British Health officials have declared it a national incident
In Britain, traces of the polio virus have been found in sewers in east London.
Experts have noted the discovery is the first sign of transmission in the UK since 1984.
The discovery in Beckton has prompted authorities to declare a national incident, as they attempt to track cases.
The virus - which in rare cases causes paralysis - has been mostly eradicated worldwide due to vaccines.
Sky's health correspondent, Ashish Joshi, says occasional cases are not unheard of:
Donald Trump Says "Board of Peace" Has Reached An Agreement For Disarment Of Hamas
Daniel Kinahan Set To Face Trial In Ireland
"All Of Europe" Could Be On Fire In Coming Days, Says EU Agency, As Two Firemen Die In Greece
Fuel At The Pump Could Reach €2.30/L If Middle East Conflict Continues
Google Hit With €890M Fine By European Commission
Andy Burnham Sworn In As British Labour Leader
Phased Social Media Age Restriction Being Proposed By European Commission In September
US Launches Fresh Strikes On Iran
