Full-size Left-side Hidden
EPIDEMIOLOGICAL ASPECTS

The prevalence of different enteropathogens varies with the age of the individual, how the diarrhoea is acquired (e.g. food poisoning or traveller's diarrhoea), between acute and chronic diarrhoea, and with the state of the host's immunity (Table 50.2).

Age

In general, paediatric diarrhoea is most often due to viral enteropathogens (see  Chapter 45). Up to 60% of cases in most hospital-based surveys are due to viruses, with rotavirus accounting for a large proportion of cases, followed by adenovirus 40/41 and then astrovirus, but it is now clear that noroviruses are important causes of outbreaks of disease. Bacterial enteropathogens such as enteropathogenic Escherichia coli (EPEC), enteroinvasive E. coli (EIEC), enterotoxigenic E. coli (ETEC), enteroaggregative E. coli (EAggEC), salmonellae, Campylobacter jejuni and shigellae and the protozoan Cryptosporidium parvum and C. hominis are responsible for the majority of the remaining cases where a pathogen is found.

In …