Pubmed?
Beer is generally considered safe (in terms of microbes at least) but this is not simply due to the boiling. The pH, anti-bacterial properties of the hops, and ethanol concentration all contribute.
However, do you really want, in a class on Global Health Hazards to be promoting an alcoholic beverage as a cure for water borne diseases? The other health hazards that accompany beer probably do not make it the best solution for say giving to infants in third world countries.