Hong Kong extended a compulsory quarantine by an extra seven days to 21 days for all visitors.
Flight Bans for UK and South African Travelers.
Hong Kong tourist visa is not required for citizens of Switzerland for a stay up to 90 days.
Check with your airline in case you have connecting flights overseas as part of your journey to Hong Kong. It may be the case that countries you pass through en route to your destination may require a separate transit visa. Please refer to visa requirements of the specific country.