Published: October 05, 2007 10:23 am            

E. Coli source may be outside Floyd County

Investigation into 10 confirmed and 5 suspected infections shifts to nonfood causes

A “smoking gun” in the investigation of the Floyd County E. coli outbreak has not emerged, but the collected evidence continues to suggest that the source was outside Galena Elementary School.

“The investigation is really ruling out some things, which can lead to the possibility that this strain is out in the environment and people are becoming naturally exposed to it,” said Pam Pontones, director of surveillance and investigation for the Indiana State Department of Health.

Natural exposures to E. coli infection include contact with livestock, manure or people who have already been infected.

In a letter posted on the New Albany-Floyd County Consolidated School Corp. Web site Thursday, Dr. Tom Harris, Floyd County health officer, wrote that DNA test results have shown a link between the strain of the E. coli in the Galena cases with an isolated case reported outside the county in August.

State and county health officials would not identify the location of the isolated case.

“This finding suggests that outbreak strain may have been circulating in the community or the environment prior to the outbreak,” Harris wrote. “Some cases do not attend Galena Elementary School nor reside in Floyd County.”

Epidemiological investigations have a success rate of 80 to 90 percent, Harris added.

Additional cases have been reported in recent weeks in Harrison County and Nelson County, Ky., but it wasn’t clear Thursday whether either case involved a similar strain as the ones in the Galena outbreak.

Harrison County health officials reported last week that the person infected had recovered.

The Centers For Disease Control and Prevention in Atlanta has been assisting in the investigation by comparing DNA samples of the Galena cases with other cases of 0157 — considered the most dangerous of hundreds of bacterial E. coli infections — in the country.

The number of confirmed Galena cases remains at 10 with five others listed as probable, pending laboratory test results. All but three cases are students at the elementary school and one is an adult.

Harris wrote that seven of the confirmed cases were “primary” and three were “secondary,” meaning they were passed from children to siblings or parents. The five probable cases have come up E. coli 0157 negative in the cultures, Harris stated.

“There have been many negative cultures completed,” he wrote.

Symptoms of the E. coli infection, including bloody diarrhea, reportedly began in cases as early as Sept. 17, but the first case was not reported until Sept. 21.

School has remained open since the first cases were reported.

“There is no evidence of ongoing transmission of the disease at Galena,” Harris wrote.

Health officials earlier this week determined using questionnaires filled out by Galena parents that the source was likely not in the cafeteria of the school. Health officials have given the cafeteria a clean bill of health.

Pontones said additional interviews were conducted with parents on Thursday.

“We’ll be analyzing the follow-up interviews to see if we find anything new,” she said.

        

• Click to discuss this story with other readers on our forums.