Group B streptococcal carriage among pregnant women and its implications


  • Venkataramana Kandi Department of Microbiology, Prathima Institute of Medical Sciences, Karimnagar, Telangana, India


Group B Streptococci, Pregnant women, Neonatal infections caused by group B Streptococci, Colonization of group B Streptococci


Group B streptococci are a group of gram positive cocci of Streptococcaceae family belonging to Lancefield group B, classified based on carbohydrate antigen. Streptococci are a group of gram positive cocci predominantly showing chain arrangement attributed to the type of cell division (linear). Among the various groups of streptococci group B Streptococci comprise normal micro biota of human genitourinary tract. Group B Streptococci are represented by Streptococcus agalactiae which are not only commensals but also recognized as a potential pathogen responsible for serious neonatal infections. Colonization in vagina prior to pregnancy may be considered as a risk factor for intra-partum and post-partum complications in pregnant women and neonates. Considering the fact that there are many serotypes of group B streptococci prevalent in different geographical regions and that there are no vaccine available, studies on epidemiology of colonization among risk groups and potential pathogenic nature of the colonizing bacteria assume significance. This paper enlivens the current knowledge of epidemiology of group B Streptococci.


Collee JG, Duguid JP, Marmion BP, Fraser AG. Beta haemolytic Streptococci. In: Collee JG, Duguid JP, Marmion BP, Fraser AG, eds. Mackie & McCartney, Practical Medical Microbiology. 13th ed. London: Churchill Livingstone; 2005: 323-325.

Edwards MS, Baker CJ. Streptococcus agalactiae (Group B Streptococcus). In: Mandell GL, Bennett JE, Dolin R, eds. Principles and practice of infectious diseases. 6th ed. Philadelphia: Elsevier, Churchill Livingstone; 2005: 2423-2434.

Chaudhry BY, Akhtar N, Balouch AH. Vaginal carriage rate of group B Streptococcus in pregnant women and its transmission to neonates. J Ayub Med Coll Abbottabad. 2010;22(4):167-70.

Cha Han, Wenjuan Wu, Aiping Fan, Yingmei Wang, Huiying Zhang, Zanjun Chu, et al. Diagnostic and therapeutic advancements for aerobic vaginitis. Arch Gynecol Obstet. 2015;291(2):251-7.

Mohsen Haghshenas Mojaveri, Yadollah Zahedpasha, Nesa Asnafi, Javad Farhadi, Ghamar Haddad. A survey on the prevalence of group B Streptococcus in pregnant women referred to the obstetrics and gynecology ward at Babol Ayatollah Rouhani hospital. Iran J Neonatol. 2014;5(1):23-7.

Turner C, Turner P, Po L, Maner N, Zoysa AD, Afshar B, et al. Group B streptococcal carriage, serotype distribution and antibiotic susceptibilities in pregnant women at the time of delivery in a refugee population on the Thai-Myanmar border. BMC Infect Dis. 2012;12:34.

Brzychczy-Włoch M, Gosiewski T, Bodaszewska-Lubas M, Adamski P, Heczko PB. Molecular characterization of capsular polysaccharides and surface protein genes in relation to genetic similarity of group B Streptococci isolated from Polish pregnant women. Epidemiol Infect. 2012 Feb;140(2):329-36.

Brimil N, Barthell E, Heindrichs U, Kuhn M, Lütticken R, Spellerberg B. Epidemiology of Streptococcus agalactiae colonization in Germany. Int J Med Microbiol. 2006;296(1):39-44.

Oviedo P, Pegels E, Laczeski M, Quiroga M, Vergara M. Phenotypic and genotypic characterization of Streptococcus agalactiae in pregnant women: first study in a province of Argentina. Braz J Microbiol. 2013;44(1):253-8.

Usein CR, Petrini A, Georgescu R, Grigore L, Străuţ M, Ungureanu V. Group B Streptococcus colonization of Romanian women: phenotypic traits of isolates from vaginal swabs. Roum Arch Microbiol Immunol. 2009;68(4):235-9.

Dutra VG, Alves VM, Olendzki AN, Dias CA, de Bastos AF, Santos GO. Streptococcus agalactiae in Brazil: serotype distribution, virulence determinants and antimicrobial susceptibility. BMC Infect Dis. 2014;14:323.

Shabayek SA, Abdalla SM, Abouzeid AM. Vaginal carriage and antibiotic susceptibility profile of group B Streptococcus during late pregnancy in Ismailia, Egypt. J Infect Public Health. 2009;2(2):86-90.

Shabayek S, Abdalla S. Macrolide- and tetracycline-resistance determinants of colonizing group B streptococcus in women in Egypt. J Med Microbiol. 2014;63(Pt 10):1324-7.

Shet A, Ferrieri P. Neonatal and maternal group B streptococcal infections: a comprehensive review. Indian J Med Res. 2004;120:141-50.

Dalal BS, Lahiri A, Parel CC. Carriage rate of group B streptococci in pregnant women and evaluation of different isolation media. J Indian Med Assoc. 1998;96:360-1,366.

Chaudhary U, Sabherwal U, Chugh TD. Prevalence of group B streptococci in obstetrical cases. Indian J Med Res. 1981;73:710-4.

Kulkarni AA, Pawar SG, Dharmadhikari CA, Kulkarni RD. Colonization of pregnant women and their newborn infants with group-B Streptococci. Indian J Med Microbiol. 2001;19:1-4.

Sharmila Vijayan, Noyal Mariya Joseph, Thirunavukkarasu Arun Babu, Latha Chaturvedula, Sujatha Sistla. Genital tract group B Streptococcal colonization in pregnant women: a South Indian perspective. J Infect Devel Countr. 2011 Feb;5(08):592-5.

Konikkara KP, Baliga S, Shenoy SM, Bharati B. Comparison of various culture methods for isolation of Group B Streptococcus from intrapartum vaginal colonization. J Lab Physicians. 2013;5:42-5.

Schrag S, Gorwitz R, Fultz-Butts K, Schuchat A. Prevention of perinatal group B Streptococcal disease. Revised guidelines from CDC. MMWR Recomm Rep. 2002;51(RR-11):1-22.

Verani JR, McGee L, Schrag SJ. Prevention of perinatal group B Streptococcal disease--revised guidelines from CDC, 2010. MMWR Recomm Rep. 2010;59(RR-10):1-36.

Narava S, Rajaram G, Ramadevi A, Prakash GV, Mackenzie S. Prevention of perinatal group B Streptococcal infections: a review with an Indian perspective. Indian J Med Microbiol. 2014;32:6-12.






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