Tag Archives: Salmonella


Salmonella infection (salmonellosis) is a common bacterial infection of the intestinal tract. Salmonella typically live in the intestines of animals and humans and are shed through feces, where the bacteria remain highly contagious. Humans become infected most frequently through contaminated food sources, such as poultry, meat and eggs. Typically, people with salmonella infection develop diarrhea, fever and abdominal cramps within 12 to 72 hours. Signs and symptoms of salmonella infection generally last four to seven days. Most healthy people recover without specific treatment. In some cases, diarrhea can be extremely dehydrating and require prompt medical attention. Life-threatening complications may also develop should the infection spread beyond your intestines. our risk of salmonella infection is higher if you travel to countries with poor sanitation. Preventive measures include proper cooking, good hygiene such as hand washing, and avoiding raw or undercooked eggs and meat.
Continue reading Salmonella

About Typhoid fever

Typhoid fever is caused by Salmonella typhi bacteria. Typhoid fever is rare in industrialized countries. However, it remains a serious health threat in the developing world. Typhoid fever spreads through contaminated food and water or through close contact with someone who’s infected. Signs and symptoms usually include high fever, headache, abdominal pain, and either constipation or diarrhea.

When treated with antibiotics, most people with typhoid fever feel better within a few days, although a small percentage may die of complications.

Vaccines against typhoid fever are available, but they’re only partially effective. Vaccines are usually reserved for those who may be exposed to the disease or are traveling to areas where typhoid fever is common.


Although children with typhoid fever sometimes become sick suddenly, signs and symptoms are more likely to develop gradually — often appearing one to three weeks after exposure to the disease. In some cases you may not become sick for as long as two months after exposure.

First stage
Once signs and symptoms do appear, you’re likely to experience:

  • Fever, often as high as 103 or 104 F (39 or 40 C)
  • Headache
  • Weakness and fatigue
  • A sore throat
  • Abdominal pain
  • Diarrhea or constipation
  • Rash

Children are more likely to have diarrhea, whereas adults may become severely constipated. During the second week, you may develop a rash of small, flat, rose-colored spots on your lower chest or upper abdomen. The rash is temporary, usually disappearing in two to five days.

Second stage
If you don’t receive treatment for typhoid fever, you may enter a second stage during which you become very ill and experience:

  • Continuing high fever
  • Either diarrhea that has the color and consistency of pea soup or severe constipation
  • Considerable weight loss
  • Extremely distended abdomen

The typhoid state
By the third week, 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.

Improvement may come slowly during the fourth week. Your fever is likely to decrease gradually until your temperature returns to normal in another week to 10 days. But signs and symptoms can return up to two weeks after your fever has subsided.

See a doctor immediately if you suspect you have typhoid fever. If you become ill while traveling in a foreign country, call the U.S. Consulate for a list of doctors. Better yet, 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. Your doctor, local or state medical society, the International Association for Medical Assistance to Travellers or the Department of State’s Office of Overseas Citizens Services can help provide the information you need.

If you develop signs and symptoms after you return home, consider consulting a doctor who focuses on international travel medicine or infectious diseases. A specialist may be able to recognize and treat your illness more quickly than can a doctor who isn’t trained in these areas.


Typhoid fever is caused by a virulent bacterium called Salmonella typhi. Although they’re related, this isn’t the same as the bacteria responsible for salmonellosis, another serious intestinal infection.

Fecal-oral route
The bacteria that cause typhoid fever spread through contaminated food or water and occasionally through direct contact with someone who is infected. In developing nations, where typhoid is endemic, most cases result from contaminated drinking water and poor sanitation. The majority of people in industrialized countries pick up the typhoid bacteria while traveling and spread it to others through the fecal-oral route.

This means that S. typhi is passed in the feces and sometimes in the urine of infected people. You can contract the infection if you eat food handled by someone with typhoid fever who hasn’t washed carefully after using the bathroom. You can also become infected by drinking water contaminated with the bacteria.

