Analysis of Bacterial Pathogens Causing Acute Diarrhea on the Basis of Sentinel Surveillance in Shanghai, China, 2006–2011

Abstract

SUMMARY: Acute diarrhea is the most common infectious disease worldwide and its causes vary from one region to another. We aimed to analyze the spectrum and epidemiological characteristics of pathogens from 22,386 outpatients with acute diarrhea on the basis of surveillance data from Shanghai, China, during 2006-2011. The following 8 pathogens were isolated and identified using standard methods: Salmonella, Shigella, Vibrio cholerae, V. parahaemolyticus, enteropathogenic Escherichia coli, enterotoxigenic E. coli, enteroinvasive E. coli, and enterohemorrhagic E. coli. In total, 2,234 strains of pathogens were obtained and the overall isolation rate of these 8 pathogens gradually decreased from 17.1z in 2006 to 7.4z in 2011. V. parahaemolyticus was the most frequently identified pathogen, followed by Shigella and Salmonella. The isolation rate of V. parahaemolyticus notably varied by season, whereas Salmonella and Shigella infections showed little seasonal variation. Age-related variation was also observed. V. parahaemolyticus infection occurred more often in patients aged 20-40 years. S. enterica serovar Enteritidis and S. flexneri were the most common serotypes of Salmonella and Shigella, respectively. The descending trend observed in the isolation rate of pathogens from the current surveillance suggests an urgent requirement or improvement.

Incidence rates and clinical Symptoms of Salmonella, Vibrio parahaemolyticus, and Shigella infections in China, 1998–2013

“…Salmonella infections occurred all year round, were easy to contract from April to November, and occurred with a high incidence from May to October, consistent with previous reports of Salmonella infections in this region [3,13,18]. [25], which is in line with our data until 2010, but contrary to our findings of 2011 because Salmonella was the major cause of acute diarrhea during this period in our study until 2013, which might be due to the fact that in our study, small, region-limited Salmonella outbreaks have been detected. However, the percentage of V. parahaemolyticus cases in acute diarrhea patients gradually decreased from 2006-2011.…”

Case–control study of diarrheal disease etiology in individuals over 5 years in southwest China

“…Although the molecular biology techniques (e.g. PCR and Real-time PCR) are useful for detecting DEC, PCR was not used widely in medical facilities because of constraints in many developing countries, including the poor laboratory conditions, limited funds and low detection capacities of staff [16]. Hence, DEC was not a pathogen that was routinely detected in clinical laboratories especially in low and middle income countries [35, 36].…”

“…The reported infectious diarrhea is up to 70,000,000, and the reported incidence of infectious diarrhea is 55.9/10,000,000 annually in China listed by China Information System for Diseases Control and Prevention. Diarrheal illness incidence is located in top three of 39 notifiable infectious diseases [11, 16]. However, in many medical institutions, the lack of clinical microbiology laboratories and detection capabilities hamper the detection of etiological agents of gastroenteritis.…”

Etiological epidemiology of viral diarrhea on the basis of sentinel surveillance in children younger than 5 years in Gansu, northwest China, 2009-2013

“…The downward trend of isolation rate is consistent with the sentinel surveillance based study of bacterial pathogens‐induced diarrhea in Shanghai, China from 2006 to 2011. The reasons for this decline, albeit not well understood, may have important public health implications [Zhang et al, ].…”