Iinfluenza and ARI intensity in Bulgaria was low during week No 43 (21.10.2013 - 27.10.2013) and the total incidence per 10,000 population was 58.86 (during week No 42 the incidence was 63.63). From a total of 381 562 persons under surveillance, belonging to all age groups, a total of 2 246 ARI cases have been reported (during week No 42 the cases were 2 428). The incidence was highest in the age group 0-4 yrs (268.77 per 10,000 population), followed by age group of 5-14 yrs (168.26 per 10,000).