The term Salmonella refers to a group or family of bacteria that variously cause illness in humans. Salmonella serotype typhimurium and Salmonella serotype enteritidis are the most common in the United States. Salmonella has been known to cause illness for over 100 years. Salmonella javiana is the fifth most common serotype in the United States and accounted for 3.4% of Salmonella isolates reported to the CDC during 2002. See “Outbreak of Salmonella serotype javiana infections—Orlando, Florida, June 2002,” MMWR Weekly, August 9, 2002/51(31); 683-84. And of the Salmonella outbreaks that occurred from 1985 through 1999, “[f]ive hundred twenty-two (62%) outbreaks of S. Enteritidis infection were associated with food prepared at commercial food establishments (restaurants, caterers, delicatessens, bakeries, cafeteria, or market).” See Patrick ME, et al. “Salmonella Enteritidis infections, United States, 1985–1999,” Emerg Infect Dis [serial online] 2004.
Where Does Salmonella Come From?
Salmonella is an enteric bacterium, which means that it lives in the intestinal tracts of humans and other animals, including birds. Salmonella bacteria are usually transmitted to humans by eating foods contaminated with animal feces or foods that have been handled by infected food service workers who have practiced poor personal hygiene. Contaminated foods usually look and smell normal. Contaminated foods are often of animal origin, such as beef, poultry, milk, or eggs, but all foods, including vegetables, may become contaminated. Many raw foods of animal origin are frequently contaminated, but thorough cooking kills Salmonella. The food handler who neglects to thoroughly wash his or her hands with soap and warm water after using the bathroom may contaminate foods that have otherwise been properly prepared.
What are the Symptoms of Salmonellosis?
Once in the lumen of the small intestine, the bacteria penetrate the epithelium, multiply, and enter the blood within 24 to 72 hours. Variables such as the health and age of the host and virulence differences among the serotypes affect the nature of the diagnosis. Infants, the elderly, individuals hospitalized, and the immune-suppressed are the populations that are the most susceptible to disease and suffer the most severe symptoms.
“The majority of persons infected with Salmonella have diarrhea, fever, and abdominal cramps 12-72 hours after exposure. The illness usually lasts 4-7 days, and the majority of persons recover without treatment.” MMWR Weekly, supra at 684. The acute symptoms of Salmonella gastroenteritis include the sudden onset of nausea, abdominal cramping, and bloody diarrhea with mucous. As already noted, there is no real cure for a Salmonella infection; treatment, therefore, tends to be palliative – although prescription of antibiotics is common, even if usually contraindicated.
Medical treatment is acutely important if the patient becomes severely dehydrated or if the infection spreads from the intestines. Persons with severe diarrhea often require re-hydration, usually with intravenous fluids. Antibiotics are not necessary or indicated unless the infection spreads from the intestines, and then it can be treated with ampicillin, gentamicin, trimethoprim/sulfamethoxazole, or ciprofloxacin. Unfortunately, some Salmonella bacteria have become resistant to antibiotics, largely as a result of the use of antibiotics to promote the growth of feed animals.
Medical Complications that can arise from a Salmonella Infection
People infected with Salmonella usually recover without medical treatment in six to ten days. It may be several months, however, before their susceptibility to diarrhea and gastrointestinal distress disappears. “Although younger individuals usually face far higher infection rates from these pathogens, older adults are more likely to have more severe complications.” See J. Busby, “Older Adults at Risk of Complications from Microbial Foodborne Illness,” Food Review, Vol. 25, Issue 2, pp. 30-35, at 32, Summer-Fall, 2002. In addition, “the elderly are far more susceptible to death from Salmonella infections than the general population.” Id.
Several bacteria, including Salmonella, induce septic arthritis. See J. Lindsey, “Chronic Sequellae of Foodborne Disease,” Emerging Infectious Diseases, Vol. 3, No. 4, Oct-Dec, 1997. The resulting joint pain and inflammation can resolve completely over time or permanent joint damage can occur. Id. In a small number of persons, the joint inflammation is accompanied by conjunctivitis (inflammation of the eyes), and uveitis (painful urination). Id. This triad of symptoms is called Reiter’s Syndrome. Id. Reiter’s Syndrome is a special form of reactive arthritis, autoimmune disorder triggered by the Salmonella infection. It occurs in persons with a genetic predisposition and can last for a year or more. Antibiotic treatment does not make a difference in whether or not the person later develops arthritis.