Typhoid Fever
Typhoid Fever
Definition
Typhoid fever is a severe infection caused by a bacterium, Salmonella typhi. S. typhi is in the same family of bacteria as the type spread by chicken and eggs, commonly known as salmonella poisoning or food poisoning. S. typhi bacteria do not have vomiting and diarrhea as the most prominent symptoms of their presence in humans. Instead, persistently high fever is the hallmark of S. typhi infection.
Description
S. typhi bacteria are passed into the stool and urine of infected patients. They may continue to be present in the stool of asymptomatic carriers, who are persons who have recovered from the symptoms of the disease but continue to carry the bacteria. This carrier state occurs in about 3% of all individuals recovered from typhoid fever.
Typhoid fever is passed from person to person through poor hygiene, such as incomplete or no hand washing after using the toilet. Persons who are carriers of the disease and who handle food can be the source of epidemic spread of typhoid. One such individual gave her name to the expression "Typhoid Mary," a name given to someone whom others avoid.
Typhoid fever is a particularly difficult problem in parts of the world with poor sanitation practices. There are about 16 million cases of typhoid reported around the world each year. In the United States, most patients who contract typhoid fever have recently returned from travel to another country where typhoid is much more common, including Mexico, Peru, Chile, India, and Pakistan. However, there have been reports in the early 2000s of typhoid outbreaks within the United States that were unrelated to recent travel. One such outbreak occurred in Queens, New York, and was traced to a worker in a local restaurant.
Causes and symptoms
S. typhi must be ingested to cause disease. Transmission often occurs when a person in the carrier state does not wash hands thoroughly (or not at all) after defecation and serves food to others. This pathway is sometimes called the fecal-oral route of disease transmission. In countries where open sewage is accessible to flies, the insects land on the sewage, pick up the bacteria, and then contaminate food to be eaten by humans.
After being swallowed, the S. typhi bacteria head down the digestive tract, where they are taken in by cells called mononuclear phagocytes. These phagocytes are cells of the immune system, whose job it is to engulf and kill invading bacteria and viruses. In the case of S. typhi, however, the bacteria are able to survive ingestion by the phagocytes, and multiply within these cells. This period of time, during which the bacteria are multiplying within the phagocytes, is the 10 to 14-day incubation period of typhoid fever. When huge numbers of bacteria fill an individual phagocyte, they spill out of the cell and into the bloodstream, where their presence begins to cause symptoms.
The presence of increasingly large numbers of bacteria in the bloodstream (bacteremia ) is responsible for an increasingly high fever, which lasts throughout the four to eight weeks of the disease in untreated individuals. Other symptoms of typhoid fever include constipation (at first), extreme fatigue, headache, joint pain, and a rash across the abdomen known as rose spots.
The bacteria move from the bloodstream into certain tissues of the body, including the gallbladder and lymph tissue of the intestine (called Peyer's patches). The tissue's response to this invasion causes symptoms ranging from inflammation of the gallbladder (cholecystitis ) to intestinal bleeding to actual perforation of the intestine. Perforation of the intestine refers to an actual hole occurring in the wall of the intestine, with leakage of intestinal contents into the abdominal cavity. This leakage causes severe irritation and inflammation of the lining of the abdominal cavity, which is called peritonitis. Peritonitis is a frequent cause of death from typhoid fever.
MARY MALLON (1869–1938)
Mary Mallon was born in Cookstown, Ireland, on September 23, 1869, to Catherine Igo and John Mallon. As a teenager, Mallon left her parents and immigrated to New York to live with an aunt and uncle. Until 1906, when George A. Soper began to study an outbreak of typhoid fever in Long Island, little was known about Mallon.
Soper was called to identify possible causes of an eruption of typhoid fever at a summer house in Oyster Bay. After examining the food and water in a futile attempt to discover contaminants, Soper decided that the disease was probably transmitted by a human carrier. He soon learned that the cook had disappeared and tracked Mallon to her new place of employment, expecting her cooperation in dealing with the matter. Soper eventually turned the case over to the New York City Department of Health. When Mallon was ultimately caught, she refused treatment and was held for three years as a threat to the public. In 1910, a judge granted her release with the stipulation that she not seek employment as a cook, since the disease was transmitted through food. Mallon agreed but, in 1915, an outbreak of typhoid at a hospital was, once again, linked to her. When Soper investigated this incident he learned that employees had nicknamed one of the cooks "Typhoid Mary."
After Mallon was found, she was taken into custody, and spent the rest of her life at Riverside Hospital. Mallon died on November 11, 1938.
Other complications of typhoid fever include liver and spleen enlargement, sometimes so great that the spleen ruptures or bursts; anemia, or low red blood cell count due to blood loss from the intestinal bleeding; joint infections, which are especially common in patients with sickle cell anemia and immune system disorders; pneumonia caused by a bacterial infection—usually Streptococcus pneumoniae —which is able to take hold due to the patient's weakened state; heart infections; and meningitis and infections of the brain, which cause mental confusion and even coma. It may take a patient several months to recover fully from untreated typhoid fever.
Diagnosis
In some cases, the doctor may suspect the diagnosis if the patient has already developed the characteristic rose spots, or if he or she has a history of recent travel in areas with poor sanitation. The diagnosis, however, is confirmed by a blood culture. Samples of a patient's stool, urine, and bone marrow can also be used to grow S. typhi in a laboratory for identification under a microscope. Cultures are the most accurate method of diagnosis. Blood cultures usually become positive in the first week of illness in 80% of patients who have not taken antibiotics.
