An iron chelator might be worth considering in the case of such virulence. A chelator that does not affect the iron in hemoglobin.

This following quote deals with cancer cells; but seems like IP6 would at least be an iron withdrawal agent for pathogens requiring iron. Unfortunately, it also chelates zinc and calcium; so should be taken apart from mineral supplementation. IP6 is found in most high-fiber foods. Manufacturers use rice bran.

"Nature’s most effective iron-chelating molecule is inositol hexaphosphate (IP6), found naturally in seeds and bran. IP6 is a selective agent against cancer cells. Because cancer cells are high in iron content, IP6 directs most of its attention to abnormal cells. IP6 selectively removes iron from tumors cells, which deprives them of their primary growth factor. IP6 does not remove iron from red blood cells which are tightly bound to hemoglobin. Unlike cancer drugs, healthy cells are not affected with IP6, so IP6 has very low toxicity. [Deliliers GL, British J Haematology 117: 577–87, 2002]"
http://www.lewrockwell.com/sardi/sardi39.html