[An outbreak of human Streptococcus suis serotype 2 infections presenting with toxic shock syndrome in Sichuan, China].
OBJECTIVE
In mid-July 2005, five patients presented with septic shock to a hospital in Ziyang city in Sichuan, China, to identify the etiology of the unknown reason disease, an epidemiological, clinical, and laboratory study were conducted.


METHODS
An enhanced surveillance program were established in Sichuan, the following activities were introduced: active case finding in Sichuan of (a) laboratory diagnosed Streptococcus suis infection and (b) clinically diagnosed probable cases with exposure history; supplemented by (c) monitoring reports on meningococcal meningitis. Streptococcus suis serotype 2 infection was confirmed by culture and biochemical reactions, followed by sequencing for specific genes for serotype and virulence factors.


RESULTS
From June 10 to August 21, 2005, 68 laboratory confirmed cases of human Streptococcus suis infections were reported. All were villagers who gave a history of direct exposure to deceased or sick pigs in their backyards where slaughtering was performed. Twenty six (38%) presented with toxic shock syndrome of which 15 (58%) died. Other presentations were septicaemia or meningitis. All isolates were tested positive for genes for tuf, species-specific 16S rRNA, cps2J, mrp, ef and sly. There were 136 clinically diagnosed probable cases with similar exposure history but incomplete laboratory investigations.


CONCLUSIONS
An outbreak of human Streptococcus suis serotype 2 infections occurred in villagers after direct exposure to deceased or sick pigs in Sichuan. Prohibition of slaughtering in backyards brought the outbreak to a halt. A virulent strain of the bacteria is speculated to be in circulation, and is responsible for the unusual presentation of toxic shock syndrome with high case fatality.
Yang
Wei-zhong
WZ
Office for Disease Control and Emergency Response, Chinese Center for Disease Control and Prevention, Beijing 100050, China. ywz126@vip.sina.com
Yu
Hong-jie
HJ
Jing
Huai-qi
HQ
Xu
Jian-guo
JG
Chen
Zhi-hai
ZH
Zhu
Xiao-ping
XP
Wang
Hua
H
Liu
Xue-cCheng
XC
Wang
Shi-wen
SW
Liu
Lun-guang
LG
Zu
Rong-qiang
RQ
Luo
Long-ze
LZ
Xiang
Ni-juan
NJ
Liu
Hong-lu
HL
Zhong
Wen-jun
WJ
Liu
Li
L
Meng
Ling
L
Yuan
Heng
H
Gao
Yong-jun
YJ
DU
Hua-mao
HM
Ou
Yang-bin
YB
Ye
Chang-yun
CY
Jin
Dong
D
Lv
Qiang
Q
Cui
Zhi-gang
ZG
Huang
Yan
Y
Zhang
Shou-yin
SY
An
Xiang-dong
XD
Huang
Ting
T
Zhou
Xing-yu
XY
Feng
Liao
L
Pang
Qi-di
QD
Shu
Yue-long
YL
Wang
Yu
Y
D000818:Animals; D016470:Bacteremia / Q000453:epidemiology / Q000382:microbiology; D002681:China / Q000453:epidemiology; D004196:Disease Outbreaks; D006801:Humans; D016920:Meningitis, Bacterial / Q000453:epidemiology / Q000382:microbiology; D012772:Shock, Septic / Q000453:epidemiology* / Q000382:microbiology*; D013290:Streptococcal Infections / Q000453:epidemiology* / Q000382:microbiology* / Q000662:veterinary; D017011:Streptococcus suis / Q000302:isolation & purification*; D013552:Swine; D013553:Swine Diseases / Q000382:microbiology