Typhoid fever is caused by Salmonella typhi bacteria. Typhoid fever is rare in developed countries. It is still a serious health threat in the developing world, especially for children.

Contaminated food and water or close contact with an infected person cause typhoid fever. Signs and symptoms usually include:

• High fever
• Headache
• Stomach pain
• Constipation or diarrhea

Most people who have typhoid fever feel better a few days after they start antibiotic treatment, but a small number of them may die of complications. Vaccines against typhoid fever are only partially effective. Vaccines usually are reserved for those who may be exposed to the disease or who are traveling to areas where typhoid fever is common.

Signs and symptoms are likely to develop gradually — often appearing one to three weeks after exposure to the disease.

Early illness

Signs and symptoms include:

• Fever that starts low and increases daily, possibly reaching as high as 104.9 F (40.5 C)
• Headache
• Weakness and fatigue
• Muscle aches
• Sweating
• Dry cough
• Loss of appetite and weight loss
• Stomach pain
• Diarrhea or constipation
• Rash
• Extremely swollen stomach

Later illness

Without treatment, you may:

• Become delirious
• Lie motionless and exhausted with your eyes half-closed in what's known as the typhoid state

Life-threatening complications often develop at this time.

In some people, signs and symptoms may return up to two weeks after the fever has subsided.

When to see a doctor

See a doctor immediately if you think you might have typhoid fever. If you live in the United States and become sick while traveling in a foreign country, call the U.S. Consulate for a list of doctors.

If you have signs and symptoms after you return home, consider seeing a doctor who focuses on international travel medicine or infectious diseases. A doctor who is familiar with these areas may be able to recognize and treat your illness more quickly.

Typhoid fever is caused by dangerous bacteria called Salmonella typhi. Salmonella typhi is related to the bacteria that cause salmonellosis, another serious intestinal infection, but they aren't the same.

Fecal-oral transmission route

Most people in developed countries pick up typhoid bacteria while they're traveling. Once they have been infected, they can spread it to others through the fecal-oral route.

This means that Salmonella typhi is passed in the feces and sometimes in the urine of infected people. If you eat food that has been handled by someone who has typhoid fever and who hasn't washed carefully after using the toilet, you can become infected.

In developing countries, where typhoid fever is established, most people become infected by drinking contaminated water. The bacteria may also spread through contaminated food and through direct contact with someone who is infected.

Typhoid carriers

Even after antibiotic treatment, a small number of people who recover from typhoid fever continue to harbor the bacteria. These people, known as chronic carriers, no longer have signs or symptoms of the disease themselves. However, they still shed the bacteria in their feces and are capable of infecting others.

Typhoid fever is a serious worldwide threat and affects about 27 million or more people each year. The disease is established in India, Southeast Asia, Africa, South America and many other areas.

Worldwide, children are at greatest risk of getting the disease, although they generally have milder symptoms than adults do.

If you live in a country where typhoid fever is rare, you're at increased risk if you:

• Work in or travel to areas where typhoid fever is established
• Work as a clinical microbiologist handling Salmonella typhi bacteria
• Have close contact with someone who is infected or has recently been infected with typhoid fever
• Drink water polluted by sewage that contains Salmonella typhi

Intestinal bleeding or holes

Intestinal bleeding or holes in the intestine are the most serious complications of typhoid fever. They usually develop in the third week of illness. In this condition, the small intestine or large bowel develops a hole. Contents from the intestine leak into the stomach and can cause severe stomach pain, nausea, vomiting and bloodstream infection (sepsis). This life-threatening complication requires immediate medical care.

Other, less common complications

Other possible complications include:

• Inflammation of the heart muscle (myocarditis)
• Inflammation of the lining of the heart and valves (endocarditis)
• Infection of major blood vessels (mycotic aneurysm)
• Pneumonia
• Inflammation of the pancreas (pancreatitis)
• Kidney or bladder infections
• Infection and inflammation of the membranes and fluid surrounding your brain and spinal cord (meningitis)
• Psychiatric problems, such as delirium, hallucinations and paranoid psychosis

With quick treatment, nearly all people in industrialized nations recover from typhoid fever. Without treatment, some people may not survive complications of the disease.

Safe drinking water, improved sanitation and adequate medical care can help prevent and control typhoid fever. Unfortunately, in many developing nations, these may be difficult to achieve. For this reason, some experts believe that vaccines are the best way to control typhoid fever.

A vaccine is recommended if you live in or are traveling to areas where the risk of getting typhoid fever is high.

Vaccines

Two vaccines are available.

• One is given as a single shot at least one week before travel.
• One is given orally in four capsules, with one capsule to be taken every other day.

Neither vaccine is 100% effective. Both require repeat immunizations because their effectiveness wears off over time.

Because the vaccine won't provide complete protection, follow these guidelines when traveling to high-risk areas:

• Wash your hands. Frequent hand-washing in hot, soapy water is the best way to control infection. Wash before eating or preparing food and after using the toilet. Carry an alcohol-based hand sanitizer for times when water isn't available.

• Avoid drinking untreated water. Contaminated drinking water is a particular problem in areas where typhoid fever is endemic. For that reason, drink only bottled water or canned or bottled carbonated beverages, wine and beer. Carbonated bottled water is safer than non-carbonated bottled water.

