The present invention provides a treatment apparatus. The apparatus contains a reservoir or generator for a treatment solution, a mechanism for delivering the treatment solution to a wound site, and a mechanism for applying the solution to a wound, tissue, bone or surgical cavity for treatment. The apparatus may apply the solution (e.g., a solution containing hypohalous acid) with, for example, an occlusive wound dressing, pulsative lavage device, hydrotherapy, hydrosurgical device, and/or ultrasound. A waste container may be operably connected to the apparatus for collecting waste from the wound by run-off, or by applying negative pressure (e.g. a vacuum). Because the apparatus of the invention can optionally be portable or mobile, the invention is suitable for use in hospitals and nursing homes, as well as for home wound care. The invention also provides a method for treating a wound (or other area needing treatment), and/or for reducing wound bioburden, by supplying a hypochlorous acid solution to the site, such as a wound colonized or infected with drug resistant bacteria, before, during, or after negative pressure wound therapy.