Zombies caused by fungal infections
Well, make sure that you add National Geographic to the list of sites you search for Microbes in the News bonus point opportunities. Today’s summary comes to us from the Amazon Rainforest, and the work described at Nat Geo was published this month in the journal PLoS ONE. Entomologists from right up the road at Penn State University had noticed that ants demonstrated a large variety of fungal growths on them (picture at right.) Once the ant has been infected, the fungus apparently triggers behavioral changes in the ant which cause it to spread the fungus over a wider range. The ant then dies, which allows the fungus to spread its spores to new locations.
The fungal species isolated from infected ants were a newly described group called Ophiocordyceps. Many related species are common endoparasites that infect many insects; Cordyceps unilateralis infects ants and causes them to climb a plant and die there. Another related species, Cordyceps sinensis or the Caterpillar fungus, has been used as a traditional medicine in Chinese culture. An active component from this fungus called cordycepin appears to have multiple biological effects in humans, including potential anticancer properties, antidepressant effects, and hypoglycemic effects. The end of the Wikipedia entry notes that shroom hunters in Nepal can earn $900 an ounce for Cordyceps, so here’s a money making opportunity for work study students.
BONUS: We had an earlier bonus opportunity with fungal infections at the start of the term, but let’s stick in another since no one will comment without a carrot in front of them. Are there other instances of microorganisms causing behavioral changes in the host that they infect?