Coronavirus infections are rising in several eastern European countries as Thailand prepares to open up to vaccinated foreign tourists.
Poland reported 8361 daily COVID-19 cases and 133 deaths on Wednesday, with the number of new infections reaching the highest level since late April.
Bulgaria's tally of infections has risen by 6813 in the last 24 hours, a record daily increase as the European Union's least vaccinated country grapples with a fourth wave of the pandemic.
The Czech Republic reported 6274 new cases, almost doubling in a week.
Hungary reported a jump in daily cases to 3125, its highest daily tally since April, as the government urged people to take up vaccines that are widely available.
Ukraine's health minister urged more people to get their COVID-19 shots as coronavirus deaths hit a daily record of 734 on Tuesday, with hospitalisations up more than a fifth on the previous week.
While the European Union's average vaccination rate is about 70 per cent, countries in central and eastern Europe hover around 50 per cent and less.
Thailand held a dry-run on Wednesday for its long-awaited, quarantine-free reopening to vaccinated travellers as the country rushes to reboot an industry battered by an 18-month hiatus in international tourism.
At Bangkok's Suvarnabhumi airport, Thailand's main gateway, airport staff and health and immigration officials ran a simulation of the arrival of a plane full of visitors, to test out electronic screening measures.
"All the passengers will get their QR code checked by the Department of Disease Control," Kittipong Kittikachorn, the airport's general manager, said.
"It will include all the details about insurance, vaccine certificate or hotel booking."
The pandemic's effect on tourism in Thailand has been particularly severe, with authorities targeting just 100,000 arrivals this year compared with nearly 40 million in 2019.
Since July, Phuket and Samui islands have been re-opened in pilot projects.
Among the Asia-Pacific's most visited countries, Thailand has lost about three million tourism-dependent jobs due to COVID-19.
The slowdown, however, was not entirely due to weak demand but also Thailand's tight restrictions, which included 14-day hotel quarantine requirements, COVID-19 tests and health insurance coverage of up to $US100,000 ($A132,875)
From November 1, vaccinated visitors from eligible countries including the United Kingdom, the United States, Germany, France, Australia, China, Japan and Singapore will be allowed to skip quarantine, providing they have negative COVID-19 tests.
Australian Associated Press