I've been thinking about the notion of disease contests. This idea is well-known among medical anthropologists, and the contest operates on a number of social levels. First, there are professional contests among different classes of healers. Paul Brodwin demonstrates this among the different healers in (postcolonial) Haiti -- voodoo priests, Catholic priests, and Protestant healers. Paul Starr's seminal book also depicts this contest among homepaths and allopaths in the mid-to-late 19th century in the U.S. Jean Jackson describes the contests that go on in the space of chronic pain.
These contests are quite "real" and have significant social consequences. Chronic pain patients are inherently disadvantaged across a variety of pathways, and they frequently "lose" these contests and have their pain delegitimized.
Don't underestimate the power of stigma and social exclusion. In this study, one of my favorites, the terminal lung cancer patients, amidst their suffering and their mortality, say that these would be tolerable but for the stigma they suffer for being lung cancer patients (the subjects were mostly among the 10% of all lung cancer patients whose cancer is not related to smoking). Chronic pain contests often divide families, and I have seen this personally.
Anyone who doubts disease is contested space should consider the medicalization of society, and the arguments over the phenomena construed as Gulf War Syndrome. That disease is socially contested -- often, though not always along existing social fault lines and class differences -- itself demonstrates the social nature of disease, that the experience of illness itself cannot be defined along "biological" lines as if the latter were hermetically sealed off from social influences.
Much is at stake in thinking about disease, about medicalizing phenomena, and the process of construing disease and illness is just so important, IMO. I'm biased, but medical anthropologists have flocked to the study of disease in culture because learning about the meanings a given culture attaches to illness is a rich vein in explicating some of that culture's most cherished and significant beliefs.
In any case, I've experienced this seemingly dry, erudite phenomenon in my life quite significantly recently. That's cryptic, but that's about as much as I can say here. Suffice it to say that I think it is true that disease is socially contested space.