Typhoid carriers
Even after treatment with antibiotics, a small number of people who recover from typhoid fever continue to harbor the bacteria in their intestinal tract or gallbladder, often for years. These people, called chronic carriers, shed the bacteria in their feces and are capable of infecting others, although they no longer have signs or symptoms of the disease themselves.

Typhoid fever remains a serious threat in the developing world, where it affects more than 12 million people annually. The disease is endemic in India, Southeast Asia, Africa, South America and in 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 endemic
  • Have close contact with someone who is infected or has recently been infected with typhoid fever
  • Have an immune system weakened by medications such as corticosteroids or diseases such as HIV/AIDS
  • Drink water contaminated by sewage that contains S. typhi


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

Blood or 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. In 48 to 72 hours, the culture is checked under a microscope for the presence of typhoid bacteria. A bone marrow culture often is the most sensitive test for S. typhi.

Antibody and antigen testing
Your doctor may recommend other tests to help diagnose typhoid fever, such as:

  • Enzyme-linked immunosorbent assay (ELISA). This blood test looks for an antigen that’s specific to typhoid bacteria. An antigen is any substance, such as a virus, bacterium, toxin or foreign protein, that triggers an immune system response in your body. An ELISA test can identify if you carry the disease, but not whether you have an active infection.
  • Fluorescent antibody test. This test checks for antibodies to S. typhi. Antibodies are proteins produced by your immune system in response to harmful substances (antigens). Each antibody is unique and defends your body against a single antigen.


Antibiotic therapy is the only effective treatment for typhoid fever.

Commonly prescribed antibiotics
In the United States, most doctors prescribe ciprofloxacin for nonpregnant adults. Women who are pregnant and children most often receive ceftriaxone (Rocephin) injections, because ciprofloxacin has been associated with problems in these groups. All of these drugs can cause side effects, and long-term use can lead to the development of antibiotic-resistant strains of bacteria.

Problems with antibiotic resistance
In the past, the drug of choice was chloramphenicol. Doctors no longer commonly use it, however, because of severe side effects, a high relapse rate and widespread bacterial resistance. In fact, the existence of antibiotic-resistant bacteria is a growing problem in the treatment of typhoid, especially in the developing world. In recent years, S. typhi also has proved resistant to trimethoprim-sulfamethoxazole and ampicillin.

Supportive therapy
Other treatment steps aimed at managing symptoms 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 in your arm (intravenously).
  • Eating a healthy diet. Nonbulky, high-calorie meals can help replace the nutrients you lose when you’re sick.


In many developing nations, the public health goals that can help prevent and control typhoid — safe drinking water, improved sanitation and adequate medical care — may be difficult to achieve. For that reason, some experts believe that vaccinating high-risk populations is the best way to control typhoid fever.

Two vaccines are currently in use — one is injected in a single dose, and the other is given orally over a period of days. Neither is 100 percent effective, and both require repeat vaccinations.

If you’re traveling to an area where typhoid fever is endemic, consider being vaccinated. But because the vaccine won’t provide complete protection, be sure to follow these guidelines as well:

  • Wash your hands. Frequent hand washing is the best way to control infection. Wash your hands thoroughly with hot, soapy water, especially 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 is endemic. For that reason, drink only bottled water or canned or bottled carbonated beverages, wine and beer. Carbonated bottled water is safer than uncarbonated bottled water is. Wipe the outside of all bottles and cans before you open them. 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 unsafe 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 contaminated.

To prevent infecting others
If you’re recovering from typhoid, these measures can help keep others safe:

  • Wash your hands often. This is the single most important thing you can do to keep from spreading the infection to others. Use plenty of hot, soapy water and scrub thoroughly for at least 30 seconds, especially before eating and after using the toilet.
  • Clean household items daily. Clean toilets, door handles, telephone receivers and water taps at least once a day with a household cleaner and paper towels or disposable cloths.
  • 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.
  • Keep personal items separate. Set aside towels, bed linen and utensils for your own use and wash them frequently in hot, soapy water. Heavily soiled items can be soaked first in disinfectant.