Treatment
Antibiotics are the treatment of choice for typhoid fever. As of the early 2000s, the most frequently used drugs are ceftriaxone and cefoperazone. Ciprofloxacin is sometimes given as follow-up therapy.
Carriers of S. typhi must be treated even when they do not show any symptoms of the infection, because carriers are responsible for the majority of new cases of typhoid fever. Eliminating the carrier state is actually a fairly difficult task. It requires treatment with one or even two different medications over a period of four to six weeks. The antibiotics most commonly given are ampicillin (sometimes given together with probenecid) and amoxicillin. In the case of a carrier with gallstones, surgery may need to be performed to remove the gallbladder. This measure is necessary because typhoid bacteria are often housed in the gallbladder, where they may survive in spite of antibiotic treatment. In some patients, however, treatment with rifampin and trimethoprim-sulfamethoxazole is sufficient to eradicate the bacteria from the gallbladder without surgery.
Prognosis
The prognosis for recovery is good for most patients. In the era before effective antibiotics were discovered, about 12% of all typhoid fever patients died of the infection. Now, however, fewer than 1% of patients who receive prompt antibiotic treatment will die. The mortality rate is highest in the very young and very old, and in patients suffering from malnutrition. The most ominous signs are changes in a patient's state of consciousness, including stupor or coma.
Prevention
Hygienic sewage disposal systems in a community as well as proper personal hygiene are the most important factors in preventing typhoid fever. Immunizations are available for travelers who expect to visit countries where S. typhi is a known public health problem. Some of these immunizations provide only short-term protection (for a few months), while others may be effective for several years. Efforts are being made to develop vaccines that provide a longer period of protection with fewer side effects from the vaccine itself. The most commonly reported side effects are flu-like muscle cramps and abdominal pain. As of earlt 2004, these vaccines are also being studied as possible antibioterrorism agents.
KEY TERMS
Asymptomatic— A state in which a person experiences no symptoms of a disease.
Bacteremia— Bacteria in the blood.
Carrier— A person who has a particular disease agent present within his/her body, and can pass this agent on to others, but who displays no symptoms of infection.
Epidemic— A large number of cases of the same disease or infection all occurring within a short time period in a specific location.
Mononuclear phagocyte— A type of cell of the human immune system that ingests bacteria, viruses, and other foreign matter, thus removing potentially harmful substances from the bloodstream. These substances are usually then digested within the phagocyte.
Rose spots— A pinkish rash across the trunk or abdomen that is a classic sign of typhoid fever.
Resources
BOOKS
Beers, Mark H., MD, and Robert Berkow, MD., editors. "Enterobacteriaceae Infections." In The Merck Manual of Diagnosis and Therapy. Whitehouse Station, NJ: Merck Research Laboratories, 2004.
PERIODICALS
Begier,E.M., D. R. Burwen, P. Haber, et al. "Postmarketing Safety Surveillance for Typhoid Fever Vaccines from the Vaccine Adverse Event Reporting System, July 1990 through June 2002." Clinical Infectious Diseases 38 (March 15, 2004): 771-779.
Parry, C. M. "Typhoid Fever." Current Infectious Diseases Report 6 (February 2004): 27-33.
Yoon, J., S. Segal-Maurer, and J. J. Rahal. "An Outbreak of Domestically Acquired Typhoid Fever in Queens, NY." Archives of Internal Medicine 164 (March 8, 2004): 565-567.
ORGANIZATIONS
Centers for Disease Control and Prevention. 1600 Clifton Rd., NE, Atlanta, GA 30333. (800) 311-3435, (404) 639-3311. 〈http://www.cdc.gov〉.
Typhoid Fever
Typhoid Fever
Disease History, Characteristics, and Transmission
Introduction
Typhoid fever, sometimes also known as enteric fever, is a potentially life-threatening infection caused by the bacterium Salmonella typhi. It is rare in the United States and other Western countries, and most cases in these areas have been acquired when traveling abroad. The disease is spread by contaminated food and water.
People who have had typhoid fever may be infectious for many months after they have recovered. One of the most famous carriers of typhoid fever was Mary Mallon, a cook for a family in New York City between 1901 and 1915. She infected 53 people with typhoid, and three of those she infected died. Typhoid is treatable with antibiotics, but can have a fatality rate of up to 30% if it goes untreated. There is also a vaccine that travelers can use to protect themselves in areas where typhoid is endemic. However, protection afforded by the vaccine is not lifelong and those who may be exposed may need to have a booster dose.
Disease History, Characteristics, and Transmission
Typhoid fever is caused by the bacterium Salmonella typhi, which infects the blood and the intestines. Paratyphoid fever is a milder condition caused by related species of Salmonella. The two are sometimes referred to as enteric fever, because of the site of infection. Salmonella species also cause food poisoning and only infect humans—there is no animal reservoir. At one time, typhoid was confused with typhus, because of the similarity between the symptoms. However, it is now known that the causes and pathology of the two diseases are very different.
The symptoms of typhoid include high fever, chills, cough, muscle pain, weakness, stomach pain, headache, and a rash made up of flat, rose-colored spots. Diarrhea is a less common symptom of typhoid fever, even though it is a gastrointestinal disease. Sometimes there are mental changes, known as “typhoid psychosis.” A characteristic feature of typhoid psychosis is plucking at the bedclothes, if the patient is confined to bed.
