Prevention of early onset group B streptococcal disease by universal antenatal culture-based screening in all public hospitals in Hong Kong.
OBJECTIVE
To determine the prevalence of maternal colonization with group B streptococcus (GBS), and early onset GBS disease (EOGBSD) after implementation of universal screening.


METHODS
This was a three-year retrospective cohort study on universal antenatal rectovaginal culture-based screening and intrapartum antimicrobial prophylaxis (IAP) to colonized women in the public sector in Hong Kong. Routinely collected data including maternal colonization and EOGBSD were retrieved.


RESULTS
Of 113,989 GBS screening performed, 21.8% were positive. The colonization rate was higher in the public hospitals (higher risk) than in the Maternal and Child Health Centers (lower risk) (23.7% vs 18.1%, p < .001), while their false negative rates were not greater than expected. Majority of eligible women opted for screening, and colonized women received IAP. There were 29 cases of EOGBSD with clinical signs and a positive blood or cerebrospinal fluid culture. Compared to clinical risk-based screening, EOGBSD incidence decreased after universal screening (1 vs 0.24 per 1000 births, p < .001). Although EOGBSD occurred at a higher rate in preterm than term infants, 86.7% occurred in the latter, and were associated with a false negative screening result (41.3%), lack of screening (20.7%) or unavailability of a colonization result at labour (13.8%).


CONCLUSIONS
Maternal GBS colonization rate was higher than previously reported, and varied with different risk populations. EOGBSD reduced after universal screening.
a Department of Obstetrics and Gynaecology , Queen Elizabeth Hospital , Hong Kong SAR , China.
Teresa W L
TWL
Ma
b Department of Obstetrics and Gynaecology , Kwong Wah Hospital , Hong Kong SAR , China.
Viola
V
Chan
c Department of Obstetrics and Gynaecology , Princess Margaret Hospital , Kowloon , Hong Kong SAR , China.
C H
CH
So
d Department of Obstetrics and Gynaecology , The Chinese University of Hong Kong , Hong Kong SAR , China.
Annie S Y
ASY
Hui
e Department of Obstetrics and Gynaecology , Pamela Youde Nethersole Eastern Hospital , Chai Wan, Hong Kong SAR , China.
C N
CN
Lee
f Department of Obstetrics and Gynaecology , Queen Mary Hospital , Hong Kong SAR , China.
Amelia P W
APW
Hui
g Department of Obstetrics and Gynaecology , Tuen Mun Hospital , Hong Kong SAR , China.
P L
PL
So
h Department of Obstetrics and Gynaecology , United Christian Hospital , Hong Kong SAR , China.
C W
CW
Kong
i Family Health Service, Department of Health , Hong Kong SAR , China.
Barbara
B
Fung
a Department of Obstetrics and Gynaecology , Queen Elizabeth Hospital , Hong Kong SAR , China.
K Y
KY
Leung
D000890:Anti-Infective Agents / Q000627:therapeutic use; D019072:Antibiotic Prophylaxis; D005260:Female; D006723:Hong Kong / Q000453:epidemiology; D006779:Hospitals, Public / Q000706:statistics & numerical data; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature; D018445:Infectious Disease Transmission, Vertical / Q000517:prevention & control*; D008137:Longitudinal Studies; D008403:Mass Screening / Q000379:methods / Q000706:statistics & numerical data*; D008430:Maternal-Child Health Centers / Q000706:statistics & numerical data; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000188:drug therapy / Q000453:epidemiology / Q000517:prevention & control; D015995:Prevalence; D012189:Retrospective Studies; D012307:Risk Factors; D013290:Streptococcal Infections / Q000188:drug therapy / Q000453:epidemiology* / Q000517:prevention & control
D000890:Anti-Infective Agents
Group B streptococcus; incidence; intrapartum antibiotic prophylaxis; prevention; risk factors; sepsis