Group B streptococcal disease in infants in the first year of life: a nationwide surveillance study in Japan, 2011-2015.

PURPOSE: This study aimed to describe the epidemiology of childhood group B streptococcus (GBS) disease including late late-onset disease (LLOD) and to clinically characterize recurrent cases and twin-sibling cases in Japan. METHODS: We collected information on infants (<1 year of age) with invasive GBS disease and institutional information about births and transfers through a nationwide questionnaire between 2011 and 2015. RESULTS: We identified 133 infants with early-onset disease (EOD), 274 late-onset disease (LOD), and 38 LLOD from 149 institutes. The case fatality rate (CFR) of EOD, LOD, and LLOD was 4.5, 4.4, and 0%, respectively. CFR in EOD was significantly (P < 0.001) associated with preterm birth, but not that in LOD and LLOD. Twenty-nine percent of infants with meningitis (49/169) had neurologic sequelae. We showed clinical details of 12 recurrent cases that accounted for 2.8% of the total patients, and 4 sets of both twins affected; 4 of 12 recurrent cases and 3 of 4 twin-sibling sets were also associated with preterm birth. Based on the livebirth number of 581,488, the instituted-based incidence of EOD, LOD, and LLOD was estimated as 0.09 (95% CI 0.06-0.11), 0.12 (95% CI 0.11-0.14), and 0.01 (95% CI 0.01-0.02) per 1000 livebirths, respectively. CONCLUSIONS: CFR of EOD and LOD in Japan is comparable with that in high-income European countries or the United States, and their incidence is much lower. Our findings also describe the clinical details of LLOD, recurrent infections, and infections in twin siblings. This study is the largest among Asian childhood GBS studies ever reported.

Early-onset and late-onset group B streptococcal disease in Japan: a nationwide surveillance study, 2004-2010.

OBJECTIVES: To clarify the incidence and prognosis of early-onset (EOD) and late-onset (LOD) GBS disease in Japan. To evaluate the influence of national guidelines issued in 2008 on the epidemiology of GBS disease. METHODS: Retrospective nationwide questionnaire surveillance on culture-confirmed GBS infections between 2004 and 2010. RESULTS: Eighty-eight EOD and 162 LOD cases were reported from 152 participating hospitals. The case fatality of EOD was 13.6% and of LOD was 8.0%. Premature birth <37 weeks (p<0.001) and low birth weight <2500 g (p<0.001) were significantly associated with EOD mortality. A high rate of neurological sequelae was noted in meningitis in EOD (8/24) and LOD (29/85) cases. Based on a live-birth number of 438359 and inborn case numbers of 36 EOD and 42 LOD, the incidence of EOD and LOD were estimated to be 0.08 (95% confidence interval (CI) 0.06-0.11)/1000 and 0.10 (95% CI 0.07-0.12)/1000 live-births, respectively. Before (2004-2008) and after (2009-2010) the issue of guidelines, the mortality of EOD (from 14.8% to 11.8%) and LOD (from 9.8% to 2.5%) improved, but the incidence was unchanged. CONCLUSIONS: The incidence of EOD and LOD is apparently low in Japan, but the mortality and morbidity rates remain substantial. The issue of national guidelines did not affect the incidence.

Trend of neonatal group B streptococcal infection during the last 15 years.

BACKGROUND: The survey was designed to determine the trend of group B streptococcal (GBS) infection during the last 15 years, as well as update the reality of this disease. METHODS: Questionnaires were administered every 5 years towards neonatal intensive care unit-equipped hospitals. The first survey was made from 1983 to 1987, the second one from 1988 to 1992 and the third one from 1993 to 1997. The 15-year questionnaire survey included a total of 831 patients. The changes in number of patients, the ages at onset, the diagnosis, the serotypes of causative agents, the presence or absence of complicated delivery and the prognosis were analyzed. RESULTS: It seems that the increasing trend of the number of patients has stopped in the period from 1993 to 1997 (third survey). The most common causative subtype was type III GBS, regardless of early onset type or late onset type. As to perinatal abnormality, approximately 40% of the early onset cases were free from risk factors. Concerning the prognosis, 22.6% of early onset cases and 38.7% of late onset cases died or had sequelae. CONCLUSIONS: The number of GBS-infected cases has stopped increasing, but it is still necessary to carry out screenings of pregnant women for the purpose of decreasing the onset of the disease.