One well-connected infectious disease expert told me the Health Department is being vague about who has what underlying condition, because, 'For about 50 percent of those who died, they have a plausible explanation, and 50 percent they don't.' The city says that's 75-25, but we have to take their word for it. Some of those who've died have been in their 30s and 40s. That's certainly plausible for someone with a severely compromised immune system, from HIV or cancer; it's a bit more mysterious if those people 'merely' had diabetes or asthma, unless they were pretty advanced. As the New York Times pointed out, if you add up all the underlying conditions, you might account for one in three city residents. How worried should they be about getting swine flu.
The same infectious disease expert, who spoke on background because he works with the Health Department but wasn't authorized to speak, said s/he could understand why officials wanted to be vague about who had what conditions: it can be difficult for people to accept that there's no current explanation for why so-and-so died, and uncertainty can lead to panic, especially when stoked by the media.
Clearly, some media traffic in nuance more than others, and clearly the public often tunes out details it doesn't want to hear. Vast numbers ignored pleading to stay away from ER's unless they were severely ill and/or had an underlying condition. But, ultimately, officials are going to have to admit they can't explain everything. They can get away with it this time, because the numbers are relatively small and the illness relatively mild. But if they continue to downplay conditions if things ever get much worse, you'll have an uproar. We expect officials to behave that way in China, not here.
One last thing: is there value to knowing more about the individual cases, and can that information be shared while protecting their privacy? Open almost any medical journal, and you'll find ample information about anonymous patients. They're called case studies, and there's a good reason why they're a main-stay of medical research and literature. These cases don't provide statistically significant information, but they help us understand what conditions contribute to illness, and they let us work through what's known and unknown.