Kline Madeleine C, Kissler Stephen M, Whittles Lilith K, Barnett Michael L, Grad Yonatan H
Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Boston, MA, USA.
Center for Communicable Disease Dynamics, Harvard T.H. Chan School of Public Health, Boston, MA, USA.
medRxiv. 2023 Nov 16:2023.11.16.23298647. doi: 10.1101/2023.11.16.23298647.
Group A (GAS) causes an estimated 5.2 million outpatient visits for pharyngitis annually in the United States (U.S.) with incidence peaking in winter, but the annual spatiotemporal pattern of GAS pharyngitis across the U.S. is poorly characterized.
We used outpatient claims data from individuals with private medical insurance between 2010-2018 to quantify GAS pharyngitis visit rates across U.S. census regions, subregions, and states. We evaluated seasonal and age-based patterns of geographic spread and the association between school start dates and the summertime upward inflection in GAS visits.
The South had the most visits per person (yearly average 39.11 visits per 1000 people, 95% CI: 36.21-42.01), and the West had the fewest (yearly average 17.63 visits per 1000 people, 95% CI: 16.76-18.49). Visits increased earliest in the South and in school-age children. Differences in visits between the South and other regions were most pronounced in the late summer through early winter. Visits peaked earliest in central southern states, in December to January, and latest on the coasts, in March. The onset of the rise in GAS pharyngitis visits correlated with, but preceded, average school start times.
The burden and timing of GAS pharyngitis varied across the continental U.S., with the South experiencing the highest overall rates and earliest onset and peak in outpatient visits. Understanding the drivers of these regional differences in GAS pharyngitis will help in identifying and targeting prevention measures.
在美国，A 组链球菌（GAS）每年导致约 520 万例咽炎门诊就诊，发病率在冬季达到峰值，但美国 GAS 咽炎的年度时空模式特征尚不明确。
我们使用了 2010 年至 2018 年期间有私人医疗保险的个人的门诊理赔数据，以量化美国人口普查区域、次区域和各州的 GAS 咽炎就诊率。我们评估了季节性和基于年龄的地理传播模式，以及开学日期与 GAS 就诊量夏季上升拐点之间的关联。
南方的人均就诊次数最多（每年平均每 1000 人中有 39.11 次就诊，95%置信区间：36.21 - 42.01），西部最少（每年平均每 1000 人中有 17.63 次就诊，95%置信区间：16.76 - 18.49）。南方和学龄儿童的就诊次数最早增加。南方与其他地区之间的就诊差异在夏末至初冬最为明显。就诊高峰最早出现在中南部各州，在 12 月至 1 月，最晚出现在沿海地区，在 3 月。GAS 咽炎就诊量上升的开始与平均开学时间相关，但早于平均开学时间。
在美国大陆，GAS 咽炎的负担和发病时间各不相同，南方的总体发病率最高，门诊就诊的发病和高峰时间最早。了解这些 GAS 咽炎区域差异的驱动因素将有助于确定和针对性地采取预防措施。
