Does 'cures' ability work for all adjacent units?

Both the in-game help and this wiki page say only:

A curer can cure a unit of poison, although that unit receive no additional healing on the turn it is cured of the poison.

Basing on the exact wording (a curer can cure a unit) it would seem that it works only on one unit, but corresponding text for "heals" abilities also uses singular form (a unit cared for by this healer) and they work for all adjacent units.