zannamarie
When I originally read this I thought you meant the body language your body was sending you about the disease (or whomever's body was sending them about the disease since you didn't specify the disease was yours).
I tend to take a lot of body messages literally - 'having problems stomaching something' (issue with stomach/digestion), 'not being able to handle something' (issue with hands), 'having problems standing up to something/one' (back issues) and thus translate whatever body issue/disease back into my life so as to address it.
However, I see you mention the insect guide actually hopping back and forth so I think you meant you wanted to interpret the insect's body language. I would go along with Mi-Shell's suggestion of how does that action translate to the natural actions the insect would make. Or if it's not an action the insect might normally take then is there a book or movie or something other depiction of the insect (in a movie, book, fable, etc.) where it might be doing that--and how might that relate? I would presume that if the insect is your guide then it would do its best to translate information in ways it would think you would understand.
Insects are relatively tiny compared to the world in which they inhabit, but then again so are blood molecules or other organisms in our bodies (ie our body is the world in which the blood and other organisms inhabit) so perhaps the message is a smaller part of something which would explain the bigger message. Rather than relating the hopping of an insect to the hopping of a person think butterfly effect where something seemingly small has more of an effect when magnified. So something small may have been the start of the disease, but now it is being magnified to the point the disease is noticed.
Just a few ideas.
