Trend of isolation and serotypes of group B streptococci in Korea.

Group B streptococci (GBS) neonatal infection, a prevalent disease in western countries, is considered rare in Korea. GBS neonatal infection is known to be often due to serotype III organisms, but the serotypes in Korea have not been reported. In this study, GBS were frequently isolated from specimens of genitalia, urine and various pus. Among the 186 isolates 14 (7.5%) were from neonates, two with concomitant bacteremia and meningitis and one with pneumonia. Frequently isolated GBS serotypes were Ib (9.2%), Ib/c (26.6%) and III/R (23.9%). Change of frequently isolated serotypes during the study was noted, but JM9 which became increasingly isolated in Japan was not found. It is concluded that less prevalence of severe neonatal GBS infection in Korea is not due to the absence of serotype III, but possibly due to low genital carriage rate of GBS by pregnant women.

A study of haemolytic streptococci isolated from outpatients in dermatological clinics.

A total of 44 patients suspected of streptococcal infections were studied in outpatient clinics in Tokyo during the one year from December 1988 to December 1989. Employing bacteriological culturing and serodiagnosis, the following results were obtained. 1) There were 9 cases of impetigo and 15 cases of erysipelas with typical clinical manifestations and age distributions. 2) It seemed that some of the skin infections were caused by group A streptococci whose M-types were different from those of upper respiratory infections typically occurring in Japan. 3) The type distribution of group A streptococci found were quite similar to those isolated in Thailand or Malaysia. 4) There were found group A streptococci exhibiting unique combinations of T- and M-types, such as T11 and M9, T11 and M62 or T13-49 and MOD8 (Provisional type). 5) As for serodiagnostic method, ADNB (anti-deoxyribonuclease B) titer reflected infection by group A streptococcus only, while ASK (anti-streptokinase) and ASO (anti-streptolysin O) reflected not only group A streptococcal infections but group G infections as well.

[Isolation of group A streptococci from pharyngitis patients of all ages--studies from the clinical and epidemiological standpoint].

During the period from June 1981 through Dec. 1985, isolation of group A streptococci was attempted from throat swabs of pharyngitis patients of all ages, who visited a clinic in the central area of Yokohama-city. The data were analysed clinically and epidemiologically. The results were summarized as follows. 1) Group A streptococci were isolated from 85 (30.5%) out of 279 patients with pharyngitis. This is almost within the range of other reports. 2) During one year in the study period, no isolates of group A streptococci were obtained from throat swabs of 32 controls (healthy persons working in the clinic or patients without pharyngitis). 3) The isolation rate correlated with the presence of pharyngeal purulent exudate and also with high maximum body temperature after onset of the illness. The isolation rate was significantly higher in patients with these two signs than those without them. Therefore, these two signs are useful to predict group A streptococcal pharyngitis prior to laboratory examinations. 4) The isolation rate was high in the age groups under 10 and from 30 to 39. 5) The isolation rate was high in winter and low in summer. 6) The typing test revealed T types 13, 28 and 4 to be relatively frequent isolates.

Antigenicity of group B Streptococcus strain "M9" and its prevalence in Japan.

Serological typing of group B streptococci is important for the epidemiological study of group B streptococcal infections. These days, non typable (NT) strains by conventional serotypes were on an increase. In 1984, strain "M9" was isolated from a pregnant woman in Meijo Hospital, Nagoya City; herein the antigenicity and prevalence of strains typed as "M9" were investigated and discussed. The results obtained were as follows: 1) It was confirmed that strain "M9" had a new polysaccharide antigen, different from conventional types, Ia, Ib, II, III, IV and V, type candidate NT6 and type candidate 7271, as found by precipitation and precipitation absorption reaction. This procedure, moreover, was useful for differentiation type candidate NT6 and 7271 from "M9" because of their provisionality. 2) Group B streptococci typed as "M9" were isolated not only from carriers but from patients who were newborn babies and suffered from sepsis. 3) Strain "M9" was not necessarily located in Nagoya City but in Chiba and in Kyoto, this type was isolated from clinical materials already in 1979. 4) It was observed that polysaccharide "M9" liked to combine with protein "R" and without other proteins, as our collection extends.

[A study of the antigenicity of group A streptococcus strain "Matsuyama 2166" and its prevalence].

Antigen analysis of group A streptococcus strain, "Matsuyama 2166", which had been typed as T12-28 (by the T-agglutination method), MNT (nontypeable by the M-precipitation method) using conventional typing sera was examined by the precipitation and precipitation absorption technique. The prevalence of group A streptococci, typed under the name "Matsuyama 2166" was also investigated. The results were as follows: 1) The strain "Matsuyama 2166" is OF (Opacity Factor) (+) and its serological components consist of M "Matsuyama 2166" antigen, which is unique in our collection of M-types, and T28 antigen as a major antigen along with T12 as a minor. 2) Out of the group A streptococci typed as MNT, 96.6% of the streptococci were types as T12-28 and 96.5% of T28 by conventional typing sera were strains to be typed as M "Matsuyama 2166" using the newly prepared M "Matsuyama 2166" typing serum, suggesting the great advantage to M-typing rate of T28 strains. 3) Group A streptococcus M "Matsuyama 2166" was also found in isolates from Thailand or Malaysia. It is interesting that T-types found in those isolates seems to be a little different from the T-types isolated in Japan. These results showed that there was the difficult problem when we did the speculation of M-type from the result of T-type.