Disease can change body odor, and dogs have been trained to "sniff out disease" [0][1] (i.e. detect via smell) for years. Various researchers have been working on robot noses that would be able to do the same.[2] Presumably a widespread and/or less expensive version of this "robot nose" is what doku means by "AI nose sniffs out many common diseases".
[0] https://www.nature.com/articles/d41586-022-01629-8
[1] https://www.discovermagazine.com/the-sciences/how-do-dogs-sn...
[2] https://bigthink.com/the-future/robotic-nose-smartphone-dete...