The Boeing 777 was on its way to Kuala Lumpur from Amsterdam when it crashed near the village of Grabovo close to the border with Russia, with no survivors among the 298 passengers and crew on board.
Swiss joined other airlines on Thursday evening in announcing that it will largely avoid Ukrainian airspace from now on by diverting flights over the south of the country, above the Black Sea.
Only the Bangkok-Zurich route is affected by the change, explained Swiss spokesperson Susann Mühlemann.
German carrier Lufthansa, which owns Swiss, has also said it will avoid the area, having diverted four flights on Thursday evening,
Air France and Italy’s Alitalia are among other carriers rerouting flights.
Prior to the crash several airlines had already been avoiding the area because of security concerns.
South Korea’s two main airlines – Korean Air Lines and Asiana Airlines – said they had modified routes to avoid eastern Ukrainian airspace since the beginning of March, when Russian forces entered Crimea.
Australian airline Qantas and the Taiwanese carrier China Airlines have also been rerouting planes for several months.
The route flown by Malaysian Airlines flight MH17 is the most common route for flights from Europe to South East Asia, according to the European Cockpit Association.
At the time of the crash the route had been closed by the Ukrainian authorities up to flight level 320, said the BBC, but the Boeing 777 was flying above that at flight level 330 (33,000 feet).
European flight safety body Eurocontrol said it had now closed the country to all passenger flights.
The majority of passengers among the 298 people on board the Malaysian Airlines flight were Dutch.
Some 27 Australians, nine Britons, one Canadian and one New Zealander were also on board.
As yet no Swiss passengers have been reported, though the nationality of 38 passengers remains unknown.
It’s the second disaster to hit Malaysian Airlines this year, after flight MH370 disappeared in March on its way to Beijing from Kuala Lumpur with 239 people on board. It has never been found.