Distribution and molecular characteristics of Vibrio cholerae O1 El Tor isolates recovered in Guangdong Province,China,1961-2013
作者单位：Department of Nutrition and Food HygieneSchool of Public Health and Tropical MedicineSouthern Medical University
会议名称：《2016新发传染病研究热点研讨会》
会议日期：2016年
学科分类：1004[医学-公共卫生与预防医学(可授医学、理学学位)] 100401[医学-流行病与卫生统计学] 10[医学]
关 键 词：Molecular characteristics Vibrio cholerae O1 El Tor Guangdong Province China
摘 要：China’s Guangdong Province is located along the same latitude as Kolkata,India and Dhaka,Bangladesh,and is also considered a source of epidemic cholera. However,molecular description and the genetic relationships between Vibrio cholerae O1 El Tor isolates in Guangdong remain unclear. In this study,381 clinical V. cholerae O1 isolates recovered from cholera cases presenting in Guangdong between 1961 and 2013 were investigated by PCR,amplicon sequencing and pulsed-field gel electrophoresis(PFGE). During this time frame,four distinct epidemic periods(1-4) were observed based on the different dominant serotype leading its epidemic,correspond to years;or time periods from/to 1961-1969,1978-1989, 1990-2000, 2001-2013, respectively. Molecular analysis of representative isolates indicated that a single dominating clone was associated with each epidemic stage. All isolates from period 1 and 2 carried the typical El Tor ctx B;this allele was displaced by classical ctx B beginning in 1993. However all isolated carried the El Tor-specific toxin-coregulated pili subunit A(tcp A). Isolates were grouped into five clusters on the basis of Not I enzyme digested PFGE,and the first four clusters were associated with specific periods,cluster Ⅰ(period 1),Ⅱ(period 3),Ⅲ(period 2) and Ⅳ(period 4),respectively. While cluster V consisted of isolates from all four epidemic periods, but was most heterogeneous in appearance. Our data indicate genetic variations that shape the relationship among emerging isolates of V. cholerae O1 in Guangdong Province contribute to the 7 global pandemic.