Shigellosis is an infection of the intestines caused by Shigella bacteria.


Shigella is transmitted through the fecal-oral route of individuals infected with the disease, whether or not they are exhibiting symptoms.


Most cases occur in the developing world.


A more common and serious condition in the developing world;


((Shigella)) causes about 580,000 cases annually among travelers and military personnel from industrialized countries.


An estimated 500,000 cases of shigellosis occur annually in the United States.


Symptoms of shigellosis generally start one to two days after exposure.


Symptoms include: diarrhea, fever, abdominal pain, and feeling the need to pass stools even when the bowels are empty,cramps, slimy stools, blood, pus, or mucus in stools or tenesmus.


The associated diarrhea may be bloody.


Shigellosis symptoms typically last five to seven days.


It may take several months before bowel habits return entirely to normal.


Complications of shigellosis include: reactive arthritis, sepsis, seizures, and hemolytic uremic syndrome.


Diagnostic methods by stool culture.


Frequency greater than 80 million cases with  700,000 deaths annually, globally.


About half a million cases occur a year in the US.


Shigellosis is caused by four specific types of Shigella.


Spread by exposure to infected feces, via contaminated food, water, or hands or sexual contact.


Contamination may be spread by flies or when changing diapers..


No vaccine exists.


The risk of infection can be reduced by properly washing the hands.


It usually resolves without specific treatment, but sufficient fluids by mouth and rest is recommended.


Medications that slow the bowels are not recommended.


In severe cases antibiotics may be used: ciprofloxacin and azithromycin.


Antibacterial resistance  is common.


Young children are most commonly affected, due to uutbreaks of disease in childcare settings and schools.


Shigellosis is also relatively common among travelers.


Onset time is 12 to 96 hours, and recovery takes 5 to 7 days.


Shigellosis infections may be associated with mucosal ulceration, rectal bleeding, and severe  dehydration. 


Possible sequelae  of shigellosis are arthritis and hemolytic uremic syndrome, and seizures.


Shigellosis is caused by a bacterial infection with Shigella: 


Shigella flexneri


Shigella boydii


Shigella dysenteriae and


Shigella sonnei 


S. sonnei is the most common in the United States, while S. dysenteriae and S. boydii are rare in the U.S.


Ingested bacteria reach the small intestine where they begin to multiply until they reach the large intestine.


In the large intestine Shigella bacteria cause cell injury by direct invasion of epithelial cells in the large intestine and production of enterotoxin 1 and enterotoxin 2.


Shigella is not destroyed by the gastric acid, and it takes only 10 to 200 cells to cause an infection.


This infectious dose is several order of magnitudes smaller than that of other species of bacteria.


Sexually transmitted shigellosis is resistant to multiple antimicrobial agents.


The diagnosis of shigellosis is made by isolating and identifying the organism from fecal culture samples.


Most Shigella species are negative for motility and are  not lactose fermenters.


Shigella species typically do not produce gas from carbohydrates, and tend to be overall biochemically inert. 


To prevent getting shigellosis: washing hands before handling food and thoroughly cook all food before eating. 


Primary prevention methods are improved sanitation and personal and food hygiene, 


No vaccine targeting Shigella exists. 


Treatment consists mainly of replacing fluid  and salt replacement  because of diarrhea. 


Oral replacement efforts mouth is satisfactory for most patients.


In severe disease some may need to receive fluids intravenously. 


Antidiarrheal drugs may prolong the infection and should not be used.


Antibiotics are used only be used in severe cases or for patients with mild symptoms but are elderly, immunocompromised, food service industry workers, or child care workers.


Shigella-associated diarrhea, antibiotics shorten the length of infection.


Antibiotics are usually avoided in mild shigellosis because many strains are becoming resistant to common antibiotics.


The disease resolves within four to eight days without antibiotics, in most shigellosis cases.


Severe cases of shigellosis infections may last three to six weeks: Infants, the elderly, and the critically ill are susceptible to the most severe symptoms of disease.


When antibiotics, are used as trimethoprim-sulfamethoxazole, ciprofloxacin may be given:  in the very young, very old, when the disease is severe, or when the risk of the infection spreading to other people is high. 


Patients with acquired immune deficiency syndrome (AIDS) are more frequently infected with Shigella.


Mortality rates of shigellosis epidemics in developing countries can be as high 5–15%.


Orthodox Jewish communities (OJCs) are a known risk group for shigellosis in Israel, due to Shigella sonnei.



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