Issues related to mandatory COVID-19 vaccination continue to roil employment settings in many parts of the nation, as deadlines approach and courts weigh in on requirements.In other developments, a large multistate study based on data from the Centers for Disease Control and Prevention (CDC) and several health systems found that mRNA vaccines were less effective at preventing hospitalization in immunocompromised people when compared with their peers who don't have underlying health conditions.Mandate issues come to a headA deadline for COVID-19 vaccination for New York City's municipal workers arrived yesterday, and nearly 9,000 were placed on unpaid leave for not complying, according to the New York Times.