Epidemiologic Characteristics of Foodborne Outbreaks in Southern Vietnam, 2009–2013

Abstract

Introduction: Accurate data on the burden of foodborne diseases (FBD) are important to inform prevention and control measures. We described epidemiologic characteristics and assessed trends in foodborne outbreaks in Southern Vietnam. Methodology: We analyzed surveillance data of outbreaks reported in Southern Vietnam during 2009–2013. A FBD outbreak is defined as “two or more people who got gastrointestinal disorder after eating the same meal or one fatal case after eating a meal”. Annual rates of outbreaks/100,000 population were calculated; trends in outbreaks were assessed in time-series analysis. Results: During 2009-2013, there were 261 reported outbreaks, 10,263 cases, and 50 deaths; rate, 0.16 outbreaks/100,000 population/year. Of all outbreaks, 77% occurred in nine provinces (population 19.4 million) where export manufacturing zones are located (2–8 outbreaks/province/year). Of 212 outbreaks in which reporters had suspected an etiology, bacteria accounted for 41%, natural toxins for 20%, and unknown causes for 28%. Seventytwo percent of all cases were associated with meals eaten in canteens; 94% of cases lived in the nine provinces. Four percent of all cases were linked to family meals; 85% of these cases lived in the rural Mekong Delta region. All 50 fatal cases were attributed to toxic chemicals or natural toxins, 48 were family meals. Most outbreaks occurred in warmer months, but no temporal trend was seen in reported outbreaks. Conclusions: The rate of reported outbreaks and total reported cases of FBD were low, suggesting underdetection and underreporting. Most identified outbreaks were associated with meals eaten in canteens; fatal cases were linked to family meals. J Microbiol Infect Dis 2017; 7(1): 13-20