A persistent high fever, headache, fatigue, and abdominal pain may seem like symptoms of a common infection. However, in some cases, they may be signs of “typhoid fever” (Typhoid Fever), a bacterial infection that can lead to serious complications if not properly treated.

Typhoid fever is mainly associated with consuming food or water contaminated with the bacteria. It is more common in areas with limited access to clean water and adequate sanitation. People traveling to areas where typhoid fever is common should pay particular attention to food and water hygiene and consider vaccination based on medical advice.

What Is Typhoid Fever?

Typhoid fever (Typhoid Fever) is an infectious disease caused by the bacterium Salmonella enterica serovar Typhi, or Salmonella Typhi. The bacterium lives only in humans and can spread through food or water contaminated with the feces of an infected person or carrier.

After entering the body, the bacteria can multiply in the gastrointestinal tract before spreading into the bloodstream and affecting other parts of the body. This can cause a persistent fever and other systemic symptoms.

Typhoid fever is different from some other Salmonella infections that commonly cause food poisoning. Salmonella Typhi can cause a systemic infection and may lead to serious complications.

Why Is Typhoid Fever Important?

According to the World Health Organization (WHO), an estimated 9 million people developed typhoid fever in 2019, with approximately 110,000 deaths worldwide. The disease remains an important public health concern, particularly in areas with limited access to safe drinking water and adequate sanitation.

Another growing concern is the increasing resistance of Salmonella Typhi to antibiotics in several regions. This can make treatment more complicated. People who may have typhoid fever should therefore avoid self-medicating with antibiotics and seek appropriate medical evaluation and treatment.

How Does Typhoid Fever Spread?

Typhoid fever is primarily transmitted through contaminated food and water. Factors that may increase the risk of infection include:

• Drinking unsafe or contaminated water
• Eating undercooked food or food prepared under unhygienic conditions
• Eating raw fruits or vegetables washed with contaminated water
• Not washing hands properly after using the toilet or before preparing or eating food
• Living in or traveling to areas where typhoid fever is common and sanitation is inadequate
• Eating food handled by an infected person or someone who continues to carry the bacteria

Even after symptoms have resolved, some people may continue to carry Salmonella Typhi and shed the bacteria in their stool. Follow-up testing may therefore be necessary based on a doctor’s recommendation.

Symptoms of Typhoid Fever

Symptoms of typhoid fever may develop gradually and can vary from person to person. Common symptoms include:

• Persistent high fever, which may reach approximately 39–40°C
• Headache
• Fatigue and weakness
• Abdominal pain
• Loss of appetite
• Nausea or vomiting
• Constipation or diarrhea
• Cough in some patients
• Muscle or body aches
• Faint pink spots on the trunk in some patients

These symptoms can resemble those of many other infections. Therefore, symptoms alone cannot confirm a diagnosis of typhoid fever.

When Should You Seek Urgent Medical Attention?

Typhoid fever can cause serious complications, particularly when appropriate treatment is delayed. Anyone with a persistent high fever and significant illness should seek medical evaluation.

Seek urgent medical attention if symptoms include:

• Severe or rapidly worsening abdominal pain
• A rigid abdomen or significant abdominal tenderness
• Gastrointestinal bleeding, such as bloody or black stools
• Persistent vomiting or inability to drink or eat
• Confusion, unusual drowsiness, or changes in consciousness
• Signs of severe dehydration
• Rapid deterioration in overall condition

How Is Typhoid Fever Diagnosed?

Because typhoid fever can resemble many other infectious diseases, doctors may begin by asking about symptoms, how long the fever has been present, recent food consumption, and travel history, particularly travel to areas where typhoid fever is common.

An important laboratory test is a blood culture, which can be used to detect Salmonella Typhi. In some cases, doctors may collect other samples depending on the patient’s condition and clinical circumstances.

Antibiotic susceptibility testing may also be important because antibiotic-resistant strains of Salmonella Typhi have become increasingly common in some regions. The results can help doctors select an appropriate antibiotic.

How Is Typhoid Fever Treated?

