It was stated that tens of thousands of international flights were canceled over the Christmas holiday due to the Omicron mutation. It was stated that the Omicron variant caused a shortage of personnel, which led to the cancellation of many international flights that took place during the Christmas holiday. Domestic and international flights to the United States were most affected by this situation.
According to the statements made by international flight companies, it was announced that there were cancellations and delays in flights due to the fact that many employees had to take tests and the pilots were also infected with the virus.
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https://www.cumhuriyet.com.tr/dunya/omicron-sebebiyle-on-binlenen-ucus-iptal-edildi-1895386