Impact of measures to control brucellosis on disease characteristics in humans: experience from an endemic region in the Balkans.

Aim: To analyze the impact of measures undertaken to control brucellosis in the Republic of Macedonia on demographic, epidemiological and clinical characteristics of the disease in humans.

Methods: Demographic, epidemiological and clinical characteristics of 340 patients with brucellosis were retrospectively analyzed. Patients were treated at the University Clinic of Infectious Diseases in Skopje during three time periods: 1989-1990 when no national strategy for disease control existed, 2000-2001 when some activities for control were performed and 2011-2014 when an organized and financially supported strategy was accomplished.

Results: A drastic decrease of the number of cases of human brucellosis during the last period when compared to the first two ones (3.9 and 3.3 times lower, respectively) was evident. Patients from the third period were significantly older, with median age 41 years (range 4-73) vs. 31 years (3-77) and 34 years (1-74), respectively (p = .013). There were more males (86.6 vs. 73.6% and 63.2%, respectively, p = .002) and the disease was more often acquired professionally (80.6 vs. 60.1% and 59.2%, respectively, p = .006). Fewer patients from the third period had elevated body temperature either as a symptom (50.7 vs. 73.6% and 69.6%, respectively, p = .003), or as a sign (35.8 vs. 55.4% and 56.8%, respectively, p = .011) and less often exhibited focal forms (40.3 vs. 56.8% and 64.0%, respectively, p = .007).

Conclusion: The national strategy for brucellosis control, which included vaccination of small ruminants, resulted in a decrease of human brucellosis cases in the Republic of Macedonia and there was a tendency to milder disease manifestations.