Typhoid fever is diagnosed by identification of S. typhi in blood or in stool samples. Left untreated, fever may persist for many months, leading to potentially fatal complications. For instance, the mucosal walls of the intestine may weaken, allowing the infection to spread into the bowel. Typhoid fever has a 1% fatality rate in the United States, assuming prompt treatment with antibiotics. Without treatment, the death rate rises to about 10%. In parts of Africa and Asia, where the disease is far more common, mortality rates from typhoid may approach 30%.
WORDS TO KNOW
ENDEMIC: Present in a particular area or among a particular group of people.
MULTI-DRUG RESISTANCE: Multi-drug resistance is a phenomenon that occurs when an infective agent loses its sensitivity against two or more of the drugs that are used against it.
TYPHUS: A disease caused by various species of Rickettsia, characterized by a fever, rash, and delirium. Insects such as lice and chiggers transmit typhus. Two forms of typhus, epidemic disease and scrub typhus, are fatal if untreated.
Typhoid fever is spread through food and water contaminated by people with typhoid shedding S. typhi. About 1–4% of typhoid cases become chronic carriers— that is, they continue to shed S. typhi in their urine and feces for more than a year after recovery. Typhoid is also transmitted by water into which contaminated sewage has been discharged.
Scope and Distribution
Typhoid has long been a feared human disease. According to the World Health Organization (WHO), there are around 17 million cases of typhoid fever each year, of which 600,000 prove fatal. This is considered to be a conservative estimate of the scale of the problem. Typhoid fever is endemic in the Indian subcontinent and in parts of Asia, Africa, and Central and South America. In some of these places, typhoid is one of the top five causes of death. The peak age for contracting typhoid in countries where it is endemic is between five and 19 years, although it can affect people of either sex at any age.
In the United States, around 400 cases of typhoid fever are reported each year, of which 70% are contracted during travel to areas where it is endemic. In England and Wales, there are 150–200 cases of typhoid annually, again mainly in returning travelers. People have been known to develop typhoid after less than one week's stay in an endemic country. The disease has been all but eliminated from developed nations, although sporadic cases such as those mentioned above still arise.
Treatment and Prevention
Typhoid fever is treated with antibiotics, with ampicillin, trimethoprim-sulfamethoxazole, and ciprofloxacin being the preferred choices. However, a major concern is the emergence of multi-drug resistant strains of S. typhi in parts of Asia and South America. Therefore, the choice of antibiotic should be guided by local knowledge of which drugs will be effective against the strain of S. typhi involved in the infection.
There are two vaccines against typhoid—oral and injectable—and they are about 75% effective. Travelers should consult their national public health authority as to whether they need to be vaccinated against typhoid, if they are going to a country where the disease is endemic. Even if they have been previously vaccinated, a booster dose may be necessary.
Taking care to avoid risky food or drink is as important as being vaccinated in protecting against typhoid fever. All drinking water should either be bottled or boiled rapidly for one minute. Ice should be avoided, since it could have been made from contaminated water. Travelers in countries where there is typhoid should only eat food that is thoroughly cooked and is still hot and steaming. Raw vegetables and fruits should be avoided—unless they can be peeled, in which case hands should be carefully washed first. Many travelers get sick with typhoid—and other gastrointestinal illnesses—by eating food they bought from street vendors. It is impossible to observe a high standard of cooking hygiene under street conditions.
People who have had typhoid fever ought to assume they have carrier status, unless a series of stool samples analyses for S. typhi proves negative for the bacterium. Therefore, they should not prepare or serve food, and should take extra care with personal hygiene.
Impacts and Issues
Typhoid continues to be a problem worldwide because of poor sanitation, which forces people into frequent contact with contaminated water and food. Inadequate sewage disposal continues to be an issue in too many places, placing the populations at risk of many diseases, including typhoid fever.
The higher mortality rates from typhoid fever seen in many developing countries can be attributed to a weak—or non-existent—healthcare infrastructure, which does not provide ready access to the antibiotics that could cure the disease. War and natural disasters, such as earthquakes, disrupt clean water supplies, which is why typhoid has often accompanied such disasters, both today and throughout the course of history.
For example, the WHO reported a significant outbreak of typhoid fever in Kinshasa in the Democratic Republic of the Congo involving a total of 13,400 cases by mid-December 2004. The fatality rate from the outbreak was 22% (134 deaths), mainly due to peritonitis, a severe inflammation of the lining of the abdominal cavity. Very poor sanitation and lack of access to clean drinking water had been reported in the affected areas. The number of cases increased to over 42,000 through the early months of 2005, while the death toll mounted to 214. The medical charity Médicins sans Frontières Belgium helped to provide clean water which, along with other control measures including health education, began to bring the outbreak under control.
IN CONTEXT: TYPHOID MARY
Mary Mallon, a known carrier of typhoid, refused to stop behaving in ways that risked spreading the disease and forced the government to jail her to protect the public health. The first person in North America to be identified as a healthy typhoid carrier, Mallon was an Irish-born cook who worked for wealthy New Yorkers. In 1906, she was employed in the rented summer home of banker Charles Henry Warren in Oyster Bay, Long Island, when typhoid fever struck six people in the household of eleven. The owners of the rental house hired investigators to determine the source of the epidemic. The detectives traced forty-seven cases of typhoid and three deaths to Mallon.
A contagious bacterial disease, typhoid had a fatality rate of ten percent, although milder cases also occurred. Typhoid bacteria remain in the intestine, liver, and bile ducts until they are transmitted via urine and feces. Victims suffer fever, chills, headaches, malaise, severe cramping, and diarrhea or constipation. The symptoms often continue for over a month. While sick, persons with typhoid weaken and became susceptible to complications such as dehydration or intestinal bleeding.
