That's an excellent point. Most people around the world who are at risk of HIV, for example, are extremely poor. They don't have private insurance coverage. Governments could make the decision to invest in very inexpensive generic drugs that would help prevent some of these diseases. Individuals also, if they're counselled properly, may decide that an aspirin is a couple of cents a day, so people could invest that in their own health care. It's something within reach. Both government funding of these approaches, as well as individual funding if the bar is low enough, are accessible.
