It's not. It's "bouloche" -- https://fr.wiktionary.org/wiki/bouloche
> When my kids brought home notices telling me to check their hair for “poux” (pronounced “poo”), I correctly deduced that it meant lice. But later, in a first-aid course, I was perplexed when the instructor told us to immediately check an unconscious person for “poux.” He was telling us to check for “pouls” — a pulse, pronounced identically.
There are homophones in many (most? all?) languages; but in this case "poux" are almost always plural (les poux / des poux) whereas a pulse is always singular (le pouls).
"Check his pulse" would be said as "vérifiez son pouls" and "check if he's got lice", "vérifiez s'il a des poux": it seems hard or impossible for the author to mix them up.