Updated

State health officials are tracking the spread of swine flu through electronic prescription records, developing what they believe is a model that could help doctors more easily identify and respond to an outbreak of the illness.

Rhode Island is believed to be the first state to use electronic pharmacy prescription data to track swine flu among its entire population, said Rob Cronin, a spokesman for Surescripts, which operates the country's largest electronic prescriptions network. The company says it believes the state is also the first to have all of its pharmacies set up to receive electronic prescriptions from doctors.

Surescripts is using information supplied by pharmacies to document how much Tamiflu and other antivirals are being dispensed to patients. The company is giving the data — categorized by zip codes of the pharmacies where the medicine is dispensed and the age group of the patient receiving it — to epidemiologists at the state health department.

"This is a harbinger of capacities and abilities to come," said Laura Adams, president and chief executive of the Rhode Island Quality Institute, which works to improve health care in the state. "This is very important for us in terms of being able to stop something sooner rather than later."

The tracking initiative is being formally announced Monday by Gov. Don Carcieri.

The data is intended to show which communities are experiencing outbreaks or are hardest hit. But it can also reveal cases in which the medicine may be inappropriately or overzealously prescribed if, for instance, large numbers of prescriptions are dispensed in places where no uptick in cases has been reported.

President Barack Obama has declared the swine flu outbreak a national emergency. Health authorities say more than 1,000 people in the United States have died from the strain known as H1N1, and 46 states have widespread flu activity.

Rhode Island health director David Gifford has reviewed electronic prescription data from recent months, and the company says it now plans to give the state weekly data.

"It's a new tool in the tool bag," Gifford said. "This isn't a larger hammer or a larger saw. This is like, 'I had a hammer and saw and now I have a screwdriver.'"

There have been some other efforts beyond pharmacy prescriptions to track swine flu. Health agencies in places including New York City have used high-tech tools called syndromic surveillance systems — seen as especially useful after the Sept. 11 terrorist attacks to monitor for bioterrorism — to collect data from hospital emergency rooms.

New York City health authorities have also in recent years tracked over-the-counter pharmacy sales to detect outbreaks of flulike or gastrointestinal illnesses.

And after Hurricane Katrina in 2005, doctors were able to tap into a specially created Web site to access prescription histories for displaced Gulf Coast residents on whom they had no medical information.

But Cronin said he knew of no other statewide effort to track swine flu through electronic pharmacy prescriptions. The fact that all of Rhode Island's pharmacies are connected to an electronic prescribing network made it a natural place for Surescripts to roll out the initiative, which could be expanded to other states if successful here.

"If you have 100 percent of pharmacies, this system is going to be much, much more valuable to you than if you have 60 (percent)," Cronin said.

Surescripts receives swine flu data from 80 percent of Rhode Island's pharmacies but expects to boost that to 100 percent as soon as possible, Cronin said.

Andrew Pekosz, an associate professor of microbiology and immunology at the Johns Hopkins Bloomberg School of Public Health, said it makes sense to give states another vehicle for monitoring the illness, but cautioned that there could be inherent gaps in the data.

Assuming, for instance, that doctors are following federal guidelines and being conservative in their distribution of Tamiflu, the data could potentially underreport the actual number of people sick with flu, Pekosz said. Also, the numbers alone may not reflect how long the person took the medication or whether the patient it was prescribed for is ill or merely lives in a house with someone who has flu.

"You'll know that a physician felt strong enough that that person had influenza to give them a prescription," Pekosz said. "One doesn't know if that person then followed through in taking it appropriately and those kinds of things."