Distribution of Salmonella Serovars in Humans, Foods, Farm Animals and Environment, Companion and Wildlife Animals in Singapore

Abstract

We analyzed the epidemiological distribution of <i>Salmonella</i> serovars in humans, foods, animals and the environment as a One-Health step towards identifying risk factors for human salmonellosis. Throughout the 2012-2016 period, <i>Salmonella</i> ser. Enteritidis was consistently the predominating serovar attributing to >20.0% of isolates in humans. Other most common serovars in humans include <i>Salmonella</i> ser. Stanley, <i>Salmonella</i> ser. Weltevreden, <i>Salmonella</i> ser. Typhimurium and <i>Salmonella</i> ser. 4,5,12:b:-(dT+). <i>S.</i> Enteritidis was also the most frequent serovar found among the isolates from chicken/chicken products (28.5%) and eggs/egg products (61.5%) during the same period. In contrast, <i>S.</i> Typhimurium (35.2%) and <i>Salmonella</i> ser. Derby (18.8%) were prevalent in pork/pork products. <i>S</i>. Weltevreden was more frequent in seafood (19.2%) than others (≤3.0%). Most isolates (>80.0%) from farms, companion and wildlife animals belonged to serovars other than <i>S</i>. Enteritidis or <i>S</i>. Typhimurium. Findings demonstrate the significance of a One-Health investigative approach to understand the epidemiology <i>Salmonella</i> for more effective and integrated surveillance systems.