Detection of Enteric Bacteria in Raw Food Samples from Vietnam ...

1.1.4.1.3. Salmonella spp. disease and treatment
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CHAPTER 1: INTRODUCTION
Strains of nontyphoidal Salmonella usually cause an intestinal infection with the symptoms of
diarrhoea, vomiting, chills and headache. The associated dehydration can become severe and
life-threatening particularly in the very young and in the elderly. Less commonly,
nontyphoidal Salmonella can cause localised infections such as osteomyelitis or urinary tract
infections (Hohmann, 2001; Bopp et al., 2003). Although Salmonella spp. gastroenteritis is
generally a self-limiting illness that may require fluid and electrolyte replacement, antibiotics
are needed in severe cases. Fluoroquinolones are the antimicrobials most widely regarded as
optimal for the treatment of salmonellosis in adults. Third-generation cephalosporins are
widely used in children with serious infections. The earlier drugs chloramphenicol, ampicillin
and amoxicillin and trimethoprim-sulfamethoxazole could be used as alternatives for
salmonellosis treatment (Hohmann, 2001; WHO, 2005b).
1.1.4.2. Diseases and symptoms caused by diarrhoeagenic E. coli
E. coli is a common flora organism in the gastrointestinal tract of humans and animals. Most
of them are harmless; however, some are pathogenic and can cause disease. Diarrhoeagenic
E. coli is the most commonly bacterial cause of childhood diarrhoea in Vietnam (Nguyen et
al., 2005b; Nguyen et al., 2006). Diarrhoeagenic E. coli strains are categorised into specific
groups based on virulence properties, mechanisms of pathogenicity, clinical syndromes, and
distinct O:H serotypes (Meng et al., 2001). The six main categories include enteropathogenic
E. coli (EPEC), enterotoxigenic E. coli (ETEC), enteroinvasive E. coli (EIEC),
enteroaggregative E. coli (EAEC), enterohemorrhagic E. coli (EHEC), diffuse-adhering E.
coli (DAEC) (Nataro and Kaper, 1998a). Other diarrhoeagenic E. coli pathotypes have been