Cools Piet, Jespers Vicky, Hardy Liselotte, Crucitti Tania, Delany-Moretlwe Sinead, Mwaura Mary, Ndayisaba Gilles F, van de Wijgert Janneke H H M, Vaneechoutte Mario
Laboratory Bacteriology Research, Department of Microbiology, Immunology, and Clinical Chemistry, Faculty of Medicine and Health Sciences, Ghent University, Ghent, Belgium.
Unit of Epidemiology and Control of HIV/STD, Department of Public Health, Institute of Tropical Medicine, Antwerp, Belgium.
PLoS One. 2016 Jan 26;11(1):e0148052. doi: 10.1371/journal.pone.0148052. eCollection 2016.
One million neonates die each year in low- and middle-income countries because of neonatal sepsis; group B Streptococcus (GBS) and Escherichia coli are the leading causes. In sub-Saharan Africa, epidemiological data on vaginal GBS and E. coli carriage, a prerequisite for GBS and E. coli neonatal sepsis, respectively, are scarce but necessary to design and implement prevention strategies. Therefore, we assessed vaginal GBS and E. coli carriage rates and risk factors and the GBS serotype distribution in three sub-Saharan countries.
A total of 430 women from Kenya, Rwanda and South Africa were studied cross-sectionally. Vaginal carriage of GBS and E. coli, and GBS serotype were assessed using molecular techniques. Risk factors for carriage were identified using multivariable logistic regression analysis.
Vaginal carriage rates in reference groups from Kenya and South Africa were 20.2% (95% CI, 13.7-28.7%) and 23.1% (95% CI, 16.2-31.9%), respectively for GBS; and 25.0% (95% CI, 17.8-33.9%) and 27.1% (95% CI, 19.6-36.2%), respectively for E. coli. GBS serotypes Ia (36.8%), V (26.3%) and III (14.0%) were most prevalent. Factors independently associated with GBS and E. coli carriage were Candida albicans, an intermediate vaginal microbiome, bacterial vaginosis, recent vaginal intercourse, vaginal washing, cervical ectopy and working as a sex worker. GBS and E. coli carriage were positively associated.
Reduced vaginal GBS carriage rates might be accomplished by advocating behavioral changes such as abstinence from sexual intercourse and by avoidance of vaginal washing during late pregnancy. It might be advisable to explore the inclusion of vaginal carriage of C. albicans, GBS, E. coli and of the presence of cervical ectopy in a risk- and/or screening-based administration of antibiotic prophylaxis. Current phase II GBS vaccines (a trivalent vaccine targeting serotypes Ia, Ib, and III, and a conjugate vaccine targeting serotype III) would not protect the majority of women against carriage in our study population.
在低收入和中等收入国家，每年有100万新生儿死于新生儿败血症；B族链球菌（GBS）和大肠杆菌是主要病因。在撒哈拉以南非洲，关于阴道GBS和大肠杆菌携带情况的流行病学数据稀缺，而这分别是GBS和大肠杆菌所致新生儿败血症的前提条件，但对于设计和实施预防策略而言却必不可少。因此，我们评估了撒哈拉以南三个国家的阴道GBS和大肠杆菌携带率、危险因素以及GBS血清型分布情况。
对来自肯尼亚、卢旺达和南非的430名女性进行了横断面研究。采用分子技术评估GBS和大肠杆菌的阴道携带情况以及GBS血清型。使用多变量逻辑回归分析确定携带的危险因素。
肯尼亚和南非参照组的阴道GBS携带率分别为20.2%（95%置信区间，13.7 - 28.7%）和23.1%（95%置信区间，16.2 - 31.9%）；大肠杆菌携带率分别为25.0%（95%置信区间，17.8 - 33.9%）和27.1%（95%置信区间，19.6 - 36.2%）。GBS血清型Ia（36.8%）、V（26.3%）和III（14.0%）最为常见。与GBS和大肠杆菌携带独立相关的因素有白色念珠菌、中等阴道微生物群、细菌性阴道病、近期阴道性交、阴道冲洗、宫颈异位以及从事性工作者。GBS和大肠杆菌携带呈正相关。
倡导诸如避免性交等行为改变以及在妊娠晚期避免阴道冲洗，可能会降低阴道GBS携带率。在基于风险和/或筛查的抗生素预防给药中，探讨纳入白色念珠菌、GBS、大肠杆菌的阴道携带情况以及宫颈异位的存在情况可能是可取的。在我们的研究人群中，目前的II期GBS疫苗（一种针对血清型Ia、Ib和III的三价疫苗以及一种针对血清型III的结合疫苗）无法保护大多数女性免受携带感染。
