Bulgaria should not exceed the critical daily threshold of 1,500 new Covid-19 infections, explained mathematician Nikolay Vitanov from the Bulgarian Academy of Sciences in an interview for BNT. In his view, 20% of the Bulgarian citizens have gone through Covid-19 until now. We can start talking about herd immunity when the number of people infected with the novel coronavirus reaches 800,000 or 900,000, said Professor Vitanov and added that Bulgaria was still far from herd immunity. 

In his words, there is hidden morbidity in Bulgaria and 3 out of every 200 people are positive for Covid-19. Students from the 8^th to 12^th grade are the most problematic group, because they do not observe the anti-epidemic measures. That is why morbidity in this group is 60% higher than normal, clarified Nikolay Vitanov.