Shigella is a highly contagious and virulent bug that is commonly the culprit in outbreaks at schools and other institutional settings.  Shigella outbreaks are frequently caused by the fecal-oral route, whether the route of ultimate transmission be food or contact with surfaces contaminated by the bacteria.  This means that bacteria from the stool of an

There’s a bacterial infection making the rounds in the Hub City. Shigellosis is the result of a battle of bacteria. Due to an increasing number of gastrointestinal illnesses, the Lubbock Health Department is trying to spread the word about this nasty germ. It’s not uncommon for an outbreak this time of year, but the jump

Shigella was the third most common food-borne illness in the United States during 2008, according to the Foodborne Diseases Active Surveillance Network (FoodNet) of CDC’s Emerging Infections Program, which collects data from 10 U.S. states.

The number of infections and incidence per 100,000 population were reported as follows:

  • Salmonella (7,444; 16.20),
  • Campylobacter (5,825; 12.68),
  • Shigella

Shigella is a bacterium that belongs to a small group of pathogens (including E. coli O157:H7 and Cryptosporidium) that can infect the gut after the ingestion of relatively few organisms, and can cause sudden and severe diarrhea (gastroenteritis) in humans.  When ingested, Shigella bacteria penetrate the lining of the intestine, causing swelling and possibly causing sores to develop (Mayo Clinic, 2007, April 14).

Volunteer experiments have demonstrated that shigellosis – the illness caused by the ingestion of Shigella bacteria, which is also known as “bacillary dysentery” – can occur after ingestion of fewer than 200 bacteria (DuPont, et. al. 1989), making Shigella one of the most communicable and severe forms of the bacterial-induced diarrheas (Gomez, et.al. 2002).

Shigella is named after Kiyoshi Shiga, a Japanese scientist who discovered Shigella dysenteriae type 1 in 1896 during a large epidemic of dysentery in Japan (Keusch & Acheson, 1996).  Since that time, several types of Shigella bacteria have been discovered – S. dysenteriae, S. flexneri, S. boydii, and S. sonnei – all named after the lead workers who discovered them (CDC, 2005, October 13).

Shigella thrives in the human intestine and is commonly spread both through food and by person-to-person contact.  About 25,000 laboratory-confirmed cases of shigellosis are reported each year in the U.S. (Mead, et al., 1999); however, many cases go undiagnosed and/or unreported and the Centers for Disease Control and Prevention (CDC) estimates that 450,000 total cases of shigellosis occur in the United States every year (Baer, et al., 1999; CDC, 2005, October 13).

No group of individuals is immune to shigellosis, but certain individuals are at increased risk. Small children acquire Shigella at the highest rate. Persons infected with HIV experience shigellosis much more commonly than other individuals, but this may largely be due to an increased risk among men having sex with men (Baer, et al., 1999).

In developing countries, S. flexneri is the most predominant cause of shigellosis, but S. dysinteriae type 1 is the most frequent cause of epidemic and endemic disease.  In developed countries such as the United States, S. sonnei is the predominant cause of Shigellosis; S. sonnei is involved in over 75% of cases reported annually in the US (Keusch & Acheson, 1996).


Continue Reading What is Shigella?

Oct 19, 2005, 03:09 AM
Parent Reaction to Local Shigellosis Cases
2 Local Confirmed Cases of Shigellosis
The Jackson County Health Department says they have two new cases of shigellosis. Two kids have contracted the contagious virus that causes vomiting, fever, stomach cramps and diarrhea. You’ll remember last school year, more than 100 Ingham County kids and 67 Jackson residents came down with the virus. Health officials say it’s too early determine if the problem will be of similar proportions this year.


Continue Reading Parent Reaction to Local Shigellosis Cases

July 28, 2005
Lexington Herald-Leader
Barbara Isaacs
http://www.kentucky.com/mld/kentucky/12248332.htm
Dr. Melinda Rowe, commissioner of the Lexington-Fayette , Kentucky, County Health Department, was cited as saying that Fayette Countyís ongoing shigellosis outbreak is no longer just related to kids sickened in day care, adding, “This is a community-wide outbreak going on. Itís probably going to get worse before it gets better.”
The story notes that the number of confirmed shigellosis cases has doubled during the past month, bringing the total since May to 111.
A month ago, the vast majority of shigella infections ó 49 of 55 cases ó were among children 4 and under who attend day care.


Continue Reading Shigellosis outbreak spreads

By Pam Mellskog
The Daily Times-Call
LONGMONT ó Tossing cow pies in a public pool after hours seemed like fun for somebody in CaÒon City several summers back.
The culprit likely hoped the fecal patties floating like ugly lily pads overnight would shock and disgust pool staff and swimmers.
But the prank backfired and created the worst outbreak of cryptosporidium ó ìcryptoî for short ó in recent Colorado history, said Glenn Bodnar, a drinking water expert with years of swimming pool experience at the Colorado Department of Public Health and Environment.
State regulations mandate public pools to filter all their water, which could be tens of thousands of gallons, at least once every six hours.
That process, he said, dissolved the offending fecal flotsam in the CaÒon City pool by the time the doors opened. However, the pool water that day was still teeming with crypto, Bodnar said.


Continue Reading Balancing Act: To disinfect, pools must have the right amount of chlorine, ph levels