A pivotal study in Nature reveals that common respiratory viruses such as SARS-CoV-2 and influenza can awaken dormant metastatic breast cancer cells in the lung microenvironment. Experiments in mice demonstrate viral-induced inflammatory pathways facilitate cancer cell activation and metastasis, with human data supporting increased mortality and disease in cancer survivors post-infection. Findings underscore the complex interplay between infectious diseases and cancer recurrence, highlighting new considerations for patient management and preventative strategies.