As a single, working class woman, Mallon needed to work in order to support herself. She was reputedly an excellent cook, but was unaware of the germ theory of disease and of the simple measures (such as handwashing) necessary to prevent spreading disease. Investigators discovered that thirty percent of the bacteria excreted by Mallon in her urine were the bacteria that cause typhoid.
In March 1907, New York City health officials literally dragged Mallon kicking and screaming into a city ambulance. They deposited her in a small cottage on North Brother Island that formed part of the grounds of an isolation hospital. Although she was released for brief periods, Mallon died in captivity in 1938 at the age of sixty-nine, after spending twenty-six years in her island prison.
See AlsoTravel and Infectious Disease; War and Infectious Disease.
BIBLIOGRAPHY
Books
Wilks, David, Mark Farrington, and David Rubenstein. The Infectious Diseases Manual. 2nd ed. Malden, UK: Blackwell, 2003.
Wilson, Walter R., and Merle A. Sande. Current Diagnosis & Treatment in Infectious Diseases. New York: McGraw Hill, 2001.
Web Sites
Centers for Disease Control and Prevention. “Typhoid Fever.” January 10, 2005. <http://www.cdc.gov/ncidod/dbmd/diseaseinfo/typhoidfever_g.htm> (accessed May 2, 2007).
World Health Organization. Initiative for Vaccine Research. “Typhoid.” <http://www.who.int/vaccine_research/diseases/typhoid/en/index.html> (accessed May 2, 2007).
Susan Aldridge
Typhoid Fever
Typhoid Fever
How Salmonella typhi is spread
Progression and symptomatology
Typhoid fever is a severe infection causing a sustained high fever. It is caused by the bacteria Salmonella typhi, which is in the same genus of bacteria as the type spread by chicken and eggs, commonly known as Salmonella poisoning, or food poisoning. S. typhi bacteria, however, do not multiply directly in food, as do the Salmonella responsible for food poisoning, nor does it have vomiting and diarrhea as the most prominent symptoms. Instead, persistently high fever is the hallmark of infection with Salmonella typhi.
How Salmonella typhi is spread
S. typhi bacteria are passed into the stool and urine of infected patients, and may continue to be present in the stool of asymptomatic carriers (individuals who have recovered from the symptoms of the disease, but continue to carry the bacteria). This carrier state occurs in about 3% of those individuals recovered from typhoid fever.
The disease is passed between humans, then, through poor hygiene, such as deficient hand washing after toileting. Individuals who are carriers of the disease and who handle food can be the source of the epidemic spread of typhoid. One such individual is the source for the expression “Typhoid Mary,” a name given to someone with whom others wish to avoid all contact. The real “Typhoid Mary” was a cook named Mary Mallon (1855–1938) who lived in New York City around 1900. She was a carrier of typhoid and was the cause of at least 53 outbreaks of typhoid fever.
Typhoid fever is a particularly difficult problem in parts of the world with less-than-adequate sanitation practices. In the United States, many patients who become afflicted with typhoid fever have recently returned from travel to another country, where typhoid is much more prevalent, such as Mexico, Peru, Chile, India, and Pakistan.
Progression and symptomatology
To cause disease, the S. typhi bacteria must be ingested. This often occurs when a carrier does not wash hands sufficiently well after defecation, and then serves food to others. In countries where open sewage is accessible to flies, the insects land on the sewage, pick up the bacteria, and then land on food that is to be eaten by humans.
Ingested bacteria head down the gastrointestinal tract, where they are taken in by cells called mononu-clear phagocytes. These phagocytes usually serve to engulf and kill invading bacteria and viruses. However, in the case of S. typhi, the bacteria survive ingestion by the phagocytes, and multiply within these cells. This period of time, during which the bacteria are multiplying within the phagocytes, is the 10-14 day incubation period. When huge numbers of bacteria fill an individual phagocyte, the bacteria are discharged out of the cell and into the bloodstream, where their presence begins to cause symptoms.
The presence of increasingly large numbers of bacteria in the bloodstream (called bacteremia) are responsible for an increasingly high fever, which lasts throughout the four to eight weeks of the disease, in untreated individuals. Other symptoms include constipation (initially), extreme fatigue, headache, a rash across the abdomen known as “rose spots,” and joint pain.
The bacteria move from the bloodstream into certain tissues of the body, including the gallbladder and lymph tissue of the intestine (called Peyer’s patches). The tissue’s inflammatory response to this invasion causes symptoms ranging from inflammation of the gallbladder (cholecystitis) to intestinal bleeding and actual perforation of the intestine. Perforation of the intestine refers to an actual hole occurring in the wall of the intestine, with leakage of intestinal contents into the abdominal cavity. This causes severe irritation and inflammation of the lining of the abdominal cavity, called peritonitis, which is frequently a fatal outcome of typhoid fever.
Other complications of typhoid fever include liver and spleen enlargement (sometimes so extreme that the spleen ruptures); anemia (low red blood cell count due to blood loss from the intestinal bleeding); joint infections (especially frequent in patients with sickle cell anemia and immune system disorders); pneumonia (due to a superimposed infection, usually by Streptococcus pneumoniae ); heart infections; meningitis; and infections of the brain (causing confusion and even coma). Untreated typhoid fever may take several months to resolve fully.
Diagnosis
samples of a patient’s stool, urine, blood, and bone marrow can all be used to culture (grow) the S. typhi bacteria in a laboratory for identification under a microscope. These types of cultures are the most accurate methods of diagnosis.
