Faecal specimens should be collected in the early stages of a disease, before antibiotic treatment is started, when pathogens are likely to be present in the stool in high numbers. Stool specimens should be collected in a sterile container of appropriate size with a tight-fitting, leakproof lid. The collected stool should be processed as soon as possible upon receipt in the laboratory, and no longer than 2 hours after collection. If it is not possible to process the specimen within 2 hours, a small amount should be collected on a swab inserted into the stool and rotated. This should then be inoculated into a suitable transport medium, together with any mucus and shreds of epithelium present. Cary-Blair transport medium is appropriate for all enteric pathogens; alkaline peptone water is suitable for Vibrio spp.