Typhoid Fever

(This information is not intended to be a substitute for the advice of a doctor or a recommendation for any particular treatment plan. Like any printed material, it may become out of date over time. It is important that you rely on the advice of a doctor for your specific condition.)

Typhoid fever is a life-threatening illness caused by the bacterium Salmonella Typhi. This bacteria lives only in humans. Persons with typhoid fever carry the bacteria in their bloodstream and intestinal tract. In addition, a small number of persons, called carriers , recover from typhoid fever but continue to carry the bacteria. Both ill persons and carriers shed S. Typhi in their feces (stool). You can get typhoid fever if you eat food or drink beverages that have been handled by a person who is shedding S. Typhi or if sewage contaminated with S. Typhi bacteria gets into the water you use for drinking or washing food. Therefore, typhoid fever is more common in areas of the world where handwashing is less frequent and water is likely to be contaminated with sewage. Once S. Typhi bacteria are eaten or drunk, they multiply and spread into the bloodstream. The body reacts with fever and other signs and symptoms.

Two basic actions can protect you from typhoid fever:
1. Avoid risky foods and drinks.
2. Get vaccinated against typhoid fever.

"Boil it, cook it, peel it, or forget it"
• If you drink water, buy it bottled or bring it to a rolling boil for 1 minute before you drink it. Bottled carbonated water is safer than uncarbonated water.
• Ask for drinks without ice unless the ice is made from bottled or boiled water. Avoid popsicles and flavored ices that may have been made with contaminated water.
• Eat foods that have been thoroughly cooked and that are still hot and steaming.
• Avoid raw vegetables and fruits that cannot be peeled. Vegetables like lettuce are easily contaminated and are very hard to wash well.
• When you eat raw fruit or vegetables that can be peeled, peel them yourself. (Wash your hands with soap first.) Do not eat the peelings.
• Avoid foods and beverages from street vendors. It is difficult for food to be kept clean on the street, and many travelers get sick from food bought from street vendors.

Remember that you will need to complete your vaccination at least 1 week before you travel so that the vaccine has time to take effect. Typhoid vaccines lose effectiveness after several years; if you were vaccinated in the past, check with your doctor to see if it is time for a booster vaccination. Taking antibiotics will not prevent typhoid fever; they only help treat it.

There are two types of typhoid vaccines:
• Injectable Vi CPS. Capsular Vi polysaccharide vaccine (Vi CPS), containing 25 μg of polysaccharide per dose (0.5 ml), is given I.M. in a single dose and produces protection 7 days after injection. In endemic areas, the protective efficacy is 72% after 1.5 years and 50% after 3 years. Booster is needed every 2 years.
• Oral Ty21a is live-attenuated mutant strain of Salmonella typhi Ty21a, supplied as enteric coated capsules, given orally in three doses (four in North America) 2 days apart (on alternate days), and produces protection 7 days after the final dose. Seven years after the final dose the protective efficacy is 67% in residents of endemic areas but may be less for travelers. Proguanil, mefloquine and antibiotics should be stopped from 3 days before until 3 days after giving Ty21a. Booster is needed every 5 years.

Persons with typhoid fever usually have a sustained fever as high as 39° to 40° C. They may also feel weak, or have stomach pains, headache, or loss of appetite. In some cases, patients have a rash of flat, rose-colored spots. The only way to know for sure if an illness is typhoid fever is to have samples of stool or blood tested for the presence of S. Typhi.

If you suspect you have typhoid fever, see a doctor immediately. You will probably be given an antibiotic to treat the disease. Three commonly prescribed antibiotics are ampicillin, trimethoprim-sulfamethoxazole, and ciprofloxacin. Persons given antibiotics usually begin to feel better within 2 to 3 days, and deaths rarely occur. However, persons who do not get treatment may continue to have fever for weeks or months, and as many as 20% may die from complications of the infection.

Even if your symptoms seem to go away, you may still be carrying S. Typhi. If so, the illness could return, or you could pass the disease to other people. In fact, if you work at a job where you handle food or care for small children, you may be barred legally from going back to work until a doctor has determined that you no longer carry any typhoid bacteria. If you are being treated for typhoid fever, it is important to do the following: Keep taking the prescribed antibiotics for as long as the doctor has asked you to take them. Wash your hands carefully with soap and water after using the bathroom, and do not prepare or serve food for other people. This will lower the chance that you will pass the infection on to someone else.

(Source: U.S. Centers for Disease Control and Prevention)

Typhoid Mary: A Famous Case of Salmonella’s Spread

The story of Typhoid Mary starts in the summer of 1906 on the North Shore of Long Island, New York.

Mary came to the United States from Ireland in 1883 and earned a living by working as a cook. On August 4, 1906, Mary began working for the Charles Warren family, a wealthy New York banker. His family of four had rented a summer house in the town of Oyster Bay, and brought seven servants with them. At the beginning of the summer, from August 27 to September 3 of that year, six of the 11 people living in the house became infected with typhoid fever. The local public health department investigated the house to try to determine the source of the outbreak, but could not find the cause. The situation worried the owner of the house, so he hired George Soper, a sanitation engineer, to try to figure out what was causing the illness.

Soper was able to narrow down the cause of the outbreak to the servants. He had a hunch that the source was the cook, Mary Mallon. Mary had arrived in the household exactly three weeks before the typhoid outbreak, and three weeks is the incubation period (the amount of time between a person’s exposure to a disease-causing agent and the first appearance of symptoms) for typhoid fever. Soper surmised that Mary was transmitting the bacteria, which were shed in her feces, to the foods she prepared and served to her employers. At the hospital, tests determined that Mary was indeed carrying Salmonella typhi.

Mary knew that she would not be able to work as a cook in private homes, so she took jobs instead in several hotels and institutions. Just as had happened before with the families she cooked for, typhoid fever broke out in the hotels and institutions where she was employed. To avoid getting caught by the authorities, she moved quickly from job to job. Health officials finally found her in 1915. At that time, she was working at the Sloane Maternity Hospital in Manhattan, New York, where a large typhoid outbreak occurred. At least 25 hospital employees came down with the illness, and 2 of them died. Mary was identified and captured.

(Source: Donald Emmeluth - Typhoid fever, 2004)