Participation is granted only for people who fulfill the 2G rules.
What is the 2G rule?!
In German Language: Geimpft (vaccinated) and/or Genesen (recovered). So, all participants have to be vaccinated and/or recovered. These rules were implemented by Austria Federal Ministry of Health.
At the hotel check-in and the conference registration desk, you are required to show the official proof of document.
Actual entry conditions to Austria can be found and followed at the Official Government Website below: