Typhoid is a systemic disease caused by Salmonella Typhi bacteria and transmitted by the faecal-oral route (eating contaminated food, or drinking contaminated water). Paratyphoid is a similar infection caused by Salmonella Paratyphi A, B or C bacteria usually causing milder symptoms. Collectively typhoid and paratyphoid are referred to as enteric fever.
Typhoid is a travel related hazard for those visiting endemic areas overseas and nurses practising travel health play a key role in preventing typhoid infection by offering advice on prevention.
This article provides an overview of typhoid with a focus on overseas travellers.
Transmission of typhoid
Salmonella Typhi bacteria can be excreted in the faeces of patients who are acutely unwell with typhoid or who are chronic carriers of the disease. Transmission then occurs by ingesting the bacteria, usually via food or water that has been contaminated with faeces as a result of poor food hygiene or sanitation.
Direct transmission can occur as a result of eating raw vegetables fertilised with human waste (a common practice in some countries), or via shellfish harvested from sewage-contaminated waters. Food prepared by an individual excreting the bacteria can be contaminated if they have not taken adequate hygiene precaution. Severity of illness varies depending on how many bacteria are ingested.