Pandemics

Simulations show H1N1 and COVID-19 spread through U.S. metro areas within weeks, with air travel a key driver

February 07, 2026 Iniulat ng AI Larawang ginawa ng AI Fact checked

Researchers at Columbia University’s Mailman School of Public Health used computer simulations to reconstruct how the 2009 H1N1 influenza pandemic and the 2020 COVID-19 pandemic expanded across U.S. metropolitan areas. The study, published in the Proceedings of the National Academy of Sciences, found that both viruses were already circulating widely in many cities within weeks, with air travel playing a larger role than daily commuting. The authors said broader wastewater surveillance, paired with infection-control measures, could help slow early spread in future outbreaks.