Diarrhoea and Vomiting – Frequently Asked Questions
What causes diarrhoea and vomiting?
Diarrhoea and vomiting can be caused by a number of different organisms, including viruses, bacteria and parasites. These are usually contracted by eating contaminated food or drinking contaminated water, but some can be passed directly from person to person. The main symptoms are diarrhoea, vomiting, nausea, stomach pains and fever but these may vary.
The incubation period varies from a few hours up to 14 days depending upon agent, food consumed and number of organisms ingested.
All cases of gastro-enteritis should be regarded as potentially infectious. All persons in occupations or circumstances e.g. people working with food, where there is a special risk of spreading the illness should usually be excluded from work or school until they are well and have normal stools. Agents causing gastro-enteritis may infect without causing symptoms or be excreted for long periods after recovery, but transmission is unlikely providing that good personal hygiene is practised.
Precautions
Thorough hand washing and drying is the most important factor in preventing the spread of gastro-intestinal infections. This must be carried out after caring for people who are unwell, their bedding, clothing or sick room equipment and again before preparing or serving food.
Everyone must always wash their hands after using the toilet, and before meals. Towels must not be shared. If urinals and bedpans have to be used, the carer should, if possible, wear rubber or disposable gloves and must thoroughly wash hands after attending the patient. Where possible disposable latex or vinyl gloves should be used. If this is not possible designate a pair of household rubber gloves for this use only. Soiled clothing and bed linen should be washed in a domestic washing machine on a ‘hot’ cycle. If the amount of soiling makes this impractical, flush away as much faecal material as possible with running water into the toilet bowl. Rubber or disposable gloves should be worn and the hands must be thoroughly washed afterwards.
Toilet seats, flush handles, wash-hand basin taps and toilet door handles should be cleaned at least daily, using detergent, hot water and disposable cloths. More frequent cleaning may be needed depending on how often they are used. After visible soiling, wipe toilet seats with diluted hypochlorite/bleach disinfectant (1 part bleach to 10 parts water). These precautions are especially important in schools, nursery schools and residential institutions. Bedpans and urinals should be emptied into the toilet bowl and then washed with disinfectant and rinsed.
Everyone should be instructed in personal hygiene and in the hygiene of the preparation and serving of food. This teaching should be reinforced in those suffering from, or who are contacts of, patients with intestinal infections.
Social contact should be restricted especially with children, during the acute stage of the illness.
Some infections such as cryptosporidium cause mild but prolonged symptoms, and those affected may feel well enough to continue activities such as swimming. However they are still infectious to others. They should be excluded from work/school (see below), and in particular not use swimming pools, as outbreaks are often started in this way.
Food poisoning is a notifiable disease.
Food handlers and health care workers should be excluded from work whilst they are unwell, and until 48 hours after the return of their normal bowel habit.
Normal Incubation Periods for some Common Infections
- Campylobacter up to 10 days
- Cryptosporidium 1 – 12 days
- E coli O157 1 – 14 days
- Giardia 7 - 10 days
- Salmonella 6 - 72 hours
- Shigellosis (Bacillary dysentery) 1 - 7 days
