normally prefers to colonize the nasopharynx and the small intestine (esp. in those with decreased gastric acid secretion it seems) with later colonization of the large bowel however antibiotic Rx can disturb this colonization and result in dissemination to other tissues, while the capsule polysaccharide is necessary for the colonization of the large intestine. Gut colonization is a requesite for infection elsewhere.
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