Students stand on the roof of a wooden boat as haze blankets the Musi River while they travel to school in Palembang, on Indonesia's Sumatra island, September 10, 2015. Indonesia is investigating 10 firms over worsening forest fires that have created a blanket of smog over Southeast Asia, threatening them with sanctions if they are found responsible, a government minister said on Tuesday. The thick haze from Indonesia's Sumatra and Kalimantan islands has forced the repeated cancellation of flights in the area and pushed air quality to unhealthy levels in neighbouring Singapore and Malaysia. (Photo by Reuters/Beawiharta)

In this photograph taken on February 15, 2021, doctor Sergen Saracoglu (L) and nurse Yilzdiz Ayten (C) from the Bahcesaray public hospital vaccination team, arrive at the village of Guneyyamac in eastern Turkey, as part of an expedition to vaccinate residents of 65 years old or above with Sinovac's CoronaVac Covid-19 vaccine. (Photo by Bulent Kilic/AFP Photo)