Typhoid Fever

How typhoid spreads

Humans are the only natural host of S. Typhi. It spreads by the fecal-oral route:

• drinking water contaminated with sewage
• eating food prepared by someone who carries the bacteria and has not washed their hands
• raw fruits and vegetables washed in contaminated water
• ice, street food and drinks in areas with poor sanitation

About 1 to 5 percent of people become chronic carriers after infection, often harboring bacteria in the gallbladder, and can spread it without symptoms.

Symptoms

The incubation period is usually 6 to 30 days. Symptoms often develop gradually:

Week 1

• Fever that rises step by step, reaching 39 to 40 °C (102 to 104 °F)
• Headache, weakness and tiredness
• Dry cough
• Loss of appetite
• Belly pain, constipation (common in adults) or diarrhea (more common in children)

Week 2

• Persistent high fever
• A relatively slow pulse for the degree of fever, in some
• Rose spots: faint, flat, pink spots on the chest and belly in some people
• Enlarged liver and spleen
• Increasing weakness, sometimes confusion

Week 3 and beyond

Without treatment, serious complications can develop, including intestinal bleeding and intestinal perforation, sepsis, and inflammation of the heart, brain or other organs.

Paratyphoid fever, caused by Salmonella Paratyphi, causes a similar but usually milder illness. Together they are called enteric fever. See paratyphoid fever.

Typhoid vs other causes of fever after travel

Diagnosis

• Blood cultures: the main test, most positive in the first week.
• Stool and urine cultures, more often positive later in the illness.
• Bone marrow culture: the most sensitive test, used when others are negative.
• Susceptibility testing: essential because of rising antibiotic resistance.
• Rapid antibody tests (such as the Widal test) are unreliable and should not be used alone.
• Tests for malaria and other causes of fever in travelers.

Treatment

• Antibiotics: the choice depends on where the infection was acquired and resistance testing. Options include azithromycin, ceftriaxone, and for extensively drug-resistant (XDR) typhoid, such as strains from Pakistan, carbapenems. Fluoroquinolone resistance is widespread, especially in South Asia.
• Hospital care for severe illness, vomiting, dehydration or complications.
• Fluids and nutrition.
• Fever control: acetaminophen (paracetamol) at the label dose.
• Surgery for intestinal perforation.
• Follow-up stool tests for food handlers, healthcare workers and childcare workers before returning to work.
• Chronic carriers may need prolonged antibiotics and sometimes gallbladder removal.

Outlook

With prompt, appropriate antibiotics, most people improve within 3 to 5 days and recover fully, though fatigue may last weeks. Relapse occurs in a small percentage. Untreated typhoid can be fatal in a significant proportion of cases, mainly from complications.

Prevention

Vaccination

The CDC recommends typhoid vaccination for travelers to areas where typhoid is common:

• Injectable vaccine (Vi polysaccharide): a single shot at least 2 weeks before travel. Booster every 2 years if risk continues.
• Oral vaccine (Ty21a): capsules taken over a week, finishing at least 1 week before travel. Booster every 5 years.

Vaccines are about 50 to 80 percent effective, so food and water precautions remain important.

Food and water safety

• Drink bottled, boiled or treated water. Avoid ice unless made from safe water.
• Eat food that is freshly cooked and served hot.
• Avoid raw vegetables and fruits you have not peeled yourself.
• Avoid food and drinks from street vendors.
• Wash hands with soap often, especially before eating and after using the toilet.

Frequently asked questions

What are the first symptoms of typhoid fever?

Early symptoms include a fever that rises gradually over several days, headache, weakness, loss of appetite and belly pain. Adults often have constipation, while children more often have diarrhea. Anyone with fever after travel to a high-risk area should see a doctor promptly.

How is typhoid spread?

Typhoid spreads through food or water contaminated with feces from an infected person or carrier. Contaminated drinking water, ice, raw produce and food prepared by someone with unwashed hands are common sources. It is most common in areas with poor sanitation.

Is typhoid curable?

Yes. Typhoid is curable with the right antibiotics, and most people improve within a few days of starting treatment. Rising antibiotic resistance makes testing and choosing the correct antibiotic important. Untreated typhoid can lead to serious complications.

How long does the typhoid vaccine last?

The injectable typhoid vaccine protects for about 2 years, and the oral vaccine for about 5 years. Neither is 100 percent effective, so travelers should also follow safe food and water practices.