News / Europe

E coli: Good Bacteria Gone Bad

Outbreak in Europe focuses attention on deadly strain

Samples are taken from a cucumber for a molecular biological test in Brno, Czech Republic on Wednesday, June 1, 2011.
Samples are taken from a cucumber for a molecular biological test in Brno, Czech Republic on Wednesday, June 1, 2011.

Multimedia

Audio

As a major outbreak of a highly toxic strain of E. coli bacteria continues to sicken residents of Europe, medical experts are racing to find the source.

E. coli has become a growing public health problem in recent years. The bacteria doesn't usually cause any trouble, says University of Minnesota microbiology professor Michael Sadowski. "E. coli is a normal inhabitant of the intestinal tract of warm-blooded animals."

That means you, me, our livestock and even wild animals are all carrying strains of E. coli around in our guts. The types that cause disease are rare, Sadowski says.

"The majority of E. coli are in fact considered to be harmless. And they carry out various biochemical processes in your intestine and they help you digest food."

E. coli and how it is transmitted

E. coli is an abbreviation for Escherichia, which is a large and diverse group of bacteria. Most strains are harmless, others can cause illness. Symptoms include stomach cramps, diarrhea and vomiting. The major source is cattle, but other animals, foods and liquids may spread contamination to people.

  • Shiga toxin-producing E. coli

    This is a dangerous form of E. coli known by the acronym STEC. The best known strain of this STEC (also called 0157) was identified in 1982. Transmission and symptoms are similar to the most common form of E. coli.

  • EHEC

    A very serious infection is enterohaemorrhagic E. coli known by the acronym EHEC. It produces toxins, known as verotoxins or Shiga-like toxins. It may lead to life threatening diseases such as hemolytic uremic syndrome, or HUS.

  • HUS

    Scientists believe this is responsible for the European outbreak, originating from a potentially life threatening strain of STEC (0104). HUS afflicts the kidneys, blood and central nervous system.

And the majority have remained relatively harmless until fairly recently, says University of Minnesota food safety professor Francisco Diez. "We didn't have this type of organism before 1982."

That's when the first deadly strain of E. coli appeared in hamburger meat in the United States. Before then, Diez says, E. coli wasn't even considered a disease-causing germ.

According to Diez, it is not clear exactly how this new virulence developed. It may have been changes in the bacteria, or changes in the way food is produced or distributed. Whatever the cause, E. coli is now turning up in a growing number of fruits and vegetables including apples, lettuce, and spinach.

For a germ that was first found in meat, it seems like a long way to the produce aisle. But Diez says there is a connection.


"We've seen an increase in cases of produce-associated outbreaks, but ultimately the source is cattle."

He says cattle-manure fertilizer that has not been well composted may still carry live bacteria from the animals’ gut. Or manure may contaminate irrigation water. It could also be on the hands of someone picking or sorting the produce. Add storage, transportation, and preparation as other places between the farm and the fork where food can become contaminated with the bacteria.

That's part of why tracing an outbreak to its source is so difficult. In Europe, officials originally blamed Spanish-grown cucumbers, but now they are not so sure. Other suspects include tomatoes and lettuce.

The problem is, those are all common salad ingredients.

"It's hard to find enough people that only ate one, and only ate one once in the time period before their infection," says Christopher Braden, head of the foodborne disease section at the U.S. Centers for Disease Control and Prevention." They're commonly eaten. They're commonly eaten together. So to try to tease one apart as to which one is the culprit can be difficult."

Spain maintains that its cucumbers have been falsely accused. Spanish farmers are losing huge amounts of money, and they are furious.

The CDC was in a similar position in 2008 when it blamed tomatoes for a salmonella outbreak that ultimately was pinned on peppers.

Braden says it can be a hard decision to make when you have preliminary information that points to a suspect. "And in the meantime, people are getting ill and possibly dying in large numbers. Sometimes there's a real balancing act between being fast and being right. Often times it's really hard to do both."

He adds that, if their first suspicions proved correct, they could also be criticized if they did not act.

There are still a lot of unknowns about the current European outbreak, and it will likely be some time before they are all resolved.

