Researchers from the University of Massachusetts at Amherst and Johns Hopkins have developed a new method to determine the onset of influenza season, which will help health care workers deliver more accurate treatments and prevent more flu cases.
The researchers created an open-source algorithm -- Above Local Elevated Respiratory Illness Threshold (ALERT) -- to statistically detect a rise in influenza transmission in a specific region.
They used data from 2001 to 2011 gathered from two hospitals in Baltimore and Denver to create the algorithm, then tested the algorithm during the 2011-12 and 2013-14 flu seasons at the two hospitals.
The findings of their study appear in the current edition of Clinical Infectious Diseases.
Health professionals take many issues under consideration before declaring the beginning of flu season. Many extra precautions, such as gloves, masks and gowns, require additional funding, while other safety measures, including dressing in protective gear and sanitizing procedures, require extra time. Alternatively, too few precautions increase the chances of spreading the flu.
"All the extra precautions cost time and money, so you don't want to declare flu season too early,” Nicholas Reich, biostatistician at the University of Massachusetts Amherst who led the project, said. “For hospitals, there is a strong incentive to define a really clear period as flu season. It does not start the moment you see the first case in the fall. If you begin the full response too early, you set yourself up for a long slog and too much effort will be spent on too few cases. You want to be as effective and efficient as possible in your preparations and response."
The ALERT technique does not require additional data collection from local health professionals. Instead, the algorithm measures the data that health care providers already gather, such as the weekly counts of influenza cases confirmed in the laboratory.
"The more years of data you have, the better," Reich said. "We have applied it in places with only three to five years of data and it's still been a useful tool, but the more years you have the more accurate it will be."