Vaginal & rectal carriage of Streptococcus agalactiae in the Czech Republic: incidence, serotypes distribution & susceptibility to antibiotics.

BACKGROUND & OBJECTIVES: Streptococcus agalactiae (group B streptococcus, GBS) is the predominant bacterial agent responsible for invasive perinatal infection. To obtain reliable data on vaginal and rectal carriage of S. agalactiae in pregnant women in Czech Republic, and to formulate a prevention programme of neonatal GBS disease for the Czech Republic, women at childbirth were screened for vaginal and anorectal carriage of GBS. The isolates were serotyped and tested for susceptibility to antimicrobials including those recommended for intrapartum prophylaxis. METHODS: A total of 586 women at childbirth were screened for GBS carriage in vaginal and anorectal regions using the non-enrichment and selective culture media. The isolates were serotyped by precipitation with antisera raised against various serotypes and antigenic extracts prepared according to Lancefield's modification. Mueller Hinton agar with 5 per cent defibrinated sheep blood was used for antimicrobial susceptibility testing. MIC values were evaluated according to the NCCLS criteria. RESULTS: Using selective media, GBS was detected in 172 (29.3%) of 586 women screened, vaginal and anorectal colonization was found in 21.7 and 24.4 per cent of them, respectively, concomitant vaginal and anorectal colonization was recorded in 16.5 per cent of the women studied. Serotypes III (33.2%), Ia (22.0%) and V (13.9%) prevailed among 172 isolates tested. All isolates were susceptible to penicillin, ampicillin and cefotaxime. The rates of GBS resistance to tetracycline, erythromycin and clindamycin were 83.9, 3.8 and 3.2 per cent, respectively. INTERPRETATION & CONCLUSION: GBS carriage in pregnant women in the Czech Republic is rather high as compared with that reported in literature. The most frequent serotypes III, Ia and V, identified in GBS-colonized pregnant women in the Czech Republic, were among those predominant in the USA and Western Europe. Our findings confirm uniform susceptibility of GBS isolates from pregnant women to penicillin and other beta-lactam antibiotics tested. Resistance to erythromycin remains low in the Czech Republic.

Active surveillance of early onset disease due to group B streptococci in newborns.

BACKGROUND & OBJECTIVES: Early onset disease (EOD) due to group B streptococci (GBS) poses a serious threat in many countries. In the Czech Republic neither summarized data on the EOD incidence are available nor a nationwide prevention program has been initiated. The present surveillance was initiated to establish the incidence of EOD due to GBS in newborns in the Czech Republic, distribution of GBS serotypes and GBS susceptibility to antimicrobials. METHODS: Both invasive and carrier GBS isolates from newborns and the data on the newborns' clinical status and maternal colonization and intrapartum prophylaxis were collected from 30 microbiological and clinical centres all over the Czech Republic within prospective active surveillance. HCl extracts of the GBS strains were precipitated with rabbit polysaccharide (I-VIII) and protein (c,R) antisera. RESULTS: Between January 2001 and September 2002, GBS isolates from 239 full-term and 46 preterm newborns were collected. Of the 285 GBS positive newborns, 105 had invasive EOD, 42 showed suspected EOD, and in 56 clinical diagnosis was not specified. Eighty two GBS isolates were obtained from healthy colonized infants. The isolates obtained from newborns with confirmed invasive EOD were mostly of serotype III (42%), followed by serotypes V a Ia (13% each). Types Ia (26%), III (22%) and II (20%) were most frequent among the isolates from colonized individuals. Protein antigens (c protein, R protein) either coupled with polysaccharide or alone were found in 70 per cent (30 and 40 %, respectively) of the study isolates. INTERPRETATION & CONCLUSION: The incidence of EOD due to GBS found in the Czech Republic 0.7-1.0 per 1000 live births was comparable with the rates reported in the countries where the prevention programme has been implemented nationwide. Serotypes III, V and Ia prevailing among the isolates from Czech newborns with EOD belonged to those most frequently identified in the USA and Western European countries.