Virus uses zombie caterpillars to spread

Wednesday, December 24, 2014, 10:53 AM - A new study has found a virus capable of "zombifying" caterpillars and using them to propagate the infection.

Published today in Biology Letters, the study describes the method of infection of a specific baculovirus. The virus manipulates its caterpillar host, forcing it to follow the light. The insects climb to the top of the plants dying, and the virus rains on the foliage below, potentially infecting more caterpillars.

DON'T MISS:  New breakthrough in the war against bed bugs

To make sure that the virus was using this method, scientists placed infected caterpillars in light and dark rooms and compared both to healthy samples.

They found that the healthy insects climb up and down the plants, stopping short of the top. In fact, as healthy caterpillars get older they stay closer to the base. Infected caterpillars that were in a dark room, displayed similar behaviour, not climbing toward the top. It was only the infected ones that had access to daylight that died in this peculiar manner.

Scientists concluded that the virus infects the host and controls its reactions to light.

Night of the crawling dead

Caterpillars aren't the only insects being controlled. A parasitic fungi has also been shown to have the ability to alter ants' behaviours. Surprisingly the fungi only likes to control one specific kind of ant. When encountering their ideal host, the fungi releases a cocktail of behaviour-controlling chemicals. But if instead, a different kind of ant is used the fungi doesn't react.

This discovery could be key in understand the process the parasite uses to infect the host. The molecular mechanisms would have to be more complex than initially anticipated

MUST-SEE: Check out this zombie found at sea