The guidelines are prepared in accordance with the latest version of the document developed by the European Union Aviation Safety Agency (EASA) and European Centre for Disease Prevention and Control (ECDC). Following of general prevention measures is of key importance.  

Recommended measures shall be regularly assessed and updated in accordance with changes of knowledge about risk of transmission, as well as in accordance with development of other diagnostic or preventive measures. 

Link to the document:
https://s3.eu-central-1.amazonaws.com/web.repository/ijzcg-media/files/1...
 
EASA COVID-19 Aviation Health Safety Protocol (v.3), that used as basis for this document, is available at the link:
https://www.easa.europa.eu/document-library/general-publications/covid-1...

Other EASA documents related to Covid-19 can be found at the following link:
https://www.easa.europa.eu/the-agency/coronavirus-covid-19

The Civil Aviation Agency developed separate page for information regarding the COVID-19 measures and procedures:
https://caa.me/me/covid-19