salmonellosis

Salmonellosis is an infection with Salmonella bacteria. Most people who get 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.[1] 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 from sources such as:

• Poultry, pork, and cattle, if the meat is prepared incorrectly or somehow becomes infected with the bacteria.^[1]
• Infected eggs and milk, as well as egg products, when not prepared, handled, or refrigerated properly.^[1]
• Reptiles such as turtles, lizards, and snakes, as they can carry the bacteria on their skin.
• Pet rodents
• Tainted fruits and vegetables^[1]

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 advanced systems for handling human waste.

Etymology

Both Salmonellosis and the Salmonella genus of microorganisms derive their names from a modern Latin coining after Daniel E. Salmon (1850–1914), an American veterinary surgeon. He had help from Theobald Smith, and together they found the bacterium in pigs.

Symptoms

The bacterium induces responses in the animal that it is infecting, and this is what typically causes the symptoms, rather than any direct toxin produced. Symptoms are usually gastrointestinal, including nausea, vomiting, abdominal cramps and bloody diarrhea with mucus. Headache, fatigue and rose spots are also possible. These symptoms can be severe, especially in young children and the elderly. Symptoms last generally up to a week, and can appear 12 to 72 hours after bacterium ingestion.

After bacterial infections, reactive arthritis (a.k.a. Reiters syndrome) can develop.^[2] In sickle-cell anemia, osteomyelitis due to Salmonella infection is much more common than in the general population. Note however, salmonella infection is more frequently the cause of osteomyelitis in sickle-cell anemia patients, not the most common cause. The most common cause of osteomyelitis remains due to staphylococcus infection.

Incidents of salmonellosis

The examples and perspective in this section deal primarily with the United States and do not represent a worldwide view of the subject. Please improve this article and discuss the issue on the talk page. (April 2009)

About 142,000 Americans are infected each year with Salmonella enteritidis from chicken eggs, and about 30 die.^[3]

Up to 2005

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.^[4] 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.

2006

In June 2006, the BBC reported that the Cadbury chocolate manufacturer withdrew a number of products when products contaminated with Salmonella resulted in up to 56 cases of salmonellosis.^[5] The causes had been traced to a leaking pipe at a Cadbury plant in Herefordshire in January 2006, though the announcement was not made until June.

2007

In February 2007, the U.S. Food and Drug Administration (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 S. Tennessee. [2]

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.

In December 2007, about 150 people were sickened by salmonella-tainted chocolate cake produced by a major bakery chain in Singapore. [3]

2008

From April 10, 2008 to July 8, 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).^[6] 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.^[7] 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.^[8]

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.^[9]

In December 2008 and January 2009, several Midwestern states, including Ohio (officially confirmed by state authorities), reported an outbreak of salmonellosis from Salmonella typhimurium that had sickened at least 50 people, due to contaminated dairy products like cheeses.^{[citation needed]}

2009

On January 17, 2009, the FDA announced they had traced the source of an outbreak of Salmonella typhimurium to a plant in Blakely, Georgia, owned by Peanut Corporation of America (PCA), and urged people to postpone eating commercially-prepared or manufactured peanut butter-containing products and institutionally-served peanut butter.^[10] Salmonella was reported to be found in 46 states in the United States in at least 3,862 peanut butter-based products such as crackers, energy bars, and peanut butter cookies from at least 343 food companies. Dog treats were affected as well. At least 691 people in more than 46 states became sick, and the Salmonella claimed at least nine lives as of March 25.^{[11][12][13][14][15]}

Peanut butter and peanut paste manufactured by PCA were distributed to hundreds of firms for use as an ingredient in thousands of different products, such as cookies, crackers, cereal, candy and ice cream, all of which were recalled. Some products were also sold directly to consumers in retail outlets like dollar stores^[10]

On March 14, 2009, expressing his own personal concern for the safety of his children who enjoy peanut butter, President Obama announced the establishment of the Food Safety Working Group, "an interagency effort to help overhaul the oversight system." ^[16] The announcement came days after the FDA, also responding, released its first "guidance" on dealing with salmonella contamination.

Four-Inch Regulation

The "Four-Inch Regulation" or "Four-Inch Law" is a colloquial name for a regulation issued by the U.S. Food and Drug Administration in 1975, restricting the sale of turtles with a carapace length of less than four inches. Exceptions are provided for scientific and educational use, export, and private sale.^[17]

The regulation was promulgated, 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.

Prevention

The FDA has published guidelines^[18] to help reduce the chance of food-borne salmonellosis. Food must be cooked to 68°C - 72°C (145°F - 160°F) and liquids like soups or gravies must be boiled. Freezing is not sufficient to kill Salmonella. While Salmonella is usually heat-sensitive, the same doesn't apply in high-fat environments.^[19]

Antibodies and vaccine development

Salmonella antibodies were first found in Malawi children in research published in 2008. The Malawian researchers have identified an antibody that protects children against bacterial infections of the blood caused by Salmonella. A study of 352 children at Blantyre's Queen Elizabeth hospital found that children up to two years old develop antibodies that aid in killing the bacteria. The researchers proposed that this could lead to a possible Salmonella vaccine.^[20]

See also

• 1984 Rajneeshee bioterror attack
• Typhoid fever
• List of foodborne illness outbreaks

References

External links

Wikimedia Commons has media related to: Salmonella

• CDC website, Division of Bacterial and Mycotic Diseases, Disease Listing: Salmonellosis
• CFIA Website: Salmonellae
• Protective salmonella antibodies found in Malawi children, Sub-Saharan Africa gateway, Science and Development Network, [4]