Cancer cells that have broken away from a primary tumor may reactivate when infected with the flu or COVID-19, according to a new study published in Nature. Researchers tested this hypothesis on mice with disseminated cancer cells and exposed them to SARS-CoV-2, the virus that causes COVID-19, or influenza viruses. The results showed that both infections triggered inflammation that awakened dormant cells located in the lungs.
The study builds on previous research that found COVID-19 increased patients’ risk of dying from cancer by 50%. However, it’s unclear how vaccination affects this risk. Further research is needed to determine if other factors, such as viruses or other sources, are required for cancer cells to grow and become life-threatening. The current study suggests that reactivation may be a temporary response to the infection.
The findings were made by a team of researchers led by James DeGregori and Julio Aguirre-Ghiso at the University of Colorado Cancer Center and Montefiore Einstein Comprehensive Cancer Center’s dormancy institute, respectively. While more research is needed, this study represents an important step forward in understanding the relationship between respiratory viruses and cancer reactivation.
Source: https://eu.usatoday.com/story/life/health-wellness/2025/07/30/flu-covid-sleeping-cancer-cells/85418692007