Treatment
chloramphenicol is the most effective drug treatment for S. typhi, and symptoms begin to improve slightly after only 24-48 hours of receiving the medication. Another drug, ceftriaxone, has been used recently, and is also extremely effective, lowering fever fairly quickly.
Carriers of S. typhi must be treated even when asymptomatic, as they are responsible for the majority
KEY TERMS
Asymptomatic —A state in which an individual experiences no symptoms of a disease.
Bacteremia —Bacteria in the blood.
Carrier —An individual who has a particular bacteria present within his/her body, and can pass this bacteria on to others, but who displays no symptoms of infection.
Epidemic —A situation in which a particular infection is experienced by a very large percentage of the people in a given community within a given time frame.
Mononuclear phagocytes —A type of cell of the human immune system which is responsible for ingesting bacteria, viruses, and other foreign matter, thus removing potentially harmful substances from the bloodstream.
of new cases of typhoid fever. Eliminating the carrier state is actually a fairly difficult task, and requires treatment with one or even two different medications for four to six weeks. In the case of a carrier with gall stones, surgery may be needed to remove the gall bladder because the S. typhi bacteria are often housed in the gall bladder, where they may survive despite antibiotic treatment.
Prevention
hygienic sewage disposal systems in a community, as well as hygienic personal practices, are the most important factors in preventing typhoid fever. For travelers who expect to go to countries where S. typhi is a known public health problem, two different immunizations are available. Both provide protection in 50-80% of recipients, and both require booster immunizations after 2-5 years.
Resources
BOOKS
Cormican, M. G., and M. A. Pfaller. “Molecular Pathology of Infectious Diseases.” In Clinical Diagnosis and Management by Laboratory Methods. 20th ed. Philadelphia: W. B. Saunders, 2001.
Isselbacher, Kurt J., et al. Harrison”s Principles of Internal
Medicine, 16th ed. New York: McGraw Hill, 2004.
Kobayashi, G., Patrick R. Murray, Ken Rosenthal, and Michael Pfaller. Medical Microbiology. St. Louis, MO: Mosby, 2003.
OTHER
“Typhoid Fever.” Centers for Disease Control and
Prevention. < http://www2.ncid.cdc.gov/travel/yb/utils/ybGet.asp?section=dis&obj=typhoid.htm > (accessed November 27, 2006).
Rosalyn Carson-DeWitt
Typhoid Fever
Typhoid Fever
What Happens When People Have Typhoid Fever?
How Is Typhoid Fever Prevented?
Typhoid fever is a bacterial infection that is common in many parts of the world. It is spread by contaminated water and food and primarily affects the digestive system.
KEYWORDS
for searching the Internet and other reference sources
Foodborne diseases
Salmonella typhi
Waterborne diseases
What Is Typhoid?
In many developing countries, typhoid fever is a major problem. It is estimated to cause 16 million illnesses and more than half a million deaths each year worldwide. It is especially common in parts of Asia, Africa, and South America where pure water is not readily available and sewage treatment is limited. In many countries, children are the most likely to get typhoid.
The U.S. and the World
About 16 million cases of typhoid fever occur each year worldwide, and more than 600,000 people die from it.
The disease is common in many underdeveloped nations of the world, especially parts of Asia and in South America with unsanitary water and food preparation. The situation is made more difficult because the disease is showing resistance to some of the traditional antibiotics used to treat those who are infected.
About 400 cases a year are reported in the United States, but about 70 percent of them involve people who had traveled overseas.
In 1998-1999,13 people in Florida contracted typhoid fever when they drank shakes made with a frozen tropical fruit containing Salmonelli typhi.
Typhoid fever is suspected in the deaths of such famous people as Alexander the Great, Wilbur Wright of the Wright Brothers, and poet Gerard Manley Hopkins.
Typhoid used to be a serious problem in the United States as well. Early in the twentieth century, before clean water supplies and sewage systems to dispose of human waste were widely available, it caused about 35,000 illnesses each year. Technological advancements in sewage and water treatment have made typhoid fever rare in industrialized countries. Only about 400 cases are reported each year in the United States. Most of them are acquired while traveling abroad.
What Causes Typhoid Fever?
Typhoid fever is caused by a bacterium called Salmonella typhi. It is related to the salmonella bacteria that cause food poisoning, but they are not exactly the same.
Salmonella typhi bacteria are present in the solid wastes (stool) of infected people, including some “healthy carriers” who have no symptoms of illness. The bacteria can spread if human waste gets into water that is used for drinking, irrigating crops, or washing food. Typhoid also occasionally is transmitted through an infected person who is working in food preparation. Once swallowed, the bacteria move from the digestive tract into the bloodstream and then to the liver, spleen, gall bladder, and lymph nodes.
Typhoid Mary
Some people, called carriers, can be infected with Salmonella typhi but not develop typhoid fever. If they prepare food for others, however, they may contaminate the food they handle and pass the bacteria on to other people who eat it and then may get sick.
The most famous typhoid carrier was Mary Mallon, also known as Typhoid Mary, who worked as a cook in homes in New York and New Jersey in the early 1900s. Fifty-one cases of typhoid fever resulting in three deaths were traced to her. Mallon never was sick herself, however, and she never accepted that she had infected anyone else.
Against her will, the authorities confined Mallon to a hospital on North Brother Island in New York’s East River. Three years later, in 1910, they released her on condition that she never work as a cook again. But in 1915, typhoid struck a maternity hospital in Manhattan, and it turned out that Mallon had cooked there. She spent the rest of her life, 23 years, as a captive on North Brother Island.
What Happens When People Have Typhoid Fever?
