Influenza Humancovid 19

This early-stage study will look at a new mRNA vaccine that combines defenses against both seasonal flu and COVID-19 in terms of its safety and how it builds protection. Healthy adults aged 65 to 85 will receive different doses of this new vaccine, a standard flu vaccine, or COVID-19 vaccine. The study will assess any side effects or health issues, and additional blood samples will be collected at specific times to evaluate how well participants bodies build protection against the flu and COVID-19.