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2. A health emergency has been declared. Тerviseamet. 11.08.2021 URL: https://www.terviseamet.ee/ru/novosti/v-sfere-zdravoohraneniya-obyavlena-chrezvychaynaya-situaciya
3. Paraskevis D., Yavropoulou M., Tsiodras S. Burden of COVID-19 in Different Countries. MDPI. 31.12.2021. URL: https://www.mdpi.com/topics/covid_burden.
4. 14.9 million excess deaths associated with the COVID-19 pandemic in 2020 and 2021. WHO. 05.05.2022. URL: https://www.who.int/news/item/05-05-2022-14.9-million-excess-deaths-were-associated-with-the-covid-19-pandemic-in-2020-and-2021.
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