News Crippled fungus acts as vaccine By John Travis October 27, 2004 at 5:09 pm - More than 2 years ago Share this:Share Share via email (Opens in new window) Email Share on Facebook (Opens in new window) Facebook Share on Reddit (Opens in new window) Reddit Share on X (Opens in new window) X Print (Opens in new window) Print Even if your immune system can fend off harmful bacteria, viruses, and parasites, you still have fungi to fear. Worldwide, millions of people suffer debilitating and even fatal fungal infections. People with weakened immune systems, such as the elderly and AIDS patients, are particularly susceptible. Despite this threat, there’s not a single fungal vaccine available for human use, and microbiologists were for a long time pessimistic that there ever would be.