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.


    Steve Baragona

    Steve Baragona is an award-winning multimedia journalist covering science, environment and health.

    He spent eight years in molecular biology and infectious disease research before deciding that writing about science was more fun than doing it. He graduated from the University of North Carolina at Chapel Hill with a master’s degree in journalism in 2002.

    You May Like

    New EU Asylum Rules Could Boost Rightists

    New regulations will seek to correct EU failures in dealing with migrant crisis, most notably inability to get member states to absorb a total of 160,000 refugees

    More Political Turmoil Likely in Iraq as Iran Waits in the Wings

    Analysts warn that Tehran, even though it may not be engineering the Sadrist protests in Baghdad, is seeking to leverage its influence on its neighbor

    Goodbye Ketchup, Hello Sriracha!

    How immigrants are triggering a great transformation in American cuisine

    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.
    Tensions Rising Ahead of South China Sea Rulingi
    X
    May 03, 2016 5:16 PM
    As the Philippines awaits an international arbitration ruling on a challenge to China's claims to nearly all of the South China Sea, it is already becoming clear that regardless of which way the decision goes, the dispute is intensifying. VOA’s Bill Ide has more from Beijing.
    Video

    Video Tensions Rising Ahead of South China Sea Ruling

    As the Philippines awaits an international arbitration ruling on a challenge to China's claims to nearly all of the South China Sea, it is already becoming clear that regardless of which way the decision goes, the dispute is intensifying. VOA’s Bill Ide has more from Beijing.
    Video

    Video Painting Captures President Lincoln Assassination Aftermath

    A newly restored painting captures the moments following President Abraham Lincoln’s assassination in 1865. It was recently unveiled at Ford’s Theatre in Washington, where America’s 16th president was shot. It is the only known painting by an eyewitness that captures the horror of that fateful night. VOA’s Julie Taboh tells us more about the painting and what it took to restore it to its original condition.
    Video

    Video Elephant Summit Results in $5M in Pledges, Presidential Support

    Attended and supported by three African presidents, a three-day anti-poaching summit has concluded in Kenya, resulting in $5 million in pledges and a united message to the world that elephants are worth more alive than dead. The summit culminated at the Nairobi National Park with the largest ivory burn in history. VOA’s Jill Craig attended the summit and has this report about the outcomes.
    Video

    Video Displaced By War, Syrian Artist Finds Inspiration Abroad

    Saudi-born Syrian painter Mohammad Zaza is among the millions who fled their home for an uncertain future after Syria's civil war broke out. Since fleeing Syria, Zaza has lived in Lebanon, Egypt, Jordan and now Turkey where his latest exhibition, “Earth is Blue like an Orange,” opened in Istanbul. He spoke with VOA about how being displaced by the Syrian civil war has affected the country's artists.
    Video

    Video Ethiopia’s Drought Takes Toll on Children

    Ethiopia is dealing with its worst drought in decades, thanks to El Nino weather patterns. An estimated 10 million people urgently need food aid. Six million of them are children, whose development may be compromised without sufficient help, Marthe van der Wolf reports for VOA from the Metahara district.
    Video

    Video Little Havana - a Slice of Cuban Culture in Florida

    Hispanic culture permeates everything in Miami’s Little Havana area: elderly men playing dominoes as they discuss politics, cigar rollers deep at work, or Cuban exiles talking with presidential candidates at a Cuban coffee window. With the recent rapprochement between Cuba and United States, one can only expect stronger ties between South Florida and Cuba.
    Video

    Video California Republicans Weigh Presidential Choices Amid Protests

    Republican presidential candidates have been wooing local party leaders in California, a state that could be decisive in selecting the party's nominee for U.S. president. VOA's Mike O’Sullivan reports delegates to the California party convention have been evaluating choices, while front-runner Donald Trump drew hundreds of raucous protesters Friday.
    Video

    Video Kurdish Football Team Helps War-Torn City Cope

    With the conflict still raging across much of Turkey’s predominantly Kurdish southeast, between the rebel PKK and the Turkish state, many Kurds are trying to escape the turmoil by focusing on the success of their football team Amedspor in Diyarbakir. The club is increasingly becoming a symbol for Kurds, not only in Diyarbakir but beyond. Dorian Jones reports from southeast Turkey.
    Video

    Video ‘The Lights of Africa’ - Through the Eyes of 54 Artists

    An exhibition bringing together the work of 54 African artists, one from each country, is touring the continent after debuting at COP21 in Paris. Called "Lumières d'Afrique," the show centers on access to electricity and, more figuratively, ideas that enlighten. Emilie Iob reports from Abidjan, the exhibition's first stop.
    Video

    Video Florida’s Weeki Wachee ‘Mermaids’ Make a Splash

    Since 1947, ‘mermaids’ have fascinated tourists at central Florida’s Weeki Wachee Springs State Park with their fluid movements and synchronized ballet. Performing underwater has its challenges, including cold temperatures and a steady current, as VOA’s Lin Yang and Joseph Mok report.
    Video

    Video Somali, African Union Forces Face Resurgent Al-Shabab

    The Islamic State terror group claimed its first attack in Somalia earlier this week, though the claim has not been verified by forces on the ground. Meanwhile, al-Shabab militants have stepped up their attacks as Somalia prepares for elections later this year. Henry Ridgwell reports there are growing frustrations among Somalia’s Western backers over the country’s slow progress in forming its own armed forces to establish security after 25 years of chaos.
    Video

    Video Nigerians Feel Bite of Buhari Economic Policy

    Despite the global drop in the price of oil, Nigerian President Muhammadu Buhari has refused to allow the country's currency to devalue, leading to a shortage of foreign exchange. Chris Stein reports from Lagos businessmen and consumers are feeling the impact as the country deals with a severe fuel shortage.

    Special Report

    Adrift The Invisible African Diaspora