Trending Vacuna Covid 19 Usa / A covid‑19 vaccine is a vaccine intended to provide acquired immunity against severe acute respiratory syndrome coronavirus 2 (sars‑cov‑2), the virus causing coronavirus disease 2019. Vaccines approved for use and in clinical trials. Vacuna Covid 19 Usa - Food and drug administration issued the first emergency use authorization (eua) for a vaccine for the prevention of coronavirus.