What does this symbol mean?

[WaflHead]

Can anyone tell me what the odd yellow symbol in the center of this screenshot means? It's shown up in two separate games. I'm playing with the Expanded Universe customization with tons of additional mods downloaded from the mod forum.

[Bingeling]

I think it signals some nastiness going on. A plague/virus infection (nasty event).

[WaflHead]

Mystery solved. Thank you Bingeling.

[Spacecadet]

Yeah, that's the Bio Hazard symbol and designates that a Plague of some sort is in progress.

[ehsumrell1]

Quarantine that planet QUICKLY! (i.e. on Colony screen change racial popualtion priority from
Assimilate or whatever it is to Do NOT Accept. Then monitor until plague/virus event is over
and reset the planet settings)

[WaflHead]

I will do that right away, thank you for your advice.