Typhoid is a bacterial infection that can lead to a high fever, diarrhea, and vomiting. It is caused by the bacterium Salmonella typhimurium (S. typhi). If a doctor catches it early, they can treat it with antibiotics. Otherwise, typhoid can be fatal.

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A person typically contracts typhoid through contaminated food and drinking water. It may also pass from person to person by carriers who do not know they carry the bacteria.

Typhoid is more prevalent in places with less efficient sanitation and hygiene.

The Centers for Disease Control and Prevention (CDC) estimate that there are around 5,700 cases of typhoid in the United States every year. Most people receive a diagnosis after traveling internationally, meaning they likely contract it abroad.

Globally, 11–20 million people per year contract typhoid.

Here are some key points about typhoid. More detail is in the main article.

  • Untreated, typhoid is fatal in around 10–30% of cases.
  • Symptoms include a high fever and gastrointestinal (GI) issues.
  • Some people carry the bacteria without developing symptoms.
  • Most cases reported in the U.S. are contracted overseas.
  • The only treatment for typhoid is antibiotics.

Typhoid is an infection caused by the bacterium S. typhi.

The bacterium lives in the intestines and bloodstream of humans. It spreads between individuals through direct contact with the feces of a person with an infection.

No animals carry this disease, so transmission is always from human to human. S. typhi enters through the mouth and spends 1–3 weeks in the intestine. Then, it makes its way through the intestinal wall and into the bloodstream.

From the bloodstream, it spreads into other tissues and organs. The immune system of the host can do little to fight back, because S. typhi can live within the host’s cells, safe from the immune system.

Doctors diagnose typhoid by detecting the presence of S. typhi via blood, stool, urine, or bone marrow sample.

Symptoms typically begin 1–3 weeks after exposure to the bacteria.

The two main symptoms of typhoid are fever and rash. Typhoid fever is particularly high, gradually increasing over several days up to 104ºF.

The rash, which does not affect every person, consists of rose-colored spots, particularly on the neck and abdomen.

Other symptoms can include:

Typhoid is caused by the bacteria S. typhi. It spreads through food, drinks, and drinking water that are contaminated with infected fecal matter. Washing fruit and vegetables can spread it as well if the water is contaminated.

Some people have typhoid without experiencing any symptoms. Others continue to harbor the bacteria after their symptoms have gone. Sometimes, the disease can appear again.

People who test positive for typhoid may not be allowed to work with children or older adults until medical tests are negative.

Typhoid fever is most prevalent in South Asia, Southeast Asia, and sub-Saharan Africa.

People who live or work in or travel to places where typhoid infections are common are at risk of contracting the bacterium.

In countries not known for many typhoid fever infections, outbreaks can still happen in areas where sanitation and hygiene are insufficient.

In the U.S., there are about 500 cases of typhoid fever per year, and more than half of these come from infections people contracted abroad.

However, local outbreaks tend to happen in the food industry, where a person who carries the virus transmits it via food. Although this is rare, people who work in restaurants or other food-related businesses may be more at risk.

A doctor will typically diagnose typhoid fever based on a person’s specific history in order to differentiate it from paratyphoid, which is an infection caused by Salmonella enterica. This infection has similar symptoms to typhoid, but it is less likely to be fatal.

A doctor will ask a person questions about whether they have traveled or lived in areas where the disease is endemic or where there have been known outbreaks.

They will also want to know whether the person has received relevant vaccination, where and how they live, and whether they have been taking any medications. They may also want to know whether the person has come into contact with unclean food or water.

The only effective treatment for typhoid is antibiotics. Doctors most commonly use ciprofloxacin (Cipro) for nonpregnant people.

Other antibiotics a doctor may use are:

  • chloramphenicol (Chloromycetin)
  • ampicillin (Ampi, Omnipen, Penglobe, and Principen)
  • sulfamethoxazole/trimethoprim (Bactrim)

Pregnant people should also avoid chloramphenicol.

