J Korean Med Sci.  2018 Apr;33(16):e127. 10.3346/jkms.2018.33.e127.

Seroprevalence of Opsonophagocytic Antibodies against Serotype Ia, Ib, II, III, and V Group B Streptococcus among Korean Population

• Lee JH
• Kim HW
• Kim KH

• KMID: 2408666
• DOI: http://doi.org/10.3346/jkms.2018.33.e127

Abstract

BACKGROUND
Invasive Streptococcus agalactiae (group B streptococcus, GBS) infection most commonly occurs in infants; however, cases of GBS infection in adults, particularly in the elderly with significant underlying diseases, are being increasingly reported. We analyzed the serotype specific opsonophagocytic antibodies (the major mechanism of protection against GBS) in infants, adults, and the elderly.
METHODS
The opsonization indices (OIs) of antibodies against serotype Ia, Ib, II, III, and V GBS were studied in 89 infants, 35 adults (age, 30-50 years), and 62 elderly individuals (age, 65-85 years) according to the University of Alabama at Birmingham GBS opsonophagocytic killing assay protocol (www.vaccine.uab.edu).
RESULTS
In infants, adults, and elderly groups respectively, geometric mean of OI against GBS serotype Ia were 3, 7, and 32; against GBS serotype Ib were 7, 242, and 252; against serotype II were 93, 363, and 676; against serotype III were 8, 212, and 609; and against serotype V were 4, 639, and 610. The seropositive rate (% of subjects with OI ≥ 4) increased significantly in older age group for all five serotypes.
CONCLUSION
During infancy, only a limited proportion of infants have functional immunity against serotype Ia, Ib, II, III, and V GBS. Furthermore, a lack of opsonic activities against GBS observed in some adults and the elderly might predispose such individuals to the risk of invasive GBS infection. Epidemiological monitoring and development of suitable vaccine for these populations are needed.

Keyword

Streptococcus agalactiae; Serotype; Antibodies; Prevalence; Population

MeSH Terms

Adult
Aged
Alabama
Antibodies*
Epidemiological Monitoring
Homicide
Humans
Infant
Prevalence
Seroepidemiologic Studies*
Serogroup*
Streptococcus agalactiae
Streptococcus*
Antibodies