Norovirus Spreading Among Republican Convention Staff by Sheila Kaplan @FortuneMagazine July 20, 2016, 3:12 PM EDT E-mail Tweet Facebook Linkedin Share icons This piece originally appeared on STATnews.com. Public health authorities said Wednesday that testing has confirmed that about a dozen Republican convention staffers in Ohio had been struck by norovirus. Peter Schade, the Erie County health commissioner, said he met Wednesday morning with members of the group, who were part of the advance team for California’s delegation to the convention. Schade said investigators do not yet know how the staffers contracted the severe gastrointestinal bug, but they believe the chain of transmission started in California. Republican National Convention Replay E-mail Tweet Facebook Linkedin Share icons Fullscreen gallery Republican U.S. presidential nominee Donald Trump reacts to balloons, confetti and electronic fireworks as he stands with his son Barron (L) at the conclusion of the final session of the Republican National Convention in Cleveland, Ohio, U.S. July 21, 2016. Jonathan Ernst — Reuters Balloons fall as Trump and vice presidential nominee Governor Mike Pence stand with their families onstage at the end of the final session. Aaron Bernstein — Reuters Balloons drop Trump’s speech. Carlo Allegri — Reuters Trump and Pence stand on stage after Trump’s speech. Rick Wilking — Reuters Medea Benjamin of Code Pink is carried out after disrupting the speech of Trump. Tom Williams — AP Trump delivers a speech during the evening session on the fourth day of the Republican National Convention John Moore — Getty Images Ivanka waves as she walks off stage after introduction her father. J. Scott Applewhite — AP Ivanka Trump delivers a speech during the evening session. Jeff J Mitchell — Getty Images Peter Thiel, co-founder of PayPal, delivers a speech during the evening session Win McNamee — Getty Images Sen. Cory Booker, D-N.J., makes his way through a crowd into the main entrance of the Quicken Loans Arena. Jabin Botsford — The Washington Post The Washington Post/Getty Images Police horses stand in a line in Cleveland Public Square. Monica Jorge — Sipa USA/AP A delegate wears an American flag themed flower on a hat. Andrew Harer — Bloomberg via Getty Images A pro-Trump supporter waves a flag among a crowd of counter protestors. Monica Jorge — Sipa USA/AP A man holds a sign aloft during an anti-Trump protest. Andrew Kelly — Reuters Singer Heavenly Joy performs during the start of the fourth day. Win McNamee — Getty Images A man with a security credential takes a selfie at the podium as Trump, flanked by campaign manager Paul Manafort and daughter Ivanka, checks the podium early Thursday afternoon in preparation for accepting the GOP nomination to be President. Bill Clark — AP Trump stands with Republican vice presidential candidate Mike Pence and acknowledge the crowd on the third day. Chip Somodevilla — Getty Images Eric Trump, son of Trump, addresses the third session of the Republican National Convention. Brian Snyder — Reuters People react to Sen. Ted Cruz, R-Tex., as Cruz addresses the delegate during the third day session. Matt Rourke — AP Cruz gives a thumbs up after speaking during the third night. Mike Segar — Reuters A police officer holds a confiscated American flag after arresting a protester. Victor J. Blue — Bloomberg via Getty Images A supporter of the Revolutionary Communist Party is arrested by police after assisting other members with burning a U.S. flag outside the gates. Adrees Latif — Reuters Cleveland police officers detain a protester. Lucas Jackson — Reuters Cleveland police officers clash with a group. Lucas Jackson — Reuters Law enforcement officers clash with protesters. John Minchillo — AP Law enforcement officers take a protester into custody. Patrick Semansky — AP A law enforcement officer clashs with protester who is holding a burning an American flag. John Minchillo — AP Boxing promotor Don King is seen on the convention floor. Aaron Josefczyk — Reuters Delegates bow their heads before the start of the third day of the Republican national Convention. Jim Watson —AFP/Getty Images Delegates celebrate on the floor of the Republican National Convention after the Speaker of the House Paul Ryan announces Trump’s official nomination on July 19, 2016 in Cleveland, Ohio. Photo by Jeff Swensen—Getty Images Television personality Omarosa is interviewed during the second day. Jonathan Ernst — Reuters Protesters clash with police. John Minchillo — AP Trump’s children Donald Trump, Jr., Ivanka Trump, and Eric Trump celebrate on the convention floor. Carolyn Kaster — AP Former Republican presidential candidate Ben Carson delivers a speech. Alex Wong — Getty Images Members of the Alaskan delegation react after Donald Trump secured the nomination. Jabin Botsford — The Washington Post/Getty Images Supporters of Republican U.S. presidential nominee Donald Trump attempt to obscure a protestor from the activist