In a statement on Monday, the UK Medicines and Healthcare products Regulatory Agency (MHRA) said it had given the green light to Moderna's combination "bivalent" vaccine, which will be used as an adult booster shot and will be offered to people aged 50 and over starting in the fall. 英国药品和保健品管理局（MHRA）在当地时间8月15日（周一）的一份声明中表示，它已经为莫德纳公司的“二价”组合疫苗开了绿灯，该疫苗将被用作成人加强针，并将从今年秋季开始提供给50岁及以上人群。

请问，and over这个连词加介词，在这里是什么用法啊？