The main treatment for typhoid fever is antibiotic therapy. The choice of antibiotic depends on factors such as the patient’s condition, travel history, severity of the infection, and local patterns of antibiotic resistance.

Patients should take antibiotics exactly as prescribed and complete the full course, even if they begin to feel better. Antibiotics should not be stopped, changed, or taken without medical advice, as inappropriate use can lead to treatment failure and contribute to antibiotic resistance.

Patients with severe illness, complications, or an inability to eat or drink may require hospitalization.

After treatment, some patients may continue to carry the bacteria even after their symptoms have resolved. Doctors may therefore recommend follow-up testing, particularly for people who work with food, care for patients, or have close contact with young children.

How to Take Care of Yourself During Treatment

In addition to taking prescribed medications, appropriate self-care can support recovery and reduce the risk of spreading the infection to others:

• Getting adequate rest
• Drinking enough fluids to prevent dehydration
• Eating clean, properly cooked food
• Washing hands thoroughly with soap and water after using the toilet
• Completing the full course of antibiotics prescribed by your doctor
• Avoiding preparing or serving food to others while you may still be infectious
• Attending follow-up appointments, particularly if your doctor recommends testing to determine whether you are still carrying the bacteria
• If symptoms return after treatment, consult a doctor for further evaluation

How Can Typhoid Fever Be Prevented?

Prevention focuses on reducing exposure to Salmonella Typhi through contaminated food and water, especially when traveling to areas where typhoid fever is common.

• Choose safe food: Eat food that is thoroughly cooked and served hot. Avoid raw or undercooked food and food prepared under questionable hygienic conditions.
• Drink safe water: In areas where water quality is uncertain, choose sealed bottled water or water that has been appropriately treated. Be cautious with ice if the source of the water is unknown.
• Wash your hands regularly: Wash your hands thoroughly with soap and water before eating or preparing food and after using the toilet.
• Be careful with raw fruits and vegetables: Wash fruits and vegetables with safe water. When traveling in high-risk areas, consider choosing fruits that you can peel yourself.
• Consider typhoid vaccination: Typhoid vaccines can help reduce the risk of infection, particularly for people traveling to areas where the disease is common. However, vaccination does not provide 100% protection, so food, water, and personal hygiene precautions remain important.

People planning international travel can consult a doctor or travel medicine clinic to determine whether typhoid vaccination is appropriate based on their destination, age, medical history, and the vaccines available.

Who Should See a Doctor?

You should consult a doctor if you have symptoms that may suggest typhoid fever, particularly if:

• You have a persistent high fever lasting several days
• You have a fever accompanied by abdominal pain, diarrhea, or unusual constipation
• You develop a fever after returning from an area where typhoid fever is common
• You may have consumed contaminated food or water
• Your symptoms do not improve or become more severe
• You are a young child, older adult, pregnant, or have an underlying medical condition
• You have previously been treated for typhoid fever and your symptoms return
• You work in food preparation, healthcare, or childcare and have been diagnosed with typhoid fever

If typhoid fever is suspected, tell your doctor about your recent travel history and the places you have visited, as this information may help with diagnosis and treatment decisions.

Summary

Typhoid fever is a bacterial infection caused by Salmonella Typhi and is mainly transmitted through contaminated food or water. Common symptoms include persistent high fever, fatigue, headache, abdominal pain, diarrhea, or constipation. Without appropriate treatment, the infection can lead to serious complications.

The main treatment is antibiotics selected by a doctor according to the patient’s condition and antibiotic resistance patterns. The risk of infection can be reduced by consuming safe food and water, maintaining good hand hygiene, and considering typhoid vaccination when appropriate or before traveling to high-risk areas.

If you develop a persistent high fever, particularly after traveling to an area where typhoid fever is common, avoid self-diagnosis or self-treatment with antibiotics. Seek medical attention for appropriate testing and treatment.

Prepared by: Punyanooch Angkanawin, Pharmacist

References

1. World Health Organization (WHO). Typhoid
2. Centers for Disease Control and Prevention (CDC). Clinical Guidance for Typhoid Fever and Paratyphoid Fever
3. National Health Service (NHS). Typhoid fever