Yes. Your employer could choose (but is not obliged) to take you off of sick leave and SSP, furlough you and pay you 80% of your salary. 


Those will short-term illnesses and those isolating because of COVID-19 should be on sick leave and receive SSP.  For those isolating due to COVID-19, SSP is payable from day 1 rather than the normal day 4; and employers can reclaim 14 days of SSP from the government.