group Code Pink, who is holding an anti-racism and anti-hate banner, as she interrupts the proceedings. Mark Kauzlarich — Reuters Delegates cheer as a signboard shows the announcement of Republican U.S. presidential candidate Donald Trump’s name being placed into nomination. Brian Snyder — Reuters New Jersey Governor Chris Christie and his wife Mary Pat Christie react during Donald Trump, Jr’s speech. Toni L. Sandys — The Washington Post/Getty Images Donald Trump Jr. gestures to the crowd after delivering a speech. Joe Raedle — Getty Images Tiffany Trump, daughter of Republican presidential candidate Donald Trump, prepares for her speech at the Republican National Convention in Cleveland, Ohio on Tuesday, July 19, 2016. Carolyn Kaster — AP Senate Majority Leader Mitch McConnell (R-KY) uses the gavel as he checks out the stage before his scheduled speech this evening on the second day. Joe Raedle — Getty Images Protesters clash over the American flag in Public Square. Alex Brandon — AP Trump kisses his wife Melania after she concluded her remarks at the Republican National Convention in Cleveland, Ohio on Monday, July 18, 2016. Mario Anzuoni — Reuters Presumptive Republican presidential nominee Donald Trump, arrives to introduce his wife Melania Trump as she prepares to address delegates. Anthony Behar — Sipa USA/AP New Jersey Gov. Chris Christie is surrounded by photographers as he attends the evening session. Matt Rourke — AP People in the crowd try to block anti-war protestor Alli McCracken (C) of the “Code Pink” activist group. Carlo Allegri — Reuters A delegate yawns prior to the start of the evening portion. Brian Snyder — Reuters Former Mayor of New York City Rudy Giuliani addresses delegates. Anthony Behar — Sipa USA/AP Bob Dole attends the first day. Tasos Katopodis — WireImage/Getty Images Delegates sit as signs lay on the floor. John Taggart — Bloomberg via Getty Images Former Republican U.S. presidential candidate and former Texas Governor Rick Perry takes the stage to speak. Jim Young — Reuters Wisconsin Gov. Scott Walker takes a photo with a delegate. Joe Raedle — Getty Images Police on bicycles create a cordon around demonstrators from various groups, including “End Poverty NOW! March for Economic Justice,” as they march in protest. Adrees Latif — Reuters The anti-Trump movement appears all but defeated. But that doesn’t mean they’ll go quietly. John Locher — AP Willie Robertson, star of the television show “Duck Dynasty,” speaks at the convention. Brian Snyder — Reuters Demonstrators listen as the band Prophets of Rage performs during an End Poverty Now rally. John Minchillo — AP A Republican National Convention delegate screams as the Chair announces that the convention will not hold a roll-call vote on the Republican National Convention Rules Committee’s report and rules changes and rejects the efforts of anti-Trump forces to hold such a vote. Mark Kauzlarich — Reuters Members of the Texas delegation waive their hats on the floor. An estimated 50,000 people are expected in Cleveland, including hundreds of protesters and members of the media. Samuel Corum — Anadolu Agency/Getty Images Republican National Convention delegates yell and scream as the Republican National Committee Rules Committee announces that it will not hold a recorded vote on the Rules Committee’s Report and rejects the efforts of anti-Trump forces to hold a roll-call vote. Jonathan Ernst — Reuters A policewoman holds back a “Black Lives Matter” supporter as she shouts towards supporters of Donald Trump, who said they were members of “Bible Believers” during the Republican National Convention. Adrees Latif — Reuters Jake Byrd of California dances on the convention floor on the first day of the Republican National Convention on July 18, 2016 at the Quicken Loans Arena in Cleveland, Ohio. Joe Raedle — Getty Images A Trump/Pence poster appears over the convention floor. Dominick Reuter — AFP/Getty Images Former U.S. Senator from New Hampshire Gordon Humphrey, a leader in the “Never Trump” movement, holds a business card in front of his face as he arrives on the floor. Brian Snyder — Reuters A woman yells as she is taken into custody by police during the Republican National Convention. Shannon Stapleton — Reuters Bob Little from Warren Mich., salute as he observes a presentation. Matt Rourke — AP Dana Dougherty from Deltona, Fla., cheers as she holds a Donald Trump figure. Carolyn Kaster — AP Journalists talk with a man openly carrying a gun downtown. Jeff J Mitchell — Getty Images Sharon Day, Co-Chair of the Republican National Committee, speaks during the first day. Carolyn Kaster — AP Trump supporters Kay Kellogg Katz, left, and Gena Gore from Monroe, La., cheer. Matt Rourke — AP Delegates crowd the convention floor. John Moore — Getty Images Texas delegates to the Republican National Convention hold their hands over their hearts for the U.S. National Anthem. Mike Segar — Reuters Speaker of the House Rep. Paul Ryan, R-Wis., laughs