Topic: Typhoid and Paratyphoid Fever
Description
Typhoid and paratyphoid fever are diseases of the intestinal tract caused by the Salmonella Typhi and Salmonella paratyphi bacteria. Typhoid is rare in developed countries. However, where environmental hygiene is poor, as in many developing countries, typhoid is a major public health problem. The greatest risk exists to travellers visiting countries where the disease is common. In Queensland, approximately 10 cases of typhoid are notified each year, most occurring in returned overseas travellers.
Symptoms
The symptoms of typhoid fever may be mild or severe and may include sustained fever, severe headache, constipation or diarrhoea, rose-coloured spots on the trunk and an enlarged spleen and liver. Most people usually recover fully over several weeks, although typhoid can be fatal if untreated. Relapses are common and occur in up to 20% of cases.
The time from contact with the bacteria and the onset of symptoms is usually 8 - 14 days but can be longer.
Transmission
Typhoid is usually spread when faeces or urine from an infected person contaminates something that is transferred to another person's mouth. Contaminated water and food are the most common sources of infection. Flies may also spread the bacteria to food products.
A person is infectious for as long as the bacteria is present in the faeces or urine and usually extends from the first week of symptoms, and continuing throughout the recovery period. About 10% of untreated typhoid cases can be infectious for three months after the onset of symptoms, and in some countries 1% to 5% become permanent carriers.
Treatment
Antibiotics are usually used for the treatment of typhoid and paratyphoid.
Prevention
Because the bacteria is passed in the faeces and urine of infected people, good hygiene is the single most effective way of preventing the spread of the disease. Hands should be washed thoroughly in soap and water for at least 15 seconds and then dried thoroughly. It is important to wash hands after going to the toilet, touching soiled linen or articles and before preparing or eating food.
Overseas travellers visiting high risk areas should avoid ingesting potentially contaminated water and food. This can be achieved by only consuming bottled water (even when brushing teeth) and avoiding ice in drinks.
Typhoid vaccination is only recommended for travellers at risk, i.e. those travelling to endemic countries where hygiene is poor or drinking water is unsafe. Vaccination is no longer a legal requirement for entry into any country. However the longer the stay in an endemic area the more important it is to be vaccinated.
Control
Cases and contacts at high risk of transmission of the disease include food handlers, those caring for patients, children, the elderly and those unable to maintain personal hygiene. These cases should be excluded from work, school, child care and from public swimming pools until they receive a medical certificate of recovery following the receipt of negative stool tests.
Cases and contacts at low risk of transmission may return to work or school when they have recovered and have not had a loose bowel action for 24 hours.
Contacts of a confirmed case include all people who live in the same household, or if the disease was acquired overseas, travel companions.
Good hygiene is the single most effective way of preventing the spread of the disease. The importance of effective hand washing, especially after using the toilet and before preparing or handling food, must be emphasised.
Typhoid and paratyphoid are notifiable conditions in Queensland. Population health authorities will assist with the follow up of cases and contacts to ensure that they are no longer a risk for spreading the disease to other people.
Help and Assistance
For further information, please contact your local doctor, community health centre or nearest Population Health Unit or contact Queensland Health information phone number 13HEALTH.
Other Resources
Footnotes
Heymann, D., ed. 2004. Control of Communicable Diseases Manual, 18th edition. Washington, DC: American Public Health Association.
National Health and Medical Research Council, 2003. The Australian Immunisation Handbook (8th Ed.) Canberra: National Capital Printing.
Last Updated: 12th October, 2009
Date Valid to: 30th June, 2010