Symptoms
The symptoms of typhoid fever come on gradually. At first, people may get a headache, stomachache, and constipation*. They develop a fever and lose their appetite. In some cases, they may get rose spots, a rash mostly on the chest and abdomen. As symptoms worsen, the fever may rise as high as 103 to 104 degrees Fahrenheit. People often develop bloody diarrhea, become dehydrated (lose fluids faster than they are replaced), and start acting confused or disoriented. In severe cases, people may go into a coma, a state of deep unconsciousness, and die.
- * constipation
- is the sluggish movement of the bowels, usually resulting in infrequent hard stools.
Diagnosis and Treatment
A blood or urine test usually can detect the presence of the bacterium that causes typhoid fever. Antibiotic drugs that fight the bacterial infection can make the illness shorter and milder and prevent complications. Fluids may be given as well to counter the effects of diarrhea. Severe infections can lead to a perforation (hole) in the intestine that requires surgery to repair.
How Is Typhoid Fever Prevented?
Clean water supplies and effective waste disposal systems are the best ways of preventing typhoid, but these are lacking in many countries. A vaccine is available that is about 70 percent effective for several years.
Travelers to countries where typhoid fever is common should drink only boiled or bottled water. They should eat only food that has been properly cooked or fruit that they peel themselves and that has not been washed with tap water. The U.S. Centers for Disease Control and Prevention sums up advice for travelers this way: “Boil it, cook it, peel it, or forget it.”
See also
Bacterial Infections
Fever
Gastroenteritis
Salmonellosis
Resources
U.S. Centers for Disease Control and Prevention (CDC), 1600 Clifton Road N.E., Atlanta, GA 30333. CDC posts a fact sheet about typhoid fever at its website. http://www.cdc.gov/ncidod/dbmd/diseaseinfo/typhoidfever_g.htm
World Health Organization (WHO), Avenue Appia 20, 1211 Geneva 27, Switzerland. WHO’s website posts fact sheets about typhoid fever and other vaccine preventable diseases at its website. http://www.who.org/home/map_ht.html
Typhoid Fever
Typhoid fever
Typhoid fever is a severe infection causing a sustained high fever, and caused by the bacteria Salmonella typhi. S. typhi is in the same tribe of bacteria as the type spread by chicken and eggs, commonly known as "Salmonella poisoning," or food poisoning . S. typhi bacteria, however, do not multiply directly in food, as do the Salmonella responsible for food poisoning, nor does it have vomiting and diarrhea as the most prominent symptoms. Instead, persistently high fever is the hallmark of infection with Salmonella typhi.
How Salmonella typhi is spread
S. typhi bacteria are passed into the stool and urine of infected patients, and may continue to be present in the stool of asymptomatic carriers (individuals who have recovered from the symptoms of the disease , but continue to carry the bacteria). This carrier state occurs in about 3% of all individuals recovered from typhoid fever.
The disease is passed between humans, then, through poor hygiene, such as deficient hand washing after toileting. Individuals who are carriers of the disease and who handle food can be the source of epidemic spread of typhoid. One such individual is the source for the expression "Typhoid Mary," a name given to someone with whom others wish to avoid all contact. The real "Typhoid Mary" was a cook named Mary Mallon (1855-1938) who lived in New York City around 1900. She was a carrier of typhoid and was the cause of at least 53 outbreaks of typhoid fever.
Typhoid fever is a particularly difficult problem in parts of the world with less-than-adequate sanitation practices. In the United States, many patients who become afflicted with typhoid fever have recently returned from travel to another country, where typhoid is much more prevalent, such as Mexico, Peru, Chile, India, and Pakistan.
Progression and symptomatology
To cause disease, the S. typhi bacteria must be ingested. This often occurs when a carrier does not wash hands sufficiently well after defecation, and then serves food to others. In countries where open sewage is accessible to flies , the insects land on the sewage, pick up the bacteria, and then land on food to be eaten by humans.
Ingested bacteria head down the gastrointestinal tract, where they are taken in by cells called mononuclear phagocytes. These phagocytes usually serve to engulf and kill invading bacteria and viruses. However, in the case of S. typhi, the bacteria survive ingestion by the phagocytes, and multiply within these cells. This period of time, during which the bacteria are multiplying within the phagocytes, is the 10-14 day incubation period. When huge numbers of bacteria fill an individual phagocyte, the bacteria are discharged out of the cell and into the bloodstream, where their presence begins to cause symptoms.
The presence of increasingly large numbers of bacteria in the bloodstream (called bacteremia) is responsible for an increasingly high fever, which lasts throughout the four to eight weeks of the disease, in untreated individuals. Other symptoms include constipation (initially), extreme fatigue, headache, a rash across the abdomen known as "rose spots," and joint pain .
The bacteria move from the bloodstream into certain tissues of the body, including the gallbladder and lymph tissue of the intestine (called Peyer's patches). The tissue's inflammatory response to this invasion causes symptoms ranging from inflammation of the gallbladder (cholecystitis) to intestinal bleeding and actual perforation of the intestine. Perforation of the intestine refers to an actual hole occurring in the wall of the intestine, with leakage of intestinal contents into the abdominal cavity. This causes severe irritation and inflammation of the lining of the abdominal cavity, called peritonitis, which is frequently a fatal outcome of typhoid fever.
Other complications of typhoid fever include liver and spleen enlargement (sometimes so extreme that the spleen ruptures), anemia (low red blood cell count due to blood loss from the intestinal bleeding), joint infections (especially frequent in patients with sickle cell anemia and immune system disorders), pneumonia (due to a superimposed infection, usually by Streptococcus pneumoniae), heart infections, meningitis , and infections of the brain (causing confusion and even coma ). Untreated typhoid fever may take several months to resolve fully.