A person with typhoid needs to rehydrate by drinking adequate amounts of water. In more severe cases, where the bowel has become perforated, a person may need surgery.

However, as with a number of other bacterial conditions, there is concern about the growing resistance of antibiotics to S. typhi.

There have been outbreaks of multidrug-resistant typhoid strains, such as the outbreak in Pakistan in 2018, in which patients were resistant to five different antibiotic types.

For this reason, the CDC recommends implementing preventive efforts, such as working to:

  • increase vaccination
  • improve sanitation and hygiene
  • implement better tracking of people with an infection to limit contagion

Countries with less access to clean water and washing facilities typically have a higher number of typhoid cases.

Sometimes, a doctor may treat a person preemptively with antibiotics if they know the person will be in an area where the condition is endemic. Typically, they will prescribe ceftriaxone (Rocephin) or cefixime (Suprax) along with azithromycin.

Other preventive measures are as follows:

Vaccination

Before traveling to a high risk area, a person should receive a vaccine against typhoid fever.

The typhoid vaccine is available as an oral medication or a one-off injection:

  • Capsule: For adults and children over the age of 6 years, this is a live, attenuated vaccine. It consists of four tablets that a person should take every other day, the last of which at least 1 week before travel. However, the capsule version is currently not available in the U.S.
  • Shot: For adults and children over the age of 2 years, this is an inactivated vaccine a person needs to get 2 weeks before travel. A person who has previously received the vaccine should get a booster shot 2 weeks before traveling.

The typhoid vaccine is only 50–80% effective, so a person should still exercise caution when eating, drinking, and coming into contact with people.

Anyone living with HIV should not take the live, oral dose. The vaccine may also have adverse effects. After the oral vaccine, there may be:

  • GI issues
  • nausea
  • headache

Some people may faint after the vaccine.

However, severe side effects are rare with either vaccine.

Avoiding infection

Even when the symptoms of typhoid have passed, it is still possible to be carrying the bacteria.

This makes it hard to stamp out the disease, because carriers whose symptoms have finished may be less careful when washing food or interacting with others.

The following are some general rules to follow in locations where typhoid is common to help minimize the likelihood of typhoid infection:

  • Drink bottled water, preferably carbonated.
  • If there is no access to bottled water, boil available water for at least 1 minute before consumption.
  • Be wary of eating anything that someone else has handled.
  • Avoid eating at street food stands, and only eat food that is still hot.
  • Do not have ice in drinks.
  • Avoid raw fruit and vegetables, peel fruit yourself, and do not eat the peel.

A person with severe typhoid fever may experience severe vomiting, diarrhea, and abdominal bloating. This requires immediate hospitalization.

A person can also experience the following complications:

Below, we answer some commonly asked questions about typhoid.

What are the stages of typhoid fever?

The first 12–48 hours after infection are typically the asymptomatic phase. At this point, a person will have no symptoms, although the infection can spread to others.

Then, the person will usually develop GI symptoms.

By the third phase, the bacteria are already circulating in the blood, and the person will develop a high fever and other flu-like symptoms. However, each person’s infection course may be a bit different.

How long can a typhoid infection spread?

As long as a person still has typhoid bacteria in their feces, the infection can spread to others. Some people can carry the bacteria for months, and in some cases, indefinitely.

About 4% of people with a typhoid infection become chronic carriers.

What is the difference between typhoid and typhus?

Although they sound the same, typhoid and typhus are not the same conditions, as they are caused by different bacteria.

Also, typhus refers to a group of conditions that spread to people from insects, such as fleas.

Typhoid is a condition caused by the bacterium S. typhi. The main symptoms are a high fever, diarrhea, and vomiting. In some cases, there can be serious complications.

Without treatment, as many as 30% of typhoid cases are fatal. With antibiotic treatment and without complications, this rate is 1–4%.

A person living in or traveling to an area where typhoid is common should exercise caution around potentially contaminated food and water, as well as frequently wash or sanitize their hands.

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