during a breakfast with Pennsylvania delegates during the Republican National Convention in Westlake, Ohio. Evan Vucci — AP Corey Lewandowski arrives to the floor of Quicken Loans Arena. Matt Rourke — AP Demonstrators chant during an anti-Donald Trump rally in Cleveland. Jim Watson — AFP/Getty Images Reince Priebus, chairman of the Republican National Committee, bangs the gavel to officially the open the first day of the Republican National Convention. Win McNamee — Getty Images A delegate appears on the floor. Tom Williams — CQ-Roll Call,Inc./Getty Images A delegate wears campaign buttons in support of Donald Trump before the start of the Republican National Convention. Andrew Harrer — Bloomberg via Getty Images Two men dressed in suits stand as people gather downtown for the first day. Jeff J Mitchell — Getty Images Delegate George Engelbach, right, gestures to his hat while laughing with a fellow delegate. John Taggart — Bloomberg via Getty Images The Tennessee delegation section is seen before the opening. Andrew Caballero-Reynolds — AFP/Getty Images Booklets are placed on chairs as the Quicken Loans Arena is prepared for the arrival of delegates on the first day of the Republican National Convention in Cleveland, Ohio on the first day. Joe Raedle — Getty Images Senate Majority Leader Mitch McConnell speaks with Robert “Mike” Duncan, former chairman of the Republican National Committee, left, during a walk through inside the Quicken Loans Arena “The Q” ahead of the Republican National Convention. Andrew Harrer — Bloomberg via Getty Images Demonstrators march during the Shut Down Trump & the RNC protest. John Minchillo — AP A woman takes a selfie from the stage as preparations get underway on July 17th. Jeff Swensen — Getty Images A man holds up a sign against Presidential candidates Trump and Hillary Clinton outside the Quicken Loans Arena. Bloomberg Bloomberg via Getty Images A campaign bus from Herman Cain’s 2012 Republican candidacy is covered with signs for the comedian Samantha Bee amid preparations for the arrival of visitors and delegates. Dominick Reuter — AFP/Getty Images Women pose nude for photographer Spencer Tunick’s art installation “Everything She Says Means Everything” near the location of the Republican National Convention. Lucas Jackson — Reuters A protester carrying a peace flag walks in downtown Cleveland. Patrick Semansky — AP Anti-Trump organizations and Black Lives Matter protesters walk through downtown ahead of the Republican Convention. Douliery Olivier — Sipa US/AP Workers place a sign as they prepare at Quicken Loans Arena for the convention. Matt Rourke — AP A Cleveland Police officer directs traffic as protesters march in the street. Victor J. Blue — Bloomberg via Getty Images Talk show host Stephen Colbert performs on the floor of the Quicken Arena during a taping of his program. Colbert plans to do live, on-the-ground coverage of the convention. Carolyn Kaster — AP A protester dressed as Trump walks past restaurant patrons ahead of the convention. Many protesters are expected at the convention. John Taggart — Bloomberg via Getty Images U.S. House Speaker Paul Ryan (R-WI) participates in a rehearsal before the Republican National Convention. After initially withholding his endorsement of Trump, Ryan agreed to speak at the RNC. Aaron Bernstein — Reuters Police officers use bicycles to create cordons around a protest march by various groups, including “Black Lives Matter” and “Shut Down Trump and the RNC,” ahead of the convention. Adrees Latif — Reuters Preparations continue in the arena ahead of the RNC. Jonathan Ernst — Reuters More on Fortune Turkish President Reassures Country as Attempted Coup Falters How Great Photographers Do Food Porn These aerial views of New York City will take your breath away Comic Con + Cosplay = Magic ∨ Show Full Caption 1 of “It came with them,” Schade said. Health officials are now taking food histories from those who had fallen ill — and are staying at a resort hotel about an hour outside of Cleveland — to try to pinpoint the cause. For more on Republican National Convention, watch this video: “We’re asking, ‘What did you guys do? Did you do anything together before you came out?”’ Schade said. Noroviruses cause violent bursts of vomiting and diarrhea. It’s highly contagious, and those who contract it typically experience symptoms for only one to three days; most people recover without medical care. Some victims, however, especially young children or the elderly, require treatment for dehydration. The Centers for Disease Control and Prevention says that noroviruses are the leading cause of illness and outbreaks from contaminated food in the US. Jim Brulte, chairman of the California delegation, told STAT in an email Tuesday that the outbreak began when one of the staffers came down with a virus and infected her husband. Since it has been 36 hours since the last new case, Schade said, he is optimistic that the bug has been contained.