Diagnosis
Samples of a patient's stool, urine, blood, and bone marrow can all be used to culture (grow) the S. typhi bacteria in a laboratory for identification under a microscope . These types of cultures are the most accurate methods of diagnosis .
Treatment
Chloramphenicol is the most effective drug treatment for S. typhi, and symptoms begin to improve slightly after only 24-48 hours of receiving the medication. Another drug, ceftriaxone, has been used recently, and is also extremely effective, lowering fever fairly quickly.
Carriers of S. typhi must be treated even when asymptomatic, as they are responsible for the majority of new cases of typhoid fever. Eliminating the carrier state is actually a fairly difficult task, and requires treatment with one or even two different medications for four to six weeks. In the case of a carrier with gall stones, surgery may need to be performed to remove the gall bladder, because the S. typhi bacteria are often housed in the gall bladder, where they may survive despite antibiotic treatment.
Prevention
Hygienic sewage disposal systems in a community, as well as hygienic personal practices, are the most important factors in preventing typhoid fever. For travelers who expect to go to countries where S. typhi is a known public health problem, immunizations are available. Some of these immunizations provide only short term protection (for a few months), while others may be protective for several years. Immunizations which provide a longer period of protection, with fewer side effects from the vaccine itself, are being developed.
Resources
books
Berkow, Robert, and Andrew J. Fletcher. The Merck Manual ofDiagnosis and Therapy. Rahway, NJ: Merck Research Laboratories, 1992.
Cormican, M.G., and M.A. Pfaller. "Molecular Pathology of Infectious Diseases." In Clinical Diagnosis and Management by Laboratory Methods 20th ed. Philadelphia: W. B. Saunders, 2001.
Isselbacher, Kurt J., et al. Harrison's Principles of InternalMedicine. New York: McGraw Hill, 1994.
Kobayashi, G., Patrick R. Murray, Ken Rosenthal, and Michael Pfaller. Medical Microbiology. St. Louis: Mosby, 2003.
Rosalyn Carson-DeWitt
KEY TERMS
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .- Asymptomatic
—A state in which an individual experiences no symptoms of a disease.
- Bacteremia
—Bacteria in the blood.
- Carrier
—An individual who has a particular bacteria present within his/her body, and can pass this bacteria on to others, but who displays no symptoms of infection.
- Epidemic
—A situation in which a particular infection is experienced by a very large percentage of the people in a given community within a given time frame.
- Mononuclear phagocytes
—A type of cell of the human immune system which is responsible for ingesting bacteria, viruses, and other foreign matter, thus removing potentially harmful substances from the bloodstream.
Typhoid Fever
Typhoid fever
Typhoid fever is a severe infection causing a sustained high fever, and caused by the bacteria Salmonella typhi —similar to the bacteria spread by chicken and eggs resulting in "Salmonella poisoning," or food poisoning. S. typhi bacteria, however, do not multiply directly in food, as do the Salmonella responsible for food poisoning, nor does it have vomiting and diarrhea as the most prominent symptoms. Instead, persistently high fever is the hallmark of infection with Salmonella typhi.
S. typhi bacteria are passed into the stool and urine of infected patients, and may continue to be present in the stool of asymptomatic carriers (individuals who have recovered from the symptoms of the disease, but continue to carry the bacteria). This carrier state occurs in about 3% of all individuals recovered from typhoid fever.
The disease is passed between humans, then, through poor hygiene , such as deficient hand washing after toileting. Individuals who are carriers of the disease and who handle food can be the source of epidemic spread of typhoid. One such individual was the inspiration for the expression "Typhoid Mary," a name given to someone with whom others wish to avoid all contact. The real "Typhoid Mary" was a cook named Mary Mallon (1855–1938) who lived in New York City around 1900. She was a carrier of typhoid and was the cause of at least 53 outbreaks of typhoid fever.
Typhoid fever is a particularly difficult problem in parts of the world with less-than-adequate sanitation practices. In the United States, many patients who become afflicted with typhoid fever have recently returned from travel to another country, where typhoid is much more prevalent, such as Mexico, Peru, Chile, India, and Pakistan.
To cause disease, the S. typhi bacteria must be ingested. This often occurs when a carrier does not wash hands sufficiently well after defecation, and then serves food to others. In countries where open sewage is accessible to flies, the insects land on the sewage, pick up the bacteria, and then land on food to be eaten by humans.
Ingested bacteria travel down the gastrointestinal tract, where they are taken in by cells called mononuclear phagocytes. These phagocytes usually serve to engulf and kill invading bacteria and viruses . However, in the case of S. typhi, the bacteria survive ingestion by the phagocytes, and multiply within these cells. This period of time, during which the bacteria are multiplying within the phagocytes, is the 10–14 day incubation period. When huge numbers of bacteria fill an individual phagocyte , the bacteria are discharged out of the cell and into the bloodstream, where their presence begins to cause symptoms.
The presence of increasingly large numbers of bacteria in the bloodstream (called bacteremia) is responsible for an increasingly high fever, which lasts throughout the four to eight weeks of the disease, in untreated individuals. Other symptoms include constipation (initially), extreme fatigue, headache, a rash across the abdomen known as "rose spots," and joint pain.
