Jang et al J Clin Med Res • 2011;3(4):199-202 Table 1. Comparative Observation of Seasonal and Region Outbreaks Between Human Brucellosis and Leptospirosis in Korea, 2001-2010 Item Season Spring Summer Autumn Winter Total Region Eastern Western Central Jeju-Island Total Brucellosis Leptospirosis Cases (%) 170 (26.1) ** 207 (31.8) ** 156 (24.0) 118 (18.1) ** 651 256 (39.3) 321 (49.3) ** 67 (10.3) ** 7 (1.1) 651 95% CI 22.2-29.5 28.2-35.4 20.7-27.3 15.1-21.1 35.1-43.1 45.5-53.1 8.0-12.6 0.3-1.9 Cases (%) 32 (2.8) 80 (6.9) 940 (84.5) ** 101 (8.8) 1,153 775 (67.2) ** 325 (28.2) 51 (4.4) 2 (0.2) 1,153 95% CI 1.9-3.8 5.4-8.4 79.3-83.7 7.2-10.4 64.5-69.9 25.6-30.8 3.2-5.6 - Average prevalence rate per 100,000 populations from 2001 to 2010. Chi-square analysis indicated a signiﬁcant difference from the total value. *p < 0.05, **p < 0.01. (KCDCP) [7]. To better quantify the impact of HB and HL on health in Korea, we compiled and analyzed information of the cases and rate of prevalence, and related risk factors including frequency distribution of seasonal outbreaks, gen- der, age, and occupation of the patients. The statistical meth- ods of data analysis included one-way analysis of variance (ANOVA) of the prevalence rate per 100,000 populations between HB and HL. Chi-square test (X2-test) was also used to compare frequency rate of the risk factors of the disease between the HB and HL. The analysis was preformed using statistical analysis software by the Microsoft Excel. Result was considered to be statistically signiﬁcant at p < 0.05 and p < 0.01. Results and Discussion Table 1 shows the prevalence of HB and HL in Korea from 2001 to 2010. A total 651 cases of HB occurred in Korea, and the average prevalence rate per 100,000 populations was 0.15. There are eight species of Brucella that are currently recognized based on antigen variation and host speciﬁcity. Among those species, Brucella melitensis and B. suis are the most pathogenic strains for humans. B. abortus is less virulent, but it nevertheless causes serious social-economic losses in endemic areas through human exposure to about calves [5]. Increasing cases of brucellosis in cattle have oc- curred in Korea with the large-scale introduction of under- screened Korean native cattle and the herd test that has been conducted since 2004. As the screening test was reinforced, the number of infected cattle has increased from 1,088 heads in 2003 to 5,380 heads in 2004, and to 26,454 heads in 2006 [8]. Accordingly, the number of HB has also sharply in- creased from 1 case in 2002 to 215 cases in 2006. A total of 651 cases were reported from 2002 to 2010 [5, 7]. During the same period in HL, the prevalence rate was 0.24 per 100,000 populations with a variation of 0.17 to 0.43. The prevalence rate in HL was much higher than that of HB. This signiﬁcant difference between HB and HL can be explained on the basis of the difference in their epidemic pattern. The distribution of HB and HL throughout the year re- vealed that outbreaks in spring to summer (26.1% and 31.8% of total cases) were more frequent in HB than HL (2.8% and 6.9%) (p < 0.01), and HB occurred all year round, although monthly changes in the number of cases occurred. In the case of HL, however, the outbreaks in autumn (84.5% of total cases) was much higher than that of HB (24.0%) (p < 0.01). These data strongly indicate that the incidence is inﬂuenced by their peculiar climate, geographical and environmental condition of the epidemiological pattern and aspects [2, 3, 6]. Geographical distribution of HB cases was eastern and western regions of the rural (88.6% of total) in Korean penin- sula, showed higher outbreaks than the other area, while HL was occurred in easterly regions (67.2%). As shown Table 2, a signiﬁcantly more males infected in both HB (86.8%) and HL (59.5%) than those of females in both HB (15.2%) and HL (40.5%), respectively (p < 0.01). These remarkable differences in gender distribution are believed to differences between male and female in terms of works and hosts activi- ties [3, 6]. The percentage distribution of HB and HL cases by age group was as follows: in cases of HB, age groups of under 19, 20-39, 40-59 and over 60 years old the percentage were 0.5%, 13.5%, 62.1% and 23.8%, respectively, while in that of HL cases were 1.2%, 10.3%, 28.9% and 59.6%, re- spectively. However, the distribution by age groups was dif- ferent between HB and HL, while the incidences over 62.1% 200