An initial suspect was climate change. Then, cell phones and pesticides took the hot seat.

Now, scientists are fingering their latest culprit in the dramatic disappearance of honeybees: a fungus and virus team, according to a paper published in the online science journal PLoS One.

Colony collapse disorder has been on the radar since 2006 and has been identified worldwide. In “collapsed” colonies, adult bees disappear amid untouched food stores.

Colony Collapse Disorder has economic ramifications, since bees pollinate crops worldwide.

Enter the latest potential villains. The virus affects bees’ abdomens, often turning their tissues a purplish tone. The fungus, which also targets the bees’ guts, is called Nosema ceranae.

Combined, it seems the duo prevent bees from getting enough nutrition.

This theory is being hailed as one of the closest to solving the bee mystery yet. Scientists found the presence of the virus and fungus in every collapsed colony the group studied.

While the exact causal relationship is unknown, an initial infection of one could stress a bee’s system, making it vulnerable to the subsequent follow-up punch.

A partnership between military scientists and entomologists is responsible for the latest research. Their past collaborations have produced the Manhattan Project and land mine-detecting honeybees.

Next up is more research to determine how Colony Collapse Disorder can be stopped.