In the meantime, the advice remains the same: wash your hands after using the toilet, and before preparing food and eating, and wash counters and utensils that come in contact with raw meat.

And if you are concerned about the cleanliness of raw vegetables, cook them well.

You May Like

Obama: I Will Do 'Everything I Can' to Close Guantanamo

US president says prison continues 'to inspire jihadists and extremists around the world' More

Sierra Leone Educates on Safe Ebola Burials

Also, country is improving at rapid response to isolated outbreaks, but health workers need to be even faster, officials say More

Religion Aside, Christmas Gains Popularity in Communist Vietnam

Increasingly wealthy Vietnamese embrace holiday due to its non-religious glamor, commercial appeal More

This forum has been closed.
Comments
     
There are no comments in this forum. Be first and add one

Featured Videos

Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
US Decision on Cuba Underscores Divisions Among Miami Cubansi
X
Sharon Behn
December 19, 2014 9:34 PM
For decades, older, more conservative Cubans have been gathering at Café Versailles on the corner of Calle Ocho to eat Cuban food and talk politics. After hearing of President Barack Obama’s decision, a number of them gathered in front of the café with posters to protest. VOA's Sharon Behn reports on the situation.
Video

Video US Decision on Cuba Underscores Divisions Among Miami Cubans

For decades, older, more conservative Cubans have been gathering at Café Versailles on the corner of Calle Ocho to eat Cuban food and talk politics. After hearing of President Barack Obama’s decision, a number of them gathered in front of the café with posters to protest. VOA's Sharon Behn reports on the situation.
Video

Video Three Cities Bid for Future Obama Presidential Library

President Barack Obama still has two years left in his term in office, but the effort to establish his post-presidential library is already underway. The bid for the Obama Presidential Library is down to four locations in three states -- New York, Hawaii, and Illinois. As VOA’s Kane Farabaugh reports, each of them played an important part in the president’s life before he reached the White House.
Video

Video Cuba Deal is Major Victory for Pope’s Diplomatic Initiatives

Pope Francis played a key role in brokering the US-Cuba deal that was made public earlier this week. It is the most stunning success so far in a series of peacemaking efforts by the pontiff. VOA religion reporter Jerome Socolovsky has more.
Video

Video Fears of More Political Gridlock in 2015

2014 proved to be a difficult year politically for President Barack Obama and a very good year for the U.S. Republican Party. Republican gains in the November midterm elections gave them control of the Senate and House of Representatives for the next two years -- setting the stage for more confrontation and gridlock in the final two years of the Obama presidency. VOA National Correspondent Jim Malone has a preview from Washington.
Video

Video Sudan School Becomes Target of Aerial Attacks

The school dropout rate is at an all-time high in Sudan's South Kordofan state because many schools have been destroyed during the three-year civil war between the government and SPLA-N rebel forces. Adam Bailes visited Sudan's Nuba Mountains' region and reports many children are simply too scared to go to school
Video

Video VOA Reporter Tours Devastated Peshawar School

Islamist militants wearing military uniforms and strapped with explosives attacked a military run school Tuesday in the northwestern Pakistani city of Peshawar. At least 141 people were killed in the horrific attack, most of them young students. VOA reporter Ayaz Gul visited the devastated school and attended the funeral of the principal who courageously tried to save her students from the deadly attack.
Video

Video Nigerians Fleeing Boko Haram Languish in Camp Near Capital

In its five-year effort to impose Islamic law in northeastern Nigeria, the Boko Haram extremist group has killed thousands of people and forced hundreds of thousands to flee. Some of those who ran for their lives now live in squalor on the edges of the capital, Abuja. Chris Stein reports for VOA.
Video

Video Aceh Rebuilt Decade After Tsunami, But Scars Remain

On December 26, 2004 there was an earthquake in the Indian Ocean so powerful it caused the Earth’s axis to wobble a few centimeters. Onshore on the island of Sumatra, the resulting tsunami was devastating. A decade later, VOA Correspondent Steve Herman reports from Banda Aceh, Indonesia, where although there is little remaining evidence of the physical devastation, the psychological scars among survivors remain.

All About America

AppleAndroid