Factsheet

Typhoid

Typhoid fever is caused by an infection with bacteria called Salmonella Typhi. In Australia, most typhoid infections are acquired overseas by individuals eating contaminated food or water while visiting friends and relatives in developing countries. Typhoid vaccination is strongly recommended for travellers to developing countries.

Last updated: 07 July 2011

What is typhoid and paratyphoid fever?

Typhoid fever is a disease caused by the bacteria Salmonella Typhi. Paratyphoid fever is a disease caused by the bacteria Salmonella Paratyphi. These diseases cause a similar illness. Paratyphoid infections tend to be less severe and less common than typhoid.

In Australia, most typhoid and paratyphoid infections are acquired overseas by individuals eating contaminated food or water in developing countries while visiting friends and relatives or travelling. These infections are different to infection with Salmonella which usually causes gastroenteritis.

What are the symptoms?

People with typhoid or paratyphoid fever may experience mild or severe symptoms. The symptoms may include fever, headache, general discomfort and a lack of appetite. Some people have rose spots on the trunk of the body. Constipation or diarrhoea may occur. For typhoid fever, symptoms generally start 8 to 14 days following infection but possibly as early as 3 days or as late as over 60 days after infection. For paratyphoid fever, gastroenteritis may start 1 to 10 days following infection. Some people do not have any symptoms.

How is it spread?

The bacteria that cause typhoid and paratyphoid fever are found in the faeces of infected individuals. Some people (known as carriers) continue to carry the bacteria even after symptoms have resolved. Transmission usually occurs when faecally-contaminated food and water are ingested. Therefore, typhoid fever is more common in less developed countries with poor sanitation, poor hand hygiene and food handling standards, and untreated drinking water. Raw fruits and vegetables and shellfish are the types of foods most often associated with illness. Flies may transfer the bacteria to food.

Who is at risk?

Typhoid fever is widespread in most parts of the world except for the developed regions. In Australia, typhoid and paratyphoid fever almost always occur in overseas travellers. Immigrants who return to developing countries (in particular India, Pakistan and Bangladesh) to visit friends and relatives are at greatest risk of acquiring the disease.
People who have travelled or live with an infected person will be screened for typhoid fever by their local public health unit.
Household contacts, or people who have travelled with a person infected with typhoid, will be screened for typhoid by their local public health unit. Contacts should be aware of the symptoms of typhoid and should see their general practitioner if they develop symptoms.

How is it prevented?

People travelling to countries where typhoid and paratyphoid fever are common should:

receive the typhoid vaccine two weeks prior to travel (for those ≥ 2 years). Typhoid vaccination is required every three years to protect from infection.
wash hands thoroughly with soap and water after going to the toilet and before eating
avoid uncooked foods, including fruit and vegetables unless you are able to be peal them yourself
drink bottled or boiled water
not drink untreated water, including ice and drinks mixed with water
avoid eating from street stalls
ensure hot food is thoroughly cooked and eaten whilst hot.

People infected with typhoid or paratyphoid fever, or who share a house with someone infected with typhoid, MUST NOT work if their work involves food handling or caring for children, patients or the elderly, and should not prepare food for others until stool samples have shown that they are not infectious. A number of stool tests will be required to assess when you are no longer infected. Your local public health unit will advise you when are able to return to work.

How is it diagnosed?

To diagnose typhoid and paratyphoid fever, your general practitioner or local hospital will send a blood or stool sample to a laboratory for testing.

How is it treated?

Typhoid or paratyphoid fever is treated with antibiotics. Some people may never have symptoms but may be carriers of typhoid or paratyphoid. Antibiotic treatment is required to treat carriers also.

If symptoms are severe, hospitalisation may be required.

What is the public health response?

Public health unit staff will interview the doctor or patient (or carers) to find out how the infection occurred.
The NSW Food Authority, in collaboration with NSW Health, is responsible for the environmental investigation of food handlers with typhoid oe paratyphoid fever.
Your local public health unit can advise further regarding exclusions from work and school. People excluded from work will need to have a number of stool tests done before they are allowed to return to work.