The Gallup-Healthways Well-Being Index daily tracking surveys asked U.S. adults, "Were you sick with allergies yesterday?" every day since September 2008, with about 30,000 interviews per month.
On average, more U.S. adults reported being sick with allergies on a given day in every month so far in 2012 than Gallup found in the same months of previous years.
The March rate of 19.6 percent was significantly higher than the rate in March of previous years, such as 16.5 percent in 2011.
More Americans reported being sick with allergies on any given day so far in April, at 22.8 percent, than in April 2011, at 20.8 percent, and April 2010, at 21.8 percent, or during the peak of allergy season last year, when 22.1 percent reported allergies in May.
What remains unclear is whether this U.S. allergy spring season will peak in April, as it did in 2010, or in May, as it did in 2009 and 2011, Gallup officials said. On any given day throughout the year, at least 10 percent of U.S. adults reported being sick with allergies.
For the March results, the margin of error was 0.6 percentage points, while for April 1 to 15, the margin of error was 0.9 percentage points.