--- title: How is Shigella Infection Spread? date: 2021-01-04T20:29:00-08:00 author: admin canonical_url: "https://marlerclark.com/foodborne-illnesses/shigella/shigella-transmission" section: Resource Library --- [Foodborne Illnesses](/foodborne-illnesses) / [Shigella](https://marlerclark.com/foodborne-illnesses/shigella) / # How is Shigella Infection Spread? ### Human cases of *Shigella* are typically acquired through contact with infected persons or ingestion of food contaminated with *Shigella* bacteria. ![](https://s3.us-west-2.amazonaws.com/aboutshigellacom-images/outbreaks/image3.jpeg)As previously noted, *Shigella* species are transmitted by the fecal-oral route, and most infections are transmitted from person to person, reflecting the low infectious dose. As few as ten *Shigella* bacteria can result in clinical infection. Where persons who are infected may be present, the risk of transmission and infection increases with poor hand hygiene, ingestion of contaminated food or water, inadequate sanitation and toileting, overcrowding, and sexual contact. *Shigella* bacteria are present in the stools of infected persons while they are sick, and for up to a week or two afterwards. It has been estimated that up to 80% of all infections are the result of person-to-person transmission. ![](https://s3.us-west-2.amazonaws.com/aboutshigellacom-images/outbreaks/image4.jpeg)Because of its quite common person-to-person spread, shigellosis has long been associated with outbreaks in daycare centers, nursing homes, institutional settings (*e.g.*, prisons), and cruise ships. Explaining the significance of daycare centers as a source of *Shigella* infection, one well-respected study explains as follows: > High shigellosis rates in children are attributable to several factors. Young children are unable to practice good personal hygiene and have not yet acquired immunity to *S. sonnei*. The infectious dose is as low as 10–200 organisms, and person-to-person transmission is highly effective. Day-care centers play an important role in the person-to-person spread of shigellosis and its subsequent dissemination in communities. Inadequate hand washing, diapering practices, and fecal contamination of water-play areas, such as kiddie pools, have been associated with *S. sonnei* transmission in day-care centers. *Shigella* infections also may be acquired from eating contaminated food. Studies estimate that approximately one-third of U.S. shigellosis cases annually might be caused by the consumption of contaminated food. In the United States, incidence of foodborne illness is documented through FoodNet, a reporting system used by public health agencies that captures foodborne illness in 15% of the population. Of the 10 pathogens tracked by FoodNet, *Salmonella*, *Campylobacter*, and *Shigella* are responsible for most cases of foodborne illness. An estimated 35% of the total number of cases of shigellosis involved food as the vehicle of transmission. ![](https://s3.us-west-2.amazonaws.com/aboutshigellacom-images/outbreaks/image5.jpeg?1615529514200)According to the CDC, *Shigella* is the third most common pathogen transmitted through food. In [FoodNet surveillance areas](http://www.cdc.gov/foodnet/surveillance.html) in 2015, the rate of *Shigella* was 5.4 per 100,000 population, exceeded only by [*Salmonella*](http://www.about-salmonella.com/) (15.7/100,000) and [*Campylobacter*](http://www.about-campylobacter.com/) (12.8/100,000). In 2019, FoodNet identified approximately 26,000 cases of foodborne infections, 2,500 of which were attributed to *Shigella*; only 0.1% of those illnesses resulted in death, which is the lowest reported percentage of the bacterial foodborne pathogens. [ Next: Symptoms of Shigella Infection › ](https://marlerclark.com/foodborne-illnesses/shigella/shigella-symptoms-risks) ### More information about Shigella [February 26, 2020 ###### Mariscos San Juan Restaurant Shigella Outbreak and Litigation - California (2015) According to a Public Health Warning, on Saturday afternoon, October 17, 2015, the Santa Clara County Public Health Department was notified by a local hospital of 5 patients with fever ... ](https://marlerclark.com/news_events/mariscos-san-juan-restaurant-shigella-outbreak-and-litigation-california-2015) [February 11, 2018 ###### Pearl Catering Shigella Outbreak Lawsuits - Oregon (2018) On August 14, 2018 the Oregon Health Authority (OHA) and Yamhill County Health and Human Services received reports of multiple people with gastrointestinal illness days after attending a wedding and ... ](https://marlerclark.com/news_events/pearl-catering-shigella-outbreak-and-litigation-oregon-2018) [November 05, 2014 ###### Salsarita Shigella Outbreak Lawsuit – Arkansas (2014) Salsarita’s Restaurant in the Walmart Home Office Café in Bentonville has reopened following a Shigella outbreak that made 275 sick in nine states. ... ](https://marlerclark.com/news_events/salsarita-shigella-outbreak-lawsuit-arkansas-2014) [March 08, 2010 ###### Subway Restaurant Shigella Outbreak Lawsuits - Illinois (2010) At least 116 people were confirmed ill with Shigella infections traced to a Subway restaurant in Lombard, IL in March of 2010. Marler Clark represented 74 people sickened in this ... ](https://marlerclark.com/news_events/subway-restaurant-shigella-outbreak-chicago) [1. View all ](/news_events/outbreaks?illness=shigella&year=all) ## All Shigella Resources [###### Shigella Food Poisoning ](https://marlerclark.com/foodborne-illnesses/shigella/about-shigella) [###### The Incidence of Shigella Infection ](https://marlerclark.com/foodborne-illnesses/shigella/shigella-incidence) [###### The Prevalence of Shigella in Food and Elsewhere ](https://marlerclark.com/foodborne-illnesses/shigella/shigella-prevalence) [###### How is Shigella Infection Spread? ](https://marlerclark.com/foodborne-illnesses/shigella/shigella-transmission) [###### Symptoms of Shigella Infection ](https://marlerclark.com/foodborne-illnesses/shigella/shigella-symptoms-risks) [###### Complications of Shigella Infection ](https://marlerclark.com/foodborne-illnesses/shigella/shigella-complications) [###### How is Shigellosis Diagnosed? ](https://marlerclark.com/foodborne-illnesses/shigella/shigella-diagnosis) [###### Treatment for Shigella Infection ](https://marlerclark.com/foodborne-illnesses/shigella/shigella-treatment) [###### The Economic Impact of Shigella Infections ](https://marlerclark.com/foodborne-illnesses/shigella/shigella-economic-impact) [###### How to Prevent Shigella Infection ](https://marlerclark.com/foodborne-illnesses/shigella/shigella-prevention) [###### Outbreaks of Shigella Infection ](https://marlerclark.com/foodborne-illnesses/shigella/shigella-outbreaks) [###### Antimicrobial Resistance in Bacteria ](https://marlerclark.com/foodborne-illnesses/shigella/antimicrobial-resistance-in-bacteria-shigella) [###### Shigella References ](https://marlerclark.com/foodborne-illnesses/shigella/shigella-references) ### Other foodborne illnesses [E. coli](https://marlerclark.com/foodborne-illnesses/e-coli) [Salmonella](https://marlerclark.com/foodborne-illnesses/salmonella) [Listeria](https://marlerclark.com/foodborne-illnesses/listeria) [Hepatitis A](https://marlerclark.com/foodborne-illnesses/hepatitis-a) [Reactive Arthritis](https://marlerclark.com/foodborne-illnesses/reactive-arthritis) [Guillain-Barre Syndrome](https://marlerclark.com/foodborne-illnesses/guillain-barre-syndrome) [Irritable Bowel Syndrome](https://marlerclark.com/foodborne-illnesses/irritable-bowel-syndrome) [Norovirus](https://marlerclark.com/foodborne-illnesses/norovirus) [Botulism](https://marlerclark.com/foodborne-illnesses/botulism) [Campylobacter](https://marlerclark.com/foodborne-illnesses/campylobacter) [Cyclospora](https://marlerclark.com/foodborne-illnesses/cyclospora) [Hemolytic Uremic Syndrome](https://marlerclark.com/foodborne-illnesses/hemolytic-uremic-syndrome)