Measles surveillance in the United States tracks confirmed cases reported to the CDC. This market resolves based on whether cumulative measles cases in the U.S. will exceed 1900 by April 30, 2026. The current YES odds of 3 percent suggest traders view a major outbreak reaching that threshold as unlikely within the timeframe. Measles is a highly contagious respiratory disease with vaccination being the primary prevention strategy. Recent measles activity in the U.S. has remained relatively low compared to historical outbreaks, though importation of cases from other countries continues to occur. The resolution date of April 30, 2026, provides approximately two weeks from the market initiation date, making this a short-term prediction of outbreak trajectory. The market reflects current epidemiological conditions and vaccination rates across U.S. populations. For context, 1900 confirmed cases represents a significant increase from typical annual measles case counts seen in recent years. The stable odds around 3 percent indicate consistent market pricing based on available CDC surveillance data and current infection trends. This prediction market allows traders to express views on disease trajectory and public health outcomes without making recommendations regarding any particular position.