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Last Updated

13 Jan 2003

Source: Boston Globe, October 3, 2002.

US plans a system to detect bioattack

By Stephen Smith, Globe Staff

The US Centers for Disease Control yesterday announced plans for a national early warning system against bioterror attack, using a system pioneered at Harvard that will look for signs of an anthrax, smallpox, or other disease outbreak in the aches, pains, and sniffles of 20 million patients.

The CDC is committing $1.2 million to a trial of the computerized surveillance network, which will review thousands of diagnoses daily for unusual patterns, such as a sudden increase in reports of flu-like symptoms that could signal an anthrax attack.

Early detection is pivotal. If smallpox and anthrax infections are caught in their first stages, patients can be treated much more effectively. In the case of smallpox, the spread can be contained.

''A system like this may give public health officials a three-day lead time. And that lead time may result in the saving of a great number of lives,'' said Dr. James Nordin, a clinical investigator at HealthPartners Research Foundation in Minnesota, which is participating in the experiment.

In addition, the system could provide early warnings of less sinister disease outbreaks, such as the flu or food poisoning. The lack of such surveillance in Milwaukee in 1993 resulted in hundreds of thousands of people getting sick from a water-borne illness before authorities recognized its scope.

The national system, expected to be operating within a year, will mirror a network begun in Boston nearly a year ago, in the midst of the anthrax scare.

Dr. Richard Platt, a Harvard infectious disease epidemiologist, led the team that created that surveillance network, which had not been scheduled to start until August 2002. But in the days following the Sept. 11 attacks, the decision was made to bring it on line as quickly as possible.

The anthrax attacks that began in early October of last year, ultimately killing five people, underscored the need for a national system for tracking bioterrorism. Since the attacks, public health officials have been even more concerned about smallpox because, unlike anthrax, it can be spread from person to person.

Since last fall, 14 Harvard Vanguard treatment centers have reported data every day on 250,000 patients. So far, the system has detected no suspicious patterns in the Boston area.

Now, Platt presides over the national coalition of researchers designing a system capable of tracking medical trends in all 50 states.

''It may be possible to get an earlier signal of a bioterrorism event by looking at the pattern of symptoms like cough than you could get by waiting until the first clearly recognizable bioterrorism infections appear,'' Platt said.

In many cases, the symptoms the surveillance network will track seem surprisingly routine - things like upper and lower respiratory infections and small rashes accompanied by fever. But that's exactly the point: to look for small signs of big problems.

The system will take information from health plans, clinics, and a company that runs a telephone hotline staffed by registered nurses who answer patient calls. It represents an unusual banding together of disparate, frequently competing, arms of the US health care system.

But Platt knew that if doctors and other medical staff were asked to complete more paperwork in a field already drowning in documents, a tracking system was doomed to fail. Instead, the surveillance system prepares computers to review standard medical reports. Those reports are automatically measured against years of medical history for unusual patterns.

That way, the system will be able to determine, for instance, if the number of respiratory cases on a Thursday in early October varies dramatically from Thursdays in past Octobers. Then, the computer hunts for geographic clusters of cases.

''There's a big difference,'' Platt said, ''between having five people who are sick in a ZIP code with 100 people than a ZIP code with 10,000 people.''

When worrisome patterns emerge, public health authorities will be alerted so that they can open an investigation to ascertain whether a cluster of coughing is attributable to a winter virus or whether it's evidence of a rogue bacterial agent circulating.

Smallpox is a leading example of how early intervention can translate into effective treatment and a limited spread of disease.

Researchers know that if patients are inoculated soon after being exposed to smallpox, that shot can stop symptoms from manifesting. And centuries of experience with the disease show that it's vital to contain it geographically - something best done before thousands of people are exposed.

If the national trial proves successful, infectious disease specialists predict that the network will be expanded to cover an even broader spectrum of patients.

While the fear of bioterrorism is prompting creation of the national system, its greatest value may prove to have nothing to do with terrorists.

The need for such a network was demonstrated in 1993 when Milwaukee's water supply was fouled by a microbe called cryptosporidium due to runoff from a cattle lot. More than 400,000 people became ill and 100 died, in part because it took days for disease trackers to realize an epidemic was felling thousands.

''These investments in the surveillance system are clearly going to have multiple purposes in making the public health system stronger,'' said Dr. Steven L. Solomon, acting director of the division of health care quality promotion at CDC.