Public Health Implication of Emerging Zoonoses; Epidemiological Aspects of Human Brucellosis and Leptospirosis in Korea

Park, Sang Hee; Kim, Jin Seok; Lee, Myong Jin; Che, Nong Hun; Bang, Hyung Ae; Rhim, Kook Hwan; Lee, Won Chang

Abstract

BACKGROUND
In recent years in Korea, human brucellosis (HB) and human leptospirosis (HL) have become the major zoonoses with a dramatic increased cases of incidence in man; we analyzed the current state and epidemiological aspects of related risk factors from 2001 to 2008. METHODS: Based on the surveillance data of HB and HL, most are confirmed cases in Korea from the Annual Reports of HB and HL in the Disease Web Statistics System, Korea Center for Disease Control and Prevention (KCDCP). RESULTS: The incidence of HB in Korea from 2001 to 2008 was 596 cases, and that of HL was 1,025 cases. When both prevalence rates were compared during the same period, the HB was lower than that of HL. The seasonal distribution of HB cases showed that the incidence from spring to summer were higher than that of HL (P<0.01), while the outbreaks of HL in autumn was much more than that of HB (P<0.01). Geographical distribution HB cases were western and central regions of the rural (60.4% of total) in the Korean peninsula, showing higher outbreaks than other areas, while HL occurred in easterly regions (72.7%). Significantly more males were infected in both HB (84.2%) and HL (58.9%) than those of females in both HB (13.1%) and HL (41.1%), respectively (P<0.01). The distribution by age groups were different between HB and HL, while the outbreaks over 62.8% of the cases of HB occurred in 40 to 59 year-old age group, and that of HL was clearly showing a high incidence in the elderly age over-60-year-old (60.8%) (P<0.01). In both diseases, elderly people especially in farmers showed a very high prevalence rate (62.8% of HB and 60.8% of HL), which is possibly due to increased outdoor activities and a decreased number of young people in those areas. The occupational distribution of HB cases were farmers, veterinarians, dairyman and others, and those of HL cases were broad. CONCLUSION: The difference in HB and HL risk factors reflects the different influences of hosts/vector, climate, and geographical and environmental characteristics in the epidemiological patterns.