西伯利亚一家瘟疫研究所的一名实验室工作人员在不明情况下发病并死亡，促使当局隔离了数十人，俄罗斯卫生监督机构负责人也飞往伊尔库茨克地区。
A laboratory worker at a plague research institute in Siberia has fallen ill and died in undisclosed circumstances, prompting authorities to quarantine dozens of people, and the head of Russia's health watchdog to fly to the Irkutsk region.