  Ask for drinks without ice. Use bottled water to brush your teeth, and try not to swallow water in the shower.

• Avoid raw fruits and vegetables. Because raw produce may have been washed in contaminated water, avoid fruits and vegetables that you can't peel, especially lettuce. To be absolutely safe, you may want to avoid raw foods entirely.
• Choose hot foods. Avoid food that's stored or served at room temperature. Steaming hot foods are best. And although there's no guarantee that meals served at the finest restaurants are safe, it's best to avoid food from street vendors — it's more likely to be infected.
• Know where the doctors are. Find out in advance about medical care in the areas you'll visit, and carry a list of the names, addresses and phone numbers of recommended doctors.

Prevent infecting others

If you're recovering from typhoid fever, these measures can help keep others safe:

• Take your antibiotics. Follow your doctor's instructions for taking your antibiotics, and be sure to finish the entire prescription.
• Wash your hands often. This is the single most important thing you can do to keep from spreading the infection to others. Use hot, soapy water and scrub thoroughly for at least 30 seconds, especially before eating and after using the toilet.
• Avoid handling food. Avoid preparing food for others until your doctor says you're no longer contagious. If you work in the food service industry or a health care facility, you won't be allowed to return to work until tests show that you're no longer shedding typhoid bacteria.

Medical and travel history

Your doctor is likely to suspect typhoid fever based on your symptoms and your medical and travel history. The diagnosis is usually confirmed by identifying Salmonella typhi in a culture of your blood or other body fluid or tissue.

Body fluid or tissue culture

For the culture, a small sample of your blood, stool, urine or bone marrow is placed on a special medium that encourages the growth of bacteria. The culture is checked under a microscope for the presence of typhoid bacteria. A bone marrow culture often is the most sensitive test for Salmonella typhi.

Although performing a culture test is the most common diagnostic test, other testing may be used to confirm a suspected typhoid fever infection, such as a test to detect antibodies to typhoid bacteria in your blood, or a test that checks for typhoid DNA in your blood.

Antibiotic therapy is the only effective treatment for typhoid fever.

Commonly prescribed antibiotics

Commonly prescribed antibiotics include:

• Ciprofloxacin (Cipro). In the United States, doctors often prescribe this for adults who aren't pregnant. Another similar drug called ofloxacin also may be used. Unfortunately, many Salmonella typhi bacteria are no longer susceptible to antibiotics of this type, particularly strains picked up in Southeast Asia.
• Azithromycin (Zithromax). This may be used if a person is unable to take ciprofloxacin or the bacteria are resistant to ciprofloxacin.
• Ceftriaxone. This injectable antibiotic is an alternative in more-complicated or serious infections and for people who may not be candidates for ciprofloxacin, such as children.

These drugs can cause side effects, and long-term use can lead to the development of antibiotic-resistant bacteria.

Problems with antibiotic resistance

In the past, the drug of choice was chloramphenicol. Doctors no longer commonly use it because of side effects, a high rate of health deterioration after a period of improvement (relapse) and widespread bacterial resistance.

In fact, antibiotic-resistant bacteria are becoming more common, especially in the developing world. In recent years, Salmonella typhi has also proved resistant to trimethoprim-sulfamethoxazole, ampicillin and ciprofloxacin.

Other treatments

Other treatments include:

• Drinking fluids. This helps prevent the dehydration that results from a prolonged fever and diarrhea. If you're severely dehydrated, you may need to receive fluids through a vein (intravenously).
• Surgery. If your intestines become torn, you'll need surgery to repair the hole.

Call your doctor if you've recently returned from travel abroad and develop mild symptoms similar to those that occur with typhoid fever. If your symptoms are severe, go to an emergency room or call 911 or your local emergency number.

Here's some information to help you get ready and know what to expect from your doctor.

Information to gather in advance

• Pre-appointment restrictions. At the time you make your appointment, ask if there are restrictions you need to follow in the time leading up to your visit. Your doctor will not be able to confirm typhoid fever without a blood test, and may recommend taking steps to reduce the risk of passing a possible contagious illness to others.
• Symptom history. Write down any symptoms you're experiencing and for how long.
• Recent exposure to possible sources of infection. Be prepared to describe international trips in detail, including the countries you visited and the dates you traveled.
• Medical history. Make a list of your key medical information, including other conditions for which you're being treated and any medications, vitamins or supplements you're taking. Your doctor will also need to know your vaccination history.
• Questions to ask your doctor. Write down your questions in advance so that you can make the most of your time with your doctor.

For typhoid fever, possible questions to ask your doctor include:

• What are the possible causes for my symptoms?
• What kinds of tests do I need?
• Are treatments available to help me recover?
• I have other health problems. How can I best manage these conditions together?
• How long do you expect a full recovery will take?
• When can I return to work or school?
• Am I at risk of any long-term complications from typhoid fever?

Don't hesitate to ask any other related questions you have.

What to expect from your doctor

Your doctor is likely to ask you a number of questions. Being ready to answer them may reserve time to go over any points you want to talk about in-depth. Your doctor may ask:

• What are your symptoms and when did they begin?
• Have your symptoms gotten better or worse?
• Did your symptoms briefly get better and then come back?
• Have you recently traveled abroad? Where?
• Did you update your vaccinations before traveling?
• Are you being treated for any other medical conditions?
• Are you currently taking any medications?