Some four in 10 COVID-19 patients in a hospital in California during late December 2021 and most of January were fully vaccinated, according to a new study. The percentage of fully patients in an academic hospital in California climbed from 25 percent in the summer of 2021 to 40 percent after the Omicron virus variant became dominant in the United States, researchers said in the study, published by the Centers for Disease Control and Prevention’s (CDC) quasi-journal. The number of unvaccinated patients in the hospital, which was not identified dropped from 71 percent when the Delta virus variant was dominant to 56 percent following Omicron’s emergence, according to the study, which analyzed electronic health records. Fully vaccinated refers to patients who received two doses of the Moderna or Pfizer-BioNTech COVID-19 vaccines, or those who got the single-shot Johnson & Johnson jab, at least 14 days before getting a positive COVID-19 …