I believe his comments were more politically motivated... If you read his Feb 8th Science Editorial Science for the Globe, you will see his motivation appears to be driven by the re-dispersement of scientific funding across a wider breadth of issues. Since such a large amount is devoted toward HIV research, this is a good place to look at for re-distribution, especially since the NIH funding will not increase within the last year of the Bush Administration..
Here is a quote for David Baltimore's editiorial referenced above...
"The AAAS annual meeting will explore many of these issues and, as a biologist, I am gratified that the program will also emphasize health. Bringing health benefits to the less-developed world has become a philanthropic priority for wealthy Americans such as the Gates family and for the governments of many developed countries. The concentration of resources for treating and preventing AIDS is heartening. However, as HIV researcher Daniel Halperin recently emphasized in the New York Times, donors could take a more balanced approach to improving health in the world's poor countries. Cleaning the air and water, treating sewage, dealing with diarrhea, and mounting immunization programs are all needed. So is improving the availability of health practitioners to treat non-HIV-related disease, which cannot be ignored even though AIDS is so widespread."