(WASHINGTON) -- As the number of E. coli cases climbs to 11 across four southern states, Georgia officials who say they're just beginning their investigation are now racing against the clock to solve these mysterious food poisonings before the epidemic spreads further.
"We know that these cases are all linked, and that would suggest that there was a common source somewhere along the way," J. Patrick O'Neal of the Georgia Department of Health told ABC News. "We just don't know where."
The death of an infant in New Orleans last week has been linked to at least 10 other cases of E. coli illness in Georgia, Florida, Louisiana and Alabama. The largest cluster of five sickened people, ranging in age from 18 to 52, is centered in Atlanta, home to the Centers for Disease Control and Prevention.
Maelan Elizabeth Graffagnini was 21 months old when she died last Thursday at a hospital in New Orleans. Two others in the New Orleans area were also recently stricken by the same strain of E. coli, known as 0145.
"The death of a young child is always difficult, and it serves as a reminder of how serious E. coli is," said Dr. Takeisha Davis of the Louisiana Health Department.
Alabama public health officials have linked two cases to this outbreak. And in Florida, a 22-year-old woman's illness has been traced to the same dangerous bacterium.
Aside from the E. coli strain, all these cases have in common is that officials still have no idea what caused the illnesses.
"They are racing against the clock, they want to figure out what the product is, and get it out of the market before it sickens or kills anyone else," said Bill Marler, a food safety attorney.
Epidemiologists at the CDC's headquarters are poring over data sent in from the states in search of a common factor that could pinpoint a cause.
"The likely exposure is a food source," Louisiana Department of Health spokesman Tom Gasparoli said. "But this has yet to be confirmed. Often, the contact source is not found."
E. coli are a common bacteria and not every strain is dangerous. But some, like those that carry the 0145 genetic fingerprint that is behind this outbreak, produce a deadly toxin known as shiga. This poison can cause violent reactions, including severe kidney damage and death.
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