How would this change the way we viewed criminals? (And, for that matter, the cranky uncle who drives everyone nuts at Thanksgiving?) My hypothetical above does not claim that the criminals and the cranky were powerless to resist these urges, just that it was harder for them than for the non-infected. I would contend that society would be split between those who felt those with the virus had been dealt a bad hand, but their behavior was still their fault, and those who would argue people cannot be held really responsible for behavior driven to a large extent by an outside influence.
I bring this up because of a brief article in New Scientist that outlines the link between a mouse virus and Chronic Fatigue Syndrome (CFS). The science is clearly at an early stage, and previous attempts to link CFS to a virus have not borne out. But here is the key finding:
Shyh-Ching Lo of the Food and Drug Administration in Bethesda, Maryland, and colleagues found that blood samples from 32 of 37 people with chronic fatigue syndrome contained "polytropic" murine leukaemia virus-related fragments, compared with only three of 44 healthy blood donors.
Now, having done some work in this topic, I can say that many physicians, especially older male physicians, put CFS in a bucket of "women's conditions", along with related syndromes like Fybromyalgia and Restless Leg Syndrome. They tend to believe that the women in their care have underlying psychological problems that are manifesting themselves in these syndromes. That some anti-depressants have proven helpful in alleviating several of these syndromes reinforces their view. To say these physicians are dismissive of these problems and these patients is an understatement.
Patients would widely embrace the identification of a 'real' cause, and would undoubtedly demand a level of care and support for their condition far beyond what they receive today. But notice that not every CFS patient has the virus, and not everyone with the virus has CFS. That implies either that the virus may contribute to the syndrome without fully causing it, or that the reaction to infection might vary enough that a significant number of the infected aren't noticeably sick. (And would this be so surprising? After all, people react very differently to infection by the same cold viruses.) But if, for example, 25% of the people infected with this mouse virus are not noticeably fatigued, and another 50% are fatigued or lethargic to a degree, but are still able to function, many people are going to dismiss the 25% who are most affected as lazy, as milking their diagnosis. And it will be hard to prove the truth either way.
As the science of health continues its amazing advance, we're going to learn more and more about the environmental influences (viruses, bacteria, chemicals, etc.) that impact human performance. If pre-natal pollution exposure lowers IQ, should the less intelligent from dirtier environments be compensated, or get preferential treatment at schools? If certain gut flora lead to obesity, do we give them health coverage for bariatric surgery? With each new learning or theory, we move farther from the notion that people should be held accountable for their choices, and closer to a world where every personal failure is attributed to an outside force. It may be hard work to preserve the notion that we are masters of our own lives.