This was explored in an earlier Canon Fodder, that issue saw Harvest join the Universe page.TheKiltdHeathen wrote:
Actually, a second question comes to mind. At the artifact, Wamik says "What if the infection defiled the relic?" - what infection? I always figured he meant Humanity, as the Flood wasn't present on Harvest, but did they know about the Flood even then?
"Before the activation of Halo, the Forerunners knew Harvest as CE-309-8 d. A minor asset in their vast interstellar domain, the planet was used as a Shield waystation facility, complete with Flood research/containment centers and administrative nodes that directed Forerunner defenses in the surrounding region. Covenant excavations later revealed several of these Forerunner structures."