Incidence of invasive infections with Group B streptococcus in adults in Norway 1996-2019: a nationwide registry-based case-control study.

Purpose: Group B streptococcus (GBS) colonizes the gastrointestinal and vaginal mucosa in healthy adults, but has also become an increasing cause of invasive infection. The aims of this study were to describe the incidence and factors associated with the occurrence of invasive GBS disease in adults in Norway.

Methods: We performed a nationwide retrospective case-control study of invasive GBS infections during 1996-2019, with two control groups; invasive Group A streptococcal disease (GAS) to control for changes in surveillance and diagnostics, and a second representing the general population.

The Streptococcus agalactiae R3 surface protein is encoded by sar5.

Streptococcus agalactiae (group B streptococcus; GBS) is an important human pathogen causing pneumonia, sepsis and meningitis in neonates, as well as infections in pregnant women, immunocompromised individuals, and the elderly. For the future control of GBS-inflicted disease, GBS surface exposed proteins are particularly relevant as they may act as antigens for vaccine development and/or as serosubtype markers in epidemiological settings. Even so, the genes encoding some of the surface proteins established as serosubtype markers by antibody-based methods, like the R3 surface protein, are still unknown.

Molecular characteristics of Streptococcus agalactiae strains deficient in alpha-like protein encoding genes.

Streptococcus agalactiae (group B streptococci, GBS) are important human and animal pathogens, which can be subdivided based on different capsular polysaccharides and surface-anchored alpha-like proteins (Alps), as well as other proteins. Nearly all GBS strains possess an Alp (Alp GBS), although Alp-negative GBS (non-Alp GBS) do occur. In this study, 10 (1.

Survey of immunological features of the alpha-like proteins of Streptococcus agalactiae.

Nearly all Streptococcus agalactiae (group B streptococcus [GBS]) strains express a protein which belongs to the so-called alpha-like proteins (Alps), of which Cα, Alp1, Alp2, Alp3, Rib, and Alp4 are known to occur in GBS. The Alps are chimeras which form mosaic structures on the GBS surface. Both N- and C-terminal stretches of the Alps possess immunogenic sites of dissimilar immunological specificity.

Comparison of PCR and serotyping of Group B Streptococcus in pregnant women: the Oslo GBS-study.

Streptococcus agalactiae (GBS) is a leading cause of invasive neonatal infection. Serotyping of GBS is important in following epidemiological trends and vaccine development. Capsular serotyping of GBS by latex agglutination has been the predominant typing method, but more recently capsular genotyping has been introduced as an alternative method.

Novel aspects of the Z and R3 antigens of Streptococcus agalactiae revealed by immunological testing.

Group B streptococci (GBS) are important human and bovine pathogens which can be classified by a variety of phenotype- and gene-based techniques. The capsular polysaccharide and strain-variable, surface-anchored proteins are particularly important phenotypic markers. In an earlier study, a previously unrecognized protein antigen called Z was described.

Identification of surface proteins of group B streptococci: serotyping versus genotyping.

We compared serotyping to genotyping of group B streptococcal (GBS) surface proteins in 147 Australasian isolates. Results were concordant for the two methods in 73.8% of 122 isolates, discordant for three and partially discordant for 29 isolates.

Immunological markers of the R4 protein of Streptococcus agalactiae.

This study focuses on immunological markers of R4, an important Streptococcus group B (GBS) protein. The results obtained by using rabbit antisera and purified proteins for antigens in enzyme-linked immunosorbent assay-based experiments provided evidence that R4 possesses two antigenic determinants. One of the determinants is shared with the alpha-like protein 3 (Alp3) of GBS, was named R4/Alp3 common, and was expressed by GBS, which possessed the Alp3-encoding gene alp3 or the R4-encoding gene rib.

Antigenic determinants of alpha-like proteins of Streptococcus agalactiae.

The majority of group B streptococcus (GBS) isolates express one or more of a family of surface-anchored proteins that vary by strain and that form ladder-like patterns on Western blotting due to large repeat units. These proteins, which are important as GBS serotype markers and as inducers of protective antibodies, include the alpha C (Calpha) and R4 proteins and the recently described alpha-like protein 2 (Alp2), encoded by alp2, and Alp3, encoded by alp3. In this study, we examined antigenic determinants possessed by Alp2 and Alp3 by testing of antibodies raised in rabbits, mainly by using enzyme-linked immunosorbent assays (ELISA) and an ELISA absorption test.