"There's no evidence that G4 is circulating in humans, despite five years of extensive exposure," he said on Twitter.
"Ma jiraan wax caddeyn ah oo ah in G4 uu ku faafayo aadanaha, inkasta oo shan sano uu si baahsan u soo muuqanayay," ayuu ku yiri Twitterka kadib daabacaadda warqadda.