Typhoid (typhoid fever)

Symptoms and clinical features

Onset is usually gradual with sustained fever. Other frequent features include headache, malaise, abdominal discomfort and changes in bowel habit. Characteristic signs that may help clinicians include:

• Prolonged high fever and weakness
• Abdominal pain, sometimes with constipation or diarrhea
• Small pink skin spots known as "rose spots" in some patients
• Complications in severe cases, such as intestinal bleeding or perforation, which require urgent care

Diagnosis relies on clinical assessment supported by laboratory tests: blood, stool or bone marrow cultures can identify the organism. Serologic tests exist but have limitations.

Transmission and prevention

Typhoid is transmitted by the fecal–oral route, most often through contaminated water or food handled by an infected person. Chronic carriers — people who continue to excrete the bacteria after recovery, sometimes for months or years — can sustain transmission. Preventive measures focus on:

• Safe water supply and improved sanitation
• Thorough handwashing and food hygiene
• Vaccination in endemic areas or for travelers to high‑risk regions

Treatment and public‑health importance

Appropriate antibiotic therapy shortens illness and prevents complications; choice of agent has evolved because resistance to older antibiotics has emerged. Supportive care, hydration and monitoring for complications are essential. Vaccines, including oral and injectable formulations, reduce the risk of disease and are part of control strategies in many countries. Public‑health measures — water treatment, sewage disposal and food safety — remain central to long‑term control.

History and distinctions

Typhoid has shaped public‑health policy for more than a century. The bacterium was identified in the late 19th century, and improvements in sanitation led to dramatic declines in incidence in wealthier nations. Notable historical episodes, including outbreaks and the description of chronic carriers, highlighted how asymptomatic individuals can spread disease.

Typhoid should not be confused with typhus, a distinct group of diseases caused by Rickettsia species, or with paratyphoid fever, which is clinically similar but usually caused by different Salmonella serovars. Understanding these differences helps guide diagnosis, treatment and preventive strategies.

Further information on the causative organism: see resources about Salmonella enterica for background on the bacterium and related infections.