Serotypes of group B streptococci in western Sweden and comparison with serotypes in two previous studies starting from 1988

Abstract

BackgroundGroup B Streptococci (GBS) are the most common neonatal pathogens and infect immunocompromised and elderly individuals. The species has 10 different serotypes. Serotypes have been studied in the south-west area of Sweden in 1988–1997 and 1998–2001. The aim of this study was to study serotypes in the same area from 2004 to 2009.MethodsInvasive GBS isolates were collected prospectively from 2004 to 2009 in two counties in western Sweden with a population of 1.8 million, and were serotyped by latex agglutination. Clinical data were obtained from hospital records. During the study period 410 invasive GBS isolates from 398 patients were collected (multiple episodes ≥1 month apart). Clinical data were not available for two patients who are excluded. Four isolates were from stillborn neonates, 88 were from live born neonates and infants, and 318 from adults.ResultsSerotype III was the most common serotype (48 %) in neonates and infants followed by serotypes Ia (18 %) and V (16 %). In adults serotype V (39 %) dominated followed by serotypes III (20 %) and Ib (14 %). There was a significant increase of serotype V in comparison with the first study (1988–1997) but there were no significant changes in the serotype distribution between the present study and the second study (1998–2001). There were a few cases of serotype VI-IX, both in children and adults, not seen in the previous studies. Serotype V was more common among patients with arthritis than with any other manifestation.ConclusionsChanges in GBS serotypes occur over time in the same region, which must be considered when GBS vaccines are formulated.

Perinatal Streptococcus agalactiae Epidemiology and Surveillance Targets

“…As mentioned above, a study in southern Ghana observed CPS IX as having the second highest prevalence, behind CPS VII (47). A Swedish study assessed changes in serotype distribution over time for invasive disease (neonatal and adult populations) and suggested that circulating serotypes remained stable from 1990 onwards; however, the study noted an increase in CPS VII to IX (55). Additionally, a case study in Japan described an incidence of ultra-late-onset sepsis caused by CPS IX, and this demonstrates its capacity to play a role in disease (56).…”

Prevalence and capsular type distribution of Streptococcus agalactiae isolated from pregnant women in Namibia and South Africa

“…Studies in Malawi [19], Finland [20], Sweden [21], England [22], United States [23], Zimbabwe [18], Gambia [24], Egypt [25] and in Brazil [26] have shown variations in serotype distribution around the world. This study therefore sought to determine the prevalence of GBS and capsular type distribution of isolates colonising pregnant women in Namibia and South Africa.…”

Increasing Resistance and Changes in Distribution of Serotypes of Streptococcus agalactiae in Poland

“…The obtained results are consistent with the available literature data [ 17 , 20 , 34 , 38 ]. The occurrence of individual serotypes (Ia, Ib, and II–IX) is different, depending on the geographical region of the world and ethnicity assessed; it also changes for a given region over the time [ 39 , 40 , 41 , 42 ]. Among 353 strains isolated from pregnant women from the Małopolska province in Poland, the serotypes III (35%) dominated among the tested strains, followed by Ia (20%), V (17%), II (15%), Ib (8%), and IV (5%) [ 43 ].…”