“…The ASO titre may be found to be raised in apparently normal individuals; in one study (Lawy 1960) 12% of sera examined showed ASO titres of 200 u./ml. Subclinical infections with Group A streptococci do occur (Rantz 1945, Mozziconacci et al 1966 and it is assumed that this may account for some, perhaps all, instances in which ASO titre has unexpectedly been found to be high.…”