Todd Doan, a music teacher, was diagnosed with liver cancer caused by chronic hepatitis B virus (H.B.V.) infection. Despite being preventable and treatable, H.B.V. affects 254 million globally, causing 1.1 million deaths annually. Doan's case highlights the stealth nature of H.B.V., which can remain undetected for decades, leading to late-stage diagnosis and limited treatment options. The article emphasizes the need for increased public health efforts, awareness, and funding to combat H.B.V., which disproportionately affects Asian, Pacific Islander, and African populations.