PRAGUE—Czech Prime Minster Andrej Babis fired his health minister on Wednesday, the third to have been ousted during the pandemic in one of Europe’s hardest-hit countries. Jan Blatny was replaced by Petr Arenberger, the director of Prague’s University Hospital Vinohrady, who was sworn in by President Milos Zeman. The move opens the way for a possible use of Russian and Chinese vaccines, which have not been approved by the European Union’s drug regulator. Babis repeatedly criticized Blatny over his handling of the pandemic, including imposing strict conditions for the use of experimental drugs to treat COVID-19 patients. Blatny was also under fire from Zeman, an ally of Babis who is known for his pro-Russian and pro-Chinese views. Zeman asked the prime minister last month to replace Blatny over his refusal to allow the use of Russia’s Sputnik V vaccine because it has not been approved by the European Medicines Agency, …