Efficacy of antibiotic prophylaxis for intrafamilial transmission of group A beta-hemolytic streptococci.
BACKGROUND
The role of chemoprophylaxis for household contacts of patients with acute streptococcal disease is uncertain.


METHODS
The subjects were 1440 sibling contacts of 1181 index patients with group A beta-hemolytic streptococcal (GABHS) pharyngitis. Instances of subsequent GABHS pharyngitis in sibling contacts who received chemoprophylaxis and in a control group without prophylaxis were compared.


RESULTS
Of the 948 siblings in the prophylaxis group, 507 were treated with cephalosporins and 441 were treated with penicillins for 3 to 5 days. Subsequent GABHS pharyngitis occurred within 30 days in 28 (3.0%) of the 948 siblings in the prophylaxis group and in 26 (5.3%) of the 492 siblings in the control group. Among siblings in the prophylaxis group, subsequent GABHS pharyngitis occurred in 9 (1.8%) of the 507 siblings in the cephalosporin prophylaxis group and in 19 (4.3%) of the 441 siblings in the penicillin prophylaxis group. When these data were each compared with that in the control group (5.3%), a significant statistical difference was seen in the cephalosporin prophylaxis group (P = 0.003) but not in the penicillin prophylaxis group (P = 0.542). Only 5-day cephalosporin prophylaxis showed significant reduction in the rate of subsequent GABHS pharyngitis compared with that in the control group (P = 0.002).


CONCLUSIONS
In view of the low incidence of subsequent GABHS pharyngitis in the nonprophylaxis group, the usual self-limited nature of GABHS pharyngitis, the cost of prophylaxis and the risk for selecting resistant flora, routine chemoprophylaxis against GABHS pharyngitis for sibling contacts is not recommended.
Kikuta
Hideaki
H
Pediatric Clinic, Touei Hospital, Sapporo, Japan. hide-ki@touei.or.jp
Shibata
Mutsuo
M
Nakata
Shuji
S
Yamanaka
Tatsuru
T
Sakata
Hiroshi
H
Fujita
Kozo
K
Kobayashi
Kunihiko
K
D000293:Adolescent; D019072:Antibiotic Prophylaxis; D002511:Cephalosporins / Q000627:therapeutic use; D002648:Child; D002675:Child, Preschool; D018562:Disease Transmission, Infectious / Q000517:prevention & control; D005192:Family Health; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D010406:Penicillins / Q000627:therapeutic use; D010612:Pharyngitis / Q000382:microbiology / Q000517:prevention & control*; D013223:Statistics as Topic; D013290:Streptococcal Infections / Q000382:microbiology / Q000517:prevention & control* / Q000635:transmission*; D013297:Streptococcus pyogenes / Q000187:drug effects*
D002511:Cephalosporins; D010406:Penicillins