Abstract: The present invention relates to a method for reducing pathogens in and/or on a subject, comprising exposing the subject to infrared radiation. The source of the infrared radiation comprises in particular a carbon crystal heating element, which can be applied to and/or positioned in the vicinity of a subject. In particular, the method includes treating infections in a tree, such as bleeding canker in horse chestnut trees and/or canker in kiwifruit trees. The method may further include disinfecting articles, for example for pasteurising or sterilising foodstuff.