Gizachew et al. BMC Pediatrics (2018) 18:378 https://doi.org/10.1186/s12887-018-1350-1 RESEARCH ARTICLE Open Access Newborn colonization and antibiotic susceptibility patterns of Streptococcus agalactiae at the University of Gondar Referral Hospital, Northwest Ethiopia Mucheye Gizachew1*, Moges Tiruneh1, Feleke Moges1, Mulat Adefris2, Zemene Tigabu3 and Belay Tessema1 Abstract Background: Group B Streptococcus (GBS) that asymptomatically colonizing the recto-vaginal area of women is the most important cause of neonatal colonization. There is paucity of evidence about newborn colonization with GBS in Ethiopia. Thus, this study was aimed to determine the prevalence of newborn colonization with GBS, antibiotic susceptibility patterns of the isolates and associated risk factors at the University of Gondar Referral Hospital in Northwest Ethiopia Methods: A prospective cross sectional study was conducted from December 2016 to November 2017. A total of 1,155 swabs from nasal, ear and umbilical areas of the newborns were collected from the 385 newborns. Identifications of the isolates and antibiotic susceptibility testing were done by using conventional methods. Results: Sixty two (16.1%, 95% CI: 12.2% - 20%) of the newborns were colonized by GBS. Seven percent of the total specimens were positive for GBS. The antibiotics susceptibility rates of GBS (average of the three body sites tested) were 95.1%, 89.6%, 88.9%, 85.7%, 85.3%, 81.3%, 76.9%, 76.1%, 73.8%, and 34.4% to ampicillin, penicillin, ciprofloxacin, chloramphenicol, vancomycin, azitromycin, erythromycin, clindamycin, ceftriaxone, and tetracycline, respectively. A multilogistic regression analyses were shown that the newborns that were from mothers whose education status was below tertiary level, and newborns from mothers who were: being employed, being nullipara and multigravida were at risk for colonization with GBS. Conclusion: Prevalence of neonatal colonization with GBS was higher than it was reported in three decades ago in Ethiopia. Ciprofloxacin, chloramphenicol, vancomycin and azithromycin were identified as the drug of choice next to ampicillin and penicillin. Keywords: Antibiotic susceptibility pattern, Colonization, Group B Streptococcus, Newborns Background [1]. Women in the Amhara National Regional State have The 2016 Ethiopian Demographic and Health Survey the fertility rate of 4.2, and infant and maternal mortality (EDHS) indicates that the overall mortality rate of under rates of 76/1000 live births and 676/100,000, respectively five children is 67/1000 live births, with the infant mor- [2]. Asymptomatic Streptococcus agalactiae (Group B tality rate of 48% (29% neonatal and 19% post-neonatal) Streptococcus, GBS) recto-vaginal colonization of women deaths/1,000 live births. The estimate of child mortality is assumed to be one of the contributing factors. It is the is 20 deaths/1000 children surviving to 12 months of age most significant pathogen, although little is known about its epidemiology and risk in resource limited countries [3]. Since neonatal infections cause a significant proportion of * Correspondence: [email protected] deaths in the first week of life, more data are needed about 1Department of Medical Microbiology, School of Biomedical and Laboratory Sciences, College of Medicine and Health Sciences, University of Gondar, P. the burden of neonatal colonization [4]. O. Box 196, Gondar, Ethiopia Full list of author information is available at the end of the article © The Author(s). 2018 Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated. Gizachew et al. BMC Pediatrics (2018) 18:378 Page 2 of 11 Since 1960s, GBS has been identified as a major public Regional State Health Bureau report showed that the health problem that causes perinatal morbidity and mortal- Amhara region has a population of 20,018,988, of which, ity. It also became the most prevalent causes of fatal 49.92% were females, and 15.62% of the total population infections in newborns [5–7]. The researchers estimated was urban inhabitants. The hospital serves about five about 410,000 GBS cases and 147,000 stillbirths and infant million people. It has 450 to 600 delivery admission deaths are estimated to occur every year. Despite contain- services a month. No GBS screening and provision of ing 13% of the world's population, Africa had the highest intrapartum antibiotic prophylaxis for pregnant women burden with 54% cases and 65% of stillbirths and infant established yet in the hospital. deaths [8]. GBS causes