Epidemic Intelligence Service Program, Centers for Disease Control and Prevention, Atlanta, Georgia.
Respiratory Diseases Branch, Centers for Disease Control and Prevention, Atlanta, Georgia.
JAMA Intern Med. 2019 Apr 1;179(4):479-488. doi: 10.1001/jamainternmed.2018.7269.
Group B Streptococcus (GBS) is an important cause of invasive bacterial disease. Previous studies have shown a substantial and increasing burden of GBS infections among nonpregnant adults, particularly older adults and those with underlying medical conditions.
To update trends of invasive GBS disease among US adults using population-based surveillance data.
DESIGN, SETTING, AND PARTICIPANTS: In this population-based surveillance study, a case was defined as isolation of GBS from a sterile site between January 1, 2008, and December 31, 2016. Demographic and clinical data were abstracted from medical records. Rates were calculated using US Census data. Antimicrobial susceptibility testing and serotyping were performed on a subset of isolates. Case patients were residents of 1 of 10 catchment areas of the Active Bacterial Core surveillance (ABCs) network, representing approximately 11.5% of the US adult population. Patients were included in the study if they were nonpregnant, were 18 years or older, were residents of an ABCs catchment site, and had a positive GBS culture from a normally sterile body site.
Trends in GBS cases overall and by demographic characteristics (sex, age, and race), underlying clinical conditions of patients, and isolate characteristics are described.
The ABCs network detected 21 250 patients with invasive GBS among nonpregnant adults from 2008 through 2016. The GBS incidence in this population increased from 8.1 cases per 100 000 population in 2008 to 10.9 in 2016 (P = .002 for trend). There were 3146 cases reported in 2016 (59% male; median age, 64 years; age range, 18-103 years). The GBS incidence was higher among men than women and among blacks than whites and increased with age. Projected to the US population, an estimated 27 729 cases of invasive disease and 1541 deaths occurred in the United States in 2016. Ninety-five percent of cases in 2016 occurred in someone with at least 1 underlying condition, most commonly obesity (53.9%) and diabetes (53.4%). Resistance to clindamycin increased from 37.0% of isolates in 2011 to 43.2% in 2016 (P = .02). Serotypes Ia, Ib, II, III, and V accounted for 86.4% of isolates in 2016; serotype IV increased from 4.7% in 2008 to 11.3% in 2016 (P < .001 for trend).
The public health burden of invasive GBS disease among nonpregnant adults is substantial and continues to increase. Chronic diseases, such as obesity and diabetes, may contribute.
B 群链球菌（GBS）是一种重要的侵袭性细菌疾病的原因。先前的研究表明，非孕妇人群中 GBS 感染的负担很大且呈上升趋势，尤其是老年人和有潜在医疗条件的人群。
使用基于人群的监测数据更新美国成年人中侵袭性 GBS 疾病的趋势。
设计、地点和参与者：在这项基于人群的监测研究中，病例的定义是 2008 年 1 月 1 日至 2016 年 12 月 31 日期间从无菌部位分离出 GBS。从病历中提取人口统计学和临床数据。使用美国人口普查数据计算发病率。对一部分分离株进行抗生素敏感性试验和血清型鉴定。病例患者是主动细菌核心监测（ABCs）网络 10 个集水区之一的居民，代表美国成年人口的约 11.5%。如果患者是非孕妇、18 岁或以上、居住在 ABCs 集水区并且从正常无菌体部位分离出 GBS 阳性，则将其纳入研究。
描述了总体和按人口统计学特征（性别、年龄和种族）、患者潜在临床状况以及分离株特征的 GBS 病例趋势。
ABCs 网络在 2008 年至 2016 年间从非孕妇中检测到 21250 例侵袭性 GBS。该人群中的 GBS 发病率从 2008 年的每 10 万人 8.1 例上升到 2016 年的 10.9 例（趋势 P=0.002）。2016 年报告了 3146 例（59%为男性；中位年龄 64 岁；年龄范围 18-103 岁）。GBS 的发病率在男性中高于女性，在黑人中高于白人，且随年龄增长而增加。预计 2016 年美国有 27729 例侵袭性疾病和 1541 例死亡。2016 年 95%的病例发生在至少有一种潜在疾病的人身上，最常见的是肥胖症（53.9%）和糖尿病（53.4%）。克林霉素耐药率从 2011 年的 37.0%上升到 2016 年的 43.2%（P=0.02）。2016 年血清型 Ia、Ib、II、III 和 V 占分离株的 86.4%；血清型 IV 从 2008 年的 4.7%增加到 2016 年的 11.3%（趋势 P<0.001）。
非孕妇侵袭性 GBS 疾病的公共卫生负担很大且仍在增加。肥胖症和糖尿病等慢性疾病可能是导致这一问题的原因。
