COVID-19 testing, incidence, and positivity trends among school age children during the academic years 2020-2022 in the State of Qatar: special focus on using CDC indicators for community transmission to evaluate school attendance policies and public health response

卡塔尔2020-2022学年学龄儿童新冠病毒检测、发病率和阳性率趋势：重点关注如何利用美国疾病控制与预防中心（CDC）社区传播指标评估学校出勤政策和公共卫生应对措施