“The WHO has warned that the virus that causes the disease COVID-19 has changed since the first reports about it and it continues to change.

Thus, four options of concern have emerged, and even more will appear while the virus continues to spread, ”TASS quoted Gebreyesus as saying at a briefing in Geneva.

According to him, the increase in the incidence recorded in recent weeks is due to the delta strain.

Earlier, the number of countries and territories where the highly contagious strain of the delta coronavirus circulates increased from 20 to 27 July by eight and reached 132.