As of November 2021, the CDC has announced that foreign travelers will be permitted to travel to the U.S. with proof of having been vaccinated with one of the FDA- or WHO-approved coronavirus vaccines. The FDA has authorized three COVID-19 vaccines for emergency use during the pandemic: Moderna, Johnson & Johnson and Pfizer-BioNTech. The WHO has granted approval for those three as well as the Oxford-AstraZeneca/Covishield, Sinopharm and Sinovac vaccines.
Before you leave for San Diego, please double-check the guidelines for international travelers to the United States.