A room full of infected patients failed to spread the flu to others in the room with them, in new study. 🤯 In a study that sounds like the beginning of a pandemic thriller, researchers from the University of Maryland placed flu-infected college students in a confined hotel room with healthy volunteers. Despite hours of shared air and close contact without masks, not a single healthy participant contracted the virus. The results, published in PLOS Pathogens, challenge long-held assumptions about how easily the flu spreads in indoor settings. While the infected donors had high viral loads in their nasal passages, the lack of transmission suggests that simple proximity may not be the primary danger factor we once believed. The key to this unexpected outcome lies in three factors: airflow, coughing, and participant age. Because the infected students coughed infrequently, significantly less virus was aerosolized into the environment. Meanwhile, constant air circulation from heaters and dehumidifiers diluted the remaining viral particles, preventing them from reaching infectious concentrations. These findings emphasize that improving indoor air quality through ventilation and portable purifiers may be just as vital as physical distancing. For those in high-risk environments, the study reinforces that while air quality is a powerful shield, an N95 mask remains the gold standard defense when coughing is present. Source: University of Maryland. (2026). Evaluating modes of influenza transmission (EMIT-2): Insights from lack of transmission in a controlled transmission trial with naturally infected donors. PLOS Pathogens.