Santa Clara County, where the San Francisco 49ers train and play their NFL home games, has one of the highest covid vaccination rates in California. As of July 11, more than 76% of its vaccine-eligible residents were fully vaccinated, partly because the county and the 49ers franchise turned Levi’s Stadium into a mass inoculation site where more than 350,000 doses were administered over four months. The 49ers themselves, however, are not so enthusiastic about the shots. In June, head coach Kyle Shanahan said only 53 of the 91 athletes on the team roster — 58% — were fully vaccinated. The team h…