,the emergence and spread of drug-resistant strains have gradually reduced the effectiveness of treatment,and the control of S. agalactiae infection becomes more and more difficult.In this paper,the author summarized the pathogenicity of S. agalactiae to humans and different animals,in order to provide reference for the prevention and control of S. agalactiae.

Key words: Streptococcus agalactiae; infection; pathogenicity

中图分类号:

S852.61

陈晶, 马骏, 范钊玮, 刘慧婷, 崔玉东. 无乳链球菌致病性研究进展[J]. 中国畜牧兽医, 2024, 51(3): 1277-1285.

CHEN Jing, MA Jun, FAN Zhaowei, LIU Huiting, CUI Yudong. Research Progress on Pathogenicity of Streptococcus agalactiae[J]. China Animal Husbandry & Veterinary Medicine, 2024, 51(3): 1277-1285.

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