June 8, 2012 -- Georgia officials who're just beginning their investigation of an E. Coli outbreak are racing against the clock to solve the mysterious food poisonings before the epidemic spreads, with the number of cases now at 11 across four southern states.
"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 said. "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 week 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," Dr. Takeisha Davis of the Louisiana Health Department said.
Alabama public health officials have linked two cases to the outbreak. And a 22-year-old Florida woman's illness has been traced to the same dangerous bacterium.
Aside from the E. coli strain, all the 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 lawyer and food safety advocate in Seattle.
Epidemiologists at CDC 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."
ABC News Medical Editor Dr. Richard Besser says that common links between those afflicted could hold the key.
"They're going to be looking for any link between these people -- what did they eat, where did they go, where did they shop?" Besser said Friday on "Good Morning America"."Until you know what caused this, you're going to be working around the clock. Until you solve this, lives are at stake."
For any E. coli outbreak at this time of year, suspicions immediately turn to undercooked ground beef. Safety experts advise consumers to cook ground beef to a temperature of 160 degrees. And, while they don't know if that's the case here, the CDC is reminding everyone to wash their hands after handling poultry and clean all fruits and vegetables. The period from April through September is what scientists call "high-prevalence season" for E. coli.
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.
Until this week, the government was not checking meat for the 0145 strain. But the U.S. Department of Agriculture for the first time began testing meat for six new strains of E. coli, including the strain causing this outbreak.
In an unrelated case, a 6-year-old boy in Millbury, Mass., died last week from kidney failure caused by E. coli. Massachusetts health officials said scientists have determined his illness was not caused by the same strain of E. coli as the clusters in the South. Officials in Tennessee said a recent E. coli case in that state was also unconnected.
ABC News' Brian Hartman contributed to this report