Jpn. J. lnfect･ Dis･, 54, 2001

Laboratory and Epidemiology Communications

Subgroups A and B Respiratory Syncytial Virus Isolated
in Ehime Prefecture, 199511999
Reiko Kondo*, Kimi Ybshida, Yasutaka Yamashita, Mitsuaki Oseto,
Tadao Asai, Hiroo Inouye, Shozo Nakanol and Yoshiro IshimaruI
Ehime Prefectural Institute of Public Health and Environmental Science,
Sanban‑cho 8‑234, Matsuyama 790‑0003 andJIshimaru Pediatric Clinic,

Sanban‑cho 6‑5‑1, Matsuyama 790‑0003, Ehime
Communicated by Hiroo lnouye(Accepted September 10, 2001)

Respiratory syncytial virus (RS virus) is one major causative

subgroup A (〟 ‑ 107) or a (〟 ‑ 47). Follow‑up ofmonthly

agent of infantile acute resplratOry infection during the winterisolation of RS virus is shown in Fig. 1. RS vims was most

season. lt often causes serious lower respiratory tract infec‑

frequently isolated during the winter season, and isolation

tions, such as bronchiolitis and pneumonia. There are twoduring the summer season was sporadic･ These subgroups

subgroups of RS virus, group A and group B. Information

co‑existed throughout the study period, and contributed toregarding the distribution of these two subgroups during

epidemics. From the autumn of 1998 to early 1 999, there was

epidemic seasons has been scarce. Our recent studies on thea dramatic increase in the number of RS vims isolates, andstrains isolated in Ehime Prefecture in 1 995‑ 1999 revealed aparticularly in that of subgroup B isolates･ Figure 2 showstransition from group A to group B toward the end of 1998･

the prevalence of each subgroup during the epidemic season

That data is detailed in this report.

Clinical specimens were collected from outpatients in afrom 1995 to 1999. Until the 1997/1998 epidemic season,
subgroup A was predominant, at which time subgroup B

pediatric clinic in Matsuyama City. Pharyngeal swab specimens

became predominant. This observation is in line with reports

obtained from infants with acute respiratory infections were&om Japan (2,3), Europe, and Ame.rica (4,5) in that, although

inoculated to FL, RD‑ I 8S,and Vero cells cultured in roller tubes.

both subgroups may cause respectlVe epidemics in the same

Viruses were identified by neutralization or by fluorescentseason in the same area,血e predominant subgroup altemates･

antibody method. Subgro叩S Were detemined by the method

Most patients from whom RS virus was isolated were underof Milaan et al.; i.e., RTIPCR amplification of nt 943‑1 160

6 years ofage･ Patients under 1 year orage acco雌ted f♭r 56%

0rRS virus genome (the 3'‑end of the lB gene and the 5′‑of cases with subgroup A and 68% of cases wi血subgroup a,end of the N gene) followed by Dot blot hybridization withand the difference in the percentage was not slgnificant･subgroup specific probes ( I)･

Among 107 cases,known clinical manifestation including 1 3During the study period (January 1995 to February 1 999),

pneumonia, 72 bronchitis, 1 5 upper resplratOry tract inflamma‑

1 54 RS virus isolates were obtained from patients with acutetion, and 7 others, there was no slgnificant correlation between

resplratOry infections. All the isolates could be typed into

the clinical manifestation and subgroups.

Salel〇SこOLOq∈nu

211 0 5 0 5

1

3

1995

5

7

9

ll

1

3

5

7

9

ll

1996

1

3

5

1997

7

9

ll

1

3

5

7

1998

Fig･ ll Isolation ofRSV subgroups during January 1995 and February 1999･*Co汀eSpOnding author: Fax: +8ト89‑947‑1262, E‑mail: kondo‑

reiko@pref. ehime.jp

155

9

ll

1

1999

Jpn. J. Infect. Dis., 54, 2001
l8Subgroup A I

llSubgroup ら 】

Jaロ.,95‑Jun.,95

Jul.,95‑Jun..96
Jul"96‑Jun..97
Jul..97‑Jun..98

JuL98‑Jun"99
40

30

20

1

0

0

0

1

0

20

30

40

Fig1 2･ Distribution ofRSV subgroups detcctcd over five epidemic seasons･and Chiba, S. (1993): Three antigenic variant groups in

REFERENCE S

human respiratory SynCytial vims subgroup B isolated
in Japan. Arch. Ⅵro1., 128, 55‑63･

1. Milaan, A. ∫. V, Sprenger, M. J. W., Rothbarth, H･,( 1 994): Detection of resp.iratory syncytial virus by RNA‑

4. Mlinaric‑Galinovic, G., Chonmaitree, T., Cane, A. P.,
Pringle, R. C. and Ogan, L P. (1 994): Antigenic diversity

polymerase chain reactlOn and differentiation of sub‑of respiratory syncytial virus subgroup B strains circulat‑

Brandenburg, A. H., Masurel, N･ and Class, E･ C･ J･

lng during a communlty Outbreak of infection. J. Med･

groups with oligonucleotide probes. J. Med. Ⅵrol･, 44,

Viro1., 42, 380‑384.

80‑87.

Chiba, Stand Ogra, P･ L･ ( 1 988)‥ Occurrence of respiratory

5. Peret, T. C. T., Hall, B･. C., Sclmabel, C. K., Golub, A. J.
andAnderson, J. L. ( 1 998): Circulation pattems of geneti‑

syncytial virus subgroup A and B stralnS in J叩an, 1980

cally distinct group A and B strainsof human respiratory

to 1987. ∫. Clin. Microbio1., 26, 1171‑1174.

syncytial virus in a community. J. Gen. Viro1., 79, 2221‑

2. Tsutsumi, H., Onuma, M., Suga, K., Honjo, T., Chiba, Y.,

3. Nagai, K., Tsutsumi, H., Yamazaki, H., Pattamadilok, S･2229.

156