World Health Organisation officials have dismissed calls for this summer's Olympics to be postponed or moved.

150 scientists have written to the WHO claiming the Zika outbreak makes it unsafe to hold the games in Rio.

The virus is usually transmitted by mosquitoes and is linked to birth defects. 

But the W.H.O. says shifting it won't significantly alter the spread of the virus.

Professor of medical microbiology Mark Fielder says competitors and fans travelling should not be a problem: