A rising tide is said to lift all boats. A crashing wave can often sink a few of them too. As emerging-market bonds listed from another sharp selloff, other areas perceived risky by investors have been caught in the swell.

Average yields on European high-yield bonds, for instance, are about 0.2 percentage points higher than they were last Wednesday, closing Tuesday at 4.74%, according to a Markit index. That's the largest short-term jump since June when yields on these so-called junk bonds rose more than 0.5 percentage points in a week-again prompted by a shakeout in emerging markets.