The bacteria move from the bloodstream into certain tissues of the body, including the gallbladder and lymph tissue of the intestine (called Peyer's patches). The tissue's inflammatory response to this invasion causes symptoms ranging from inflammation of the gallbladder (cholecystitis) to intestinal bleeding and actual perforation of the intestine. Perforation of the intestine refers to an actual hole occurring in the wall of the intestine, with leakage of intestinal contents into the abdominal cavity. This causes severe irritation and inflammation of the lining of the abdominal cavity, called peritonitis, which is frequently a fatal outcome of typhoid fever.
Other complications of typhoid fever include liver and spleen enlargement (sometimes so extreme that the spleen ruptures), anemia (low red blood cell count due to blood loss from the intestinal bleeding), joint infections (especially frequent in patients with sickle cell anemia and immune system disorders), pneumonia (due to a superimposed infection, usually by Streptococcus pneumoniae), heart infections, meningitis , and infections of the brain (causing confusion and even coma). Untreated typhoid fever may take several months to resolve fully.
Samples of a patient's stool, urine, blood, and bone marrow can all be used to culture (grow) the S. typhi bacteria in a laboratory for identification under a microscope . These types of cultures are the most accurate methods of diagnosis.
Chloramphenicol is the most effective drug treatment for S. typhi, and symptoms begin to improve slightly after only 24–48 hours of receiving the medication. Another drug, ceftriaxone, has been used recently, and is extremely effective, lowering fever fairly quickly.
Carriers of S. typhi must be treated even when asymptomatic, as they are responsible for the majority of new cases of typhoid fever. Eliminating the carrier state is actually a difficult task, and requires treatment with one or even two different medications for four to six weeks. In the case of a carrier with gall stones, surgery may need to be performed to remove the gall bladder, because the S. typhi bacteria are often housed in the gall bladder, where they may survive despite antibiotic treatment.
Hygienic sewage disposal systems in a community, as well as hygienic personal practices, are the most important factors in preventing typhoid fever. For travelers who expect to go to countries where S. typhi is a known public health problem, immunizations are available. Some of these immunizations provide only short-term protection (for a few months), while others may be protective for several years. Immunizations that provide a longer period of protection, with fewer side effects from the vaccine itself, are being developed.
See also Antibody formation and kinetics; Bacteria and bacterial infection; Immunity, active, passive and delayed; Immunochemistry; Immunogenetics; Immunology; Vaccination
Typhoid
TYPHOID
Typhoid, or enteric, fever is a serious systemic disease caused by a bacillus, Salmonella typhi. Paratyphoid fever is closely related, though generally less severe. The enteric fevers have an incubation period of one to four weeks, followed by a slow onset and prolonged course, primarily affecting the gastrointestinal tract. There is a low fever and severe toxemia. A skin rash may occur in the early stages, and later other organs (liver, kidneys, bone marrow, brain) may be invaded. Typhoid is fatal in about 3 to 4 percent of cases, with higher proportions occurring where diagnostic and treatment facilities are inadequate. Diagnosis sometimes can be made clinically on the basis of patient history and physical examination, but usually depends on isolating the organism from feces or blood culture. Worldwide there are about 16 million cases annually, resulting in 600,000 deaths; in the United States there are usually less than 500 cases a year.
Typhoid is transmitted in feces—usually in polluted water, though sometimes in food that has been prepared under unhygienic conditions by a convalescent or chronic carrier. Humans are the only host for typhoid bacilli, but paratyphoid can be carried and transmitted by domestic animals. Cases continue to excrete the infective organisms in feces, and sometimes in urine, for varying periods, sometimes up to several months after apparent clinical recovery. A chronic (e.g., virtually permanent) carrier state occurs in a small number of cases; "Typhoid Mary" was a notorious example.
There may be other intermediaries between the human source and the victim who consumes contaminated water or food. For instance, water in a river estuary polluted with raw sewage containing typhoid bacilli may be ingested by shellfish or mussels, and these are then infective. It does not require a massive dose of viable typhoid bacilli to cause the disease. There are many well-documented cases of typhoid following ingestion of minuscule amounts of contaminated water or food. For instance, it suffices to eat a few lettuce leaves from a salad that was washed in contaminated water. For this reason, travelers to regions where typhoid is endemic must exercise extreme caution in what they eat and drink. All those who travel to places where typhoid occurs should also be offered prophylactic typhoid vaccine. In the past this has required several injections of vaccine, which often induced painful and sometimes unpleasantly toxic reactions. An oral vaccine is now available.
Cases of typhoid are treated with antibiotics, and notification to public health authorities is mandatory. It is rare in communities with efficient sanitary sewage disposal services and pure water supplies—the occurrence of even a single case indicates a breakdown of sanitation and hygiene in such communities, unless the disease was acquired elsewhere. A careful and complete epidemiological investigation of every case, including a detailed history of food and fluid intake, is therefore essential in order to identify the source of the infection so it can be controlled. Epidemics of typhoid rarely occur now, although they are always a potential threat when disasters such as earthquakes and floods disable sewage treatment plants. Until about the first quarter of the twentieth century, typhoid fever was endemic in all nations, and it caused the deaths of many famous people, including Albert, the consort of Queen Victoria;U.S. president Zachary Taylor; and English poet Rupert Brooke.
John M. Last
(see also: Food-Borne Diseases; Typhoid Mary; Waterborne Diseases )
typhoid
ty·phoid / ˈtīˌfoid/ (also typhoid fever) • n. an infectious fever with an eruption of red spots on the chest and abdomen and severe intestinal irritation, caused by the bacterium Salmonella typhi.DERIVATIVES: ty·phoi·dal / tīˈfoidl/ adj.