Flu Season Predictions

Jeffrey Shaman, an environmental health scientist at Columbia University, hopes that he and his colleagues will someday change the nightly news. “The way you get pollution reports and pollen counts on the local weather report, you could also have a flu forecast on there,” said Dr. Shaman.

Each year, the flu season arrives like clockwork. But once it strikes, it can unfold in surprising ways. In 2012, for example, it arrived in November, four weeks ahead of the typical flu season. Some years it can be especially brutal, and in others, very mild. Infection rates may start climbing in some parts of the United States when they are already falling in others.

Scientists like Dr. Shaman are reducing this uncertainty with computer models that make predictions about flu seasons in the United States. Last year, Dr. Shaman and his colleagues carried out their first flu forecasts in real time. They are now making predictions about the current outbreak, and this week they set up a website where you can see their predictions for yourself.

Their interest is greater than curiosity. Hospitals and public health workers could someday use flu forecasts to prepare their vaccine supplies and hospital beds. The advanced warning would be useful not only for the regular seasonal flu, but also for so-called pandemics, when a new strain sweeps across the country and causes higher rates of disease and death.

“In the event of a pandemic, this could become a more important issue,” said Matthew S. Biggerstaff, an epidemiologist at the Centers for Disease Control and Prevention in Atlanta. “We could understand how much lead time we had before a pandemic might peak, and it could help us get resources to the places that are going to need them.”

The spread of the flu is difficult to predict because it depends on many interconnected factors — how fast the virus replicates in people, for example, how well their immune systems wipe it out, and how easily the virus travels from one person to another. Despite decades of research on the flu, scientists are still deciphering some of the most important factors. Dr. Shaman and his colleagues, for example, have found that the drier the air is, the easier it is for viruses to spread from person to person.

Scientists are now using that understanding to make forecasts. To build computer models for predicting the flu, Dr. Shaman and his colleagues have gotten inspiration from meteorologists, whose embrace of mathematical tools has greatly improved their forecasting ability. “They really have the same problems for predicting the weather that we have for predicting influenza,” Dr. Shaman said.

To continue reading this article visit http://www.nytimes.com/2014/01/16/science/this-weeks-forecast-what-flu-season-may-look-like.html?_r=0