During the week No 50 (13.12.2021 - 19.12.2021) ARI and influenza intensity in Bulgaria did not  increase compared to the previous week No 49 (06.12.2021 - 12.12.2021). The total incidence per 10,000 population was 85.86 (during week No 49 the incidence was 89.07). From a total of 379 796 persons under surveillance, belonging to all age groups, a total of 3 379 ARI cases have been reported (during week No 49 the cases were 3 383). The incidence was highest in the age group 0-4 yrs (401.21 per 10,000 population), followed by age group of 5-14 yrs (262.65 per 10,000 population).During this week one positive specimen for influenza virus type A/H3N2  was reported from the national Flu Lab (NCIPD).