With an hour remaining in Oz markets on Friday, Donald Trump announced that he and wife Melania had been diagnosed with COVID-19. The news sent US futures tumbling 2% within an hour, albeit to recover to a degree soon after. With several hours before US markets open, all signs point to more volatility to come. Questions are pouring out - Can Trump campaign? Will the election be delayed? Was Biden exposed at the presidential debate? The bombshell is yet another layer of uncertainty in an extremely volatile period for world markets. The late ASX selloff was hardly surprising as local investors looked to de-risk before the weekend. While Australian markets were relatively subdued and several Asian markets were closed for holidays, and the Friday session typically quieter for volumes, investor reactions could have been worse. All eyes will be on the US’ Friday trade and there is little doubt the news will dominate coverage over the weekend.