DeKalb and Fulton counties report relatively few cases of serious, drug-resistant staph infections to the state health department despite their large populations, data for the past three years show.

Just 43 residents of DeKalb County (population 737,000) have been reported hospitalized with severe infections from a staph strain called MRSA. In Fulton County (population 992,000), the number is 76.

Jason Getz/AJC (ENLARGE)

Microbiologist Greg Fosheim examines genetic fingerprints of MRSA bacteria at the Centers for Disease Control and Prevention.

Jason Getz/AJC (ENLARGE)

At the CDC, Valerie Schoonover examines samples of Staph.

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By comparison, 146 cases have been reported involving residents of Cobb County (population 692,000). Even Floyd County (population 96,000) has reported 123 cases, according to a state database of reports filed from January 2005 through February.

State health officials said there is no reason to believe there's more MRSA in Cobb County than in DeKalb and Fulton combined. The differences most likely reflect variations in how well doctors are reporting cases, they said.

MRSA, which stands for methicillin-resistant Staphylococcus aureus, is believed to infect thousands of Georgians every year. But most cases are never reported to the state. Often that's because the infections involve common treatable boils and pimples. Only severe or deadly infections that were contracted outside of hospitals are supposed to be reported to the Georgia Division of Public Health.

MRSA has circulated within hospitals since the 1960s. It began when staph bacteria mutated in response to the use of antibiotics and since has been spread between patients on the hands of health care workers, according to the Centers for Disease Control and Prevention.

But in recent years, MRSA infections have increasingly occurred in the community involving people outside of health care settings.

Georgia doesn't require reporting of hospital-associated MRSA cases. But in late 2004, the state health department began requiring that doctors, hospitals and labs report within seven days of diagnosis cases of community-associated MRSA that result in "severe illness or death."

"We wanted to better characterize infections in Georgia in a broad sense," said Cherie Drenzek, chief of the state's protection and safety epidemiology unit. "We wanted to know: What is the magnitude? Are we seeing these severe outcomes? Are there any seasonal patterns?"

Georgia is one of only a handful of states to collect this data.

More than 1,700 cases of severe MRSA infections have been reported since January 2005; 62 involve deaths.

Among the reported cases, few were turned over to state officials within the required seven days. Weeks or months may pass after a person is sickened and before a report is filed, the data show.

The low number of reports —43— from DeKalb County stands out given its population. And it would have been even smaller if a CDC-funded research group doing medical file reviews as part of a comprehensive regional MRSA study hadn't uncovered more than a dozen previously unreported cases last November. Many of the cases the researchers found involved people sickened six months earlier, records show.

"I'm hesitant to focus on numbers," said Heidi Davidson, coordinator for the office of infectious diseases at the DeKalb County Board of Health. "This is a new surveillance system in terms of having MRSA reportable."

Health care providers, she said, are still feeling out what's reportable and what's not.

No special review of the MRSA reporting process is planned in DeKalb.

In Fulton, health department officials said they'll be taking a closer look at reporting. As in DeKalb, data show CDC-funded researchers uncovered several Fulton County MRSA cases that had gone unreported for months.

On average, MRSA cases from Fulton County were reported to the state 69 days after the person became ill.

"That number of days, I have consternation, but no explanation," said Bob Finton, director of epidemiology at the Fulton County Department of Health and Wellness.

State officials say the system isn't perfect, but it's been useful in helping them identify larger trends statewide.

"We wanted a system that would allow us to find out about terrible outcomes," said Dr. Katie Arnold, an infectious diseases epidemiologist at the Georgia Division of Public Health.

Unlike other reportable diseases that require immediate action by health officials to prevent outbreaks, delays in reporting community-associated MRSA are less important because the information is being used to identify larger trends, state officials said.

Last fall, a research group that includes scientists at the CDC and Emory University estimated that there were 94,360 serious and invasive MRSA infections nationwide in 2005. Nearly 19,000 of these people are estimated to have died, the study said.

The study's estimates didn't include less severe MRSA infections, such as pimples or boils, which are far more common.

About 85 percent of all invasive MRSA infections, which include bloodstream and organ infections, involved people who had recently received treatment at a health care facility. Only about 15 percent of invasive MRSA infections were estimated to have occurred in the community, according to the research published in the Journal of the American Medical Association.

Fueled by media publicity about MRSA last fall, several schools across the country —including some in Cobb County and Atlanta— closed briefly to sanitize their buildings because of reports of individual students who had been diagnosed with MRSA skin infections or boils.

The panic and emphasis on cleaning surfaces was misplaced, experts said, because the bacteria are spread through skin-to-skin contact or sharing intimate items, such as razors and towels.

For more information about MRSA, go to: health.state.ga.us/mrsa/ or www.cdc.gov/ncidod/dhqp/ar_mrsa_ca.html

To read the AJC's report on community-associated MRSA in Georgia, which was published Sunday, see www.ajc.com/health.

Researcher Sharon Gaus contributed to this report.