Accuracy in reporting remains a problem, because it depends on the sophistication of electronic systems used by local and state health agencies to quickly gather data for the federal government.
In the past few years, electronic tools have begun to transform the reporting system -- reducing or eliminating the burden on doctors, nurses or medical laboratories to fill out reports on potential epidemics, according to Scott Danos, an independent consultant in Atlanta.
Damos, a former senior advisor at the CDC who retired after more than 30 years with the agency, said the basic challenge in tracking epidemics has been that patient diagnosis and treatment data comes in many forms to the local and state health agencies, which in turn must hand it off to the CDC and HHS. Those agencies have to analyze the data and then send back information to the states.
About four years ago, the CDC launched a national program called BioSense, which gave state health agencies an application that can transmit and receive epidemic data with federal agencies basic in near real-time. The data, which comes from larger hospitals, laboratories and other health data sources, is compiled by the CDC and offers states a big-picture view of where a potential epidemic may be spreading.
For example, if a number of people going to hospitals with flu-like symptoms -- or if there's a run on a particular type of medical test -- that data is reported through BioSense to the CDC from the state health agencies. The CDC then cross-references that information with data it receives from large national health care providers, pharmacies and other government agencies such as the U.S. Department of Veterans Affairs.
"They then overlay it in sophisticated ways in Atlanta along with views back to every state so they can go in and query it to see what's happening where they are," Damos said. But there is no precise data about individual patients and whether specific cases of Swine Flu have been confirmed. And out of the approximately 7,500 hospitals in the US, only several hundred are feeding into the CDC's BioSense health data network.