sepsis, pneumonia, and meningitis in neonates; bacteraemia, amnionitis, endometritis, and Study Design and Period urinary tract infection in pregnant women [9–11]. The Glo- A prospective cross-sectional study design was conducted bal prevalence of GBS neonatal colonization rate ranged between December 2016 and November 2017. from 1.6% in Turkey [12] to 52.9% in Pakistan [13], and South Africa took the lion share among few African reports Population [14]. However, evidence on GBS colonization rate of new- Source population borns largely remains sparse in the African setting, particu- All newborns who were delivered at the University of larly in Ethiopia. Gondar Referral Hospital in Northwest Ethiopia were Furthermore, provision of empiric treatment brings up the source population. antibiotic resistance and stewardship issues [8]. Reports from different countries revealed the reduced suscepti- Study population bility to penicillin, and the increased rate of macrolide The study populations were those newborns delivered resistance GBS isolates for the last few decades [15]. A from pregnant women whose gestational age was ≥ 35 2005-2007 Surveillance in Argentina showed the pres- weeks. ence of GBS isolates resistance (in minimum inhibitory μ concentration; MIC range g /L) to ciprofloxacin (32-64 Inclusion and exclusion criteria μ μ μ g/L), levofloxacin (16-32 g/L), ofloxacin (32-64 g/L), Inclusion criteria μ and norfloxacin (32-64 g/L), and all were susceptible to Newborns whose mothers not on antibiotics during de- μ penicillin (0.06 g/L) (16). Of the 1160 GBS isolates in livery and those newborns who have been delivered vagi- Australia, 6.4% demonstrated erythromycin resistance nally at ≥35 gestational weeks of pregnancy, and infants and 4.2% to clindamycin [16]. Another study in USA re- ≤ 30 minutes were included in the study. vealed that all the neonatal GBS were susceptible to penicillin, vancomycin, chloramphenicol, and cefotaxime. Exclusion criteria Its resistance rates to erythromycin was 20.2%, and 6.9% Newborns whose mothers; did use vaginal cream, lubri- to clindamycin [17]. Another study in France revealed cants or traditional sterilizer (vinegar) in the last 10 days 38.2% erythromycin and 25.6% clindamycin resistance prior to giving birth; were in emergency room, severely neonatal GBS [18]. However, as is the case in several other ill, current vaginal bleeding, use of an intra-vaginal prod- African countries, neonatal GBS colonization in Ethiopia uct in the past 24hours (douche, antifungal products), has not been well documented. In addition, no preventive mentally unstable pregnant women; those who were in strategies for GBS infection have been yet formulated in multiple birth and refusal for study participation from the study area. Thus, this study was aimed to determine mothers or guardians were excluded. the prevalence of newborn colonization with GBS, its anti- biotic susceptibility profile, and associated risk factors in Sample size determination University of Gondar referral hospital, Northwest The sample size was calculated using the single popula- Ethiopia. tion proportion estimation formula by taking 5% as the prevalence of neonatal GBS colonization [19]. Methods 2 Â ð − Þ n ¼ z α=2 p 1 P Where; n= sample size, p = prevalence Study area d2 The study was conducted at the University of Gondar of neonatal colonization with GBS in Ethiopia (p = 5%), Referral Hospital, Northwest Ethiopia. The University of d= maximum allowable error (margin of error) = 0.05, Gondar Referral Hospital is one of the oldest hospitals Z = value of standard normal distribution (Z-statistic) located 737 km away from Addis Ababa, the Capital of at 95% confidence level (z=1.96) and it became 73 new- Ethiopia with the Latitude of 12o31`N,and Longitude borns; however, to increase the precision/validity of the 37o25`E.. The Central Statistical Agency of Ethiopia findings, the sample size was increased to 385 by taking population projection report and the Amhara National p = 50%. Gizachew et al. BMC Pediatrics (2018) 18:378 Page 3 of 11 Variables sub-cultured in 5% defibrinated sheep-blood agar and Dependent variable incubated for 24 hours at 37 °C in 5% CO2 atmosphere. Colonization of newborns with Group B Streptococcus All suspected colonies (with narrow hemplysis) were (GBS), Antibiotic susceptibility patterns of GBS. sub-cultured on nutrient agar and subjected to gram stain and catalase test. All gram positive cocci and cata- Independent variables lase negative isolates