Forecasting the Flu Hot Zone

Summer in New York may be uncomfortably steamy, but we’re months from worrying about catching the flu from an errant sneeze on the subway. In subtropical cities like Hong Kong, however, influenza outbreaks come and go year-round.

For the last two years, researchers Jeffrey Shaman and Wan Yang at Columbia University’s Mailman School of Public Health have published reliable flu forecasts for cities across the United States, allowing individuals and officials to prepare weeks ahead of the seasonal peak. Now, for the first time, Shaman and Yang have shown that they can do the same in a subtropical region. Results are published in the journal PLOS Computational Biology. (Read the press release.)

Working with collaborators at the University of Hong Kong, the Mailman researchers modified their computer model, which uses techniques from weather forecasting, to accommodate subtropical flu patterns and make accurate predictions for overall flu as well as individual strains, including influenza A (H3N2), influenza B, and both seasonal and the 2009 pandemic outbreaks of influenza A (H1N1). The researchers expect to publish real-time predictions for Hong Kong in advance of the next influenza season (forecasts will appear the Columbia Prediction of Infectious Disease website, cpid.iri.columbia.edu).

The study focuses on Hong Kong, a densely populated city of 7 million highly connected with mainland China and the rest of the world. “What’s very interesting is that flu is very often associated with South Asia where Hong Kong is located,” says Shaman, associate professor of Environmental Health Sciences, in a new video. “A lot of the new flu strains seem to emerge from there. Certainly pandemic flu strains emerge there. Having a foothold [in Hong Kong] and being able to make predictions in that area of the world is going to be very valuable on the larger stage—on the global stage.”