I have previously discussed a fungus (Ophiocordyceps) that attacks ants and takes over the brain of the ant. The fungus manipulates the behavior of the ant so that the fungus can be widely disseminated to infect other ants. This interaction could be detrimental to ant populations. However, fungi do not totally wipe out the ants. Many ants survive despite the presence of the Zombie creating fungus. Are there factors that protect the ants from becoming Zombies?
Andersen and colleagues have published a paper in the Journal, PLoS One, that describes another fungus that attacks Ophiocordyceps. This fungus makes the Ophiocordyceps sterile, incapable of producing spores. Ophiocordyceps successfully produces spores in only about 6 percent of the ants infected. Perhaps Ophiocordyceps needs to create Zombies that will transmit at a high rate, because Ophiocordyceps has a low rate of successfully producing spores?
This is an interesting system that is being studied as a model of how disease spreads through a society. Models of disease spread in ants may be applicable to spread of disease in humans.