Typhoid fever, caused by S. typhi, is spread by fecal contamination of water or milk or by food handlers who are carriers. It is characterized by a high fever and a rash on the chest and abdomen and can be fatal. Paratyphoid fever, caused by S. paratyphi, is also spread in the feces of victims or carriers. Outbreaks often occur where adequate hygiene, especially in food preparers, is not practiced. Paratyphoid is characterized by mild fever and a rash on the chest. Bacteremia is characterized by the presence of S. choleraesuis, S. typhimurium, or S. heidelberg in the blood. All three diseases are treated with the antibiotic chloramphenicol.
The most common form of salmonellosis is food poisoning caused by S. typhimurium and other Salmonella species. Sources of infection include eggs, beef, poultry, unpasteurized dairy products, and fruits and vegetables. In 1998 a new product called CF-3, or Preempt, which could reduce but not eliminate Salmonella in chickens, was approved for sale to poultry farmers. Delivered as a spray to newly hatched chicks, it consists of a mixture of beneficial bacteria that the mother hen normally transferred to her chicks before the advent of factory farms.
Outbreaks of salmonellosis food poisoning occasionally result from contaminated institutional or other mass-prepared food. In the home the bacteria can spread via contaminated cooking areas. Carriers and household pets, especially pet reptiles, can also spread the disease. Symptoms arise 6 to 72 hours after exposure and include severe diarrhea, fever and chills, vomiting, and abdominal cramps. Symptoms usually last three to five days.
See also food poisoning.
Any of several bacterial infections caused by salmonella, including typhoid and similar fevers and gastroenteritis (see food poisoning). Meat from diseased animals carries the bacteria, and any food can pick it up from infected feces in the field or during storage or from contaminated food or utensils during food preparation. The source is often hard to trace. Eggs from infected hens can carry it within, not just on the shells. Onset is sudden and sometimes severe, with nausea, vomiting, diarrhea, fatigue, and low fever. Most patients recover within days, with some degree of immunity. Prevention requires care in food handling, especially thorough cooking.
Learn more about salmonellosis with a free trial on Britannica.com.
Salmonellosis is an infection with Salmonella bacteria. Most persons infected with Salmonella develop diarrhea, fever, vomiting, and abdominal cramps 12 to 72 hours after infection. In most cases, the illness lasts 3 to 7 days—most affected persons recover without treatment. However, in some persons the diarrhea may be so severe that the patient becomes dangerously dehydrated and must be taken to a hospital. At the hospital, the patients may receive intravenous fluids to treat their dehydration and medications may be given to provide symptomatic relief, like fever reduction. In severe cases, the Salmonella infection may spread from the intestines to the blood stream, and then to other body sites and can cause death unless the person is treated promptly with antibiotics. The elderly, infants, and those with impaired immune systems are more likely to have a severe illness. Some people afflicted with Salmonellosis later experience reactive arthritis, which can have long-lasting, disabling effects.
The type of salmonella usually associated with infections in humans is called Non-Typhoidal Salmonella. It is usually contracted by ingesting raw or undercooked eggs, or from sources such as:
A rarer form of salmonella called typhoidal salmonella can lead to typhoid fever. It is only carried by humans and is usually contracted through direct contact with the fecal matter of an infected person. It therefore mainly occurs in countries that do not have proper systems for handling human waste.
The U.S. Government reported that as many as 20% of all chickens were contaminated with salmonella in the late 1990s, and 16.3% were contaminated in 2005. In the mid to late twentieth century, Salmonella enterica serovar Enteritidis was a common contaminant of eggs. This is much less common now with the advent of hygiene measures in egg production and the vaccination of laying hens to prevent salmonella colonization. Many different salmonella serovars also cause severe diseases in animals other than human beings.
In February 2007, the U.S. FDA issued a warning to consumers not to eat certain jars of Peter Pan peanut butter or Great Value peanut butter due to risk of contamination with 'Salmonella Tennessee'.
In March 2007, around 150 people were diagnosed with salmonella-poisoning after eating tainted food at a governor's reception in Krasnoyarsk, Russia. Over 1,500 people attended the ball on March 1 and fell ill as a consequence of ingesting salmonella-tainted sandwiches.
As of July 8, 2008, from April 10, 2008, the rare Saintpaul serotype of Salmonella enterica caused at least 1017 cases of salmonellosis food poisoning in 41 states throughout the United States, the District of Columbia, and Canada. As of July 2008, the U.S. Food and Drug Administration suspects that the contaminated food product is a common ingredient in fresh salsa, such as raw tomato, fresh jalapeño pepper, fresh serrano pepper, and fresh cilantro. It is the largest reported salmonellosis outbreak in the United States since 1985. New Mexico and Texas have been proportionally the hardest hit by far, with 49.7 and 16.1 reported cases per million, respectively. The greatest number of reported cases have occurred in Texas (384 reported cases), New Mexico (98), Illinois (100), and Arizona (49). There have been at least 203 reported hospitalizations linked to the outbreak, it has caused at least one death, and it may have been a contributing factor in at least one additional death. The CDC maintains that "it is likely many more illnesses have occurred than those reported." If applying a previous CDC estimated ratio of non-reported salmonellosis cases to reported cases (38.6:1), one would arrive at an estimated 40,273 illnesses from this outbreak.
As of 18 July 2008, the FDA removed raw tomatoes and cilantro as potential carriers, however fresh jalapeño peppers and fresh serrano peppers still remain..
The law was enacted, according to the FDA, "because of the public health impact of turtle-associated salmonellosis". There had been reported cases of young children placing small turtles in their mouths, which led to the size-based restriction.