National Institute of Cholera and Enteric Diseases, Kolkata, India,
Curr Top Microbiol Immunol. 2014;379:49-85. doi: 10.1007/82_2014_368.
Cholera is a global health problem as several thousands of cases and deaths occur each year. The unique epidemiologic attribute of the disease is its propensity to occur as outbreaks that may flare-up into epidemics, if not controlled. The causative bacterial pathogen Vibrio cholerae prevails in the environment and infects humans whenever there is a breakdown in the public health component. The Indian subcontinent is vulnerable to this disease due its vast coastlines with areas of poor sanitation, unsafe drinking water, and overcrowding. Recently, it was shown that climatic conditions also play a major role in the persistence and spread of cholera. Constant change in the biotypes and serotypes of V. cholerae are also important aspects that changes virulence and survival of the pathogen. Such continuous changes increase the infection ability of the pathogen affecting the susceptible population including the children. The short-term carrier status of V. cholerae has been studied well at community level and this facet significantly contributes to the recurrence of cholera. Several molecular tools recognized altering clonality of V. cholerae in relation with the advent of a serogroup or serotype. Rapid identification systems were formulated for the timely detection of the pathogen so as to identify and control the outbreak and institute proper treatment of the patients. The antimicrobials used in the past are no longer useful in the treatment of cholera as V. cholerae has acquired several mechanisms for multiple antimicrobial resistance. This upsurge in antimicrobial resistance directly influences the management of the disease. This chapter provides an overview of cholera prevalence in India, possible sources of infection, and molecular epidemiology along with antimicrobial resistance of V. cholerae.
霍乱是一个全球性的健康问题,每年都有数千例病例和死亡。该疾病的独特流行病学特征是其倾向于爆发,如不加以控制,可能会爆发为流行。致病细菌病原体霍乱弧菌在环境中普遍存在,只要公共卫生环节出现故障,就会感染人类。由于印度次大陆拥有广阔的海岸线,卫生条件差、饮用水不安全和人口拥挤,因此容易受到这种疾病的影响。最近,研究表明气候条件也在霍乱的持续和传播中起着重要作用。霍乱弧菌的生物型和血清型的不断变化也是影响病原体毒力和存活的重要方面。这种持续的变化增加了病原体的感染能力,影响到包括儿童在内的易感人群。霍乱弧菌的短期携带者状态在社区层面上已经得到了很好的研究,这一特征对霍乱的复发有重要贡献。几种分子工具被用来识别与血清群或血清型出现相关的霍乱弧菌的克隆性变化。已经制定了快速识别系统,以便及时检测病原体,从而识别和控制疫情,并对患者进行适当的治疗。过去使用的抗生素在治疗霍乱方面已经不再有效,因为霍乱弧菌已经获得了多种对抗生素的多重耐药机制。这种对抗生素的耐药性的上升直接影响到疾病的管理。本章概述了印度的霍乱流行情况、可能的感染源以及霍乱弧菌的分子流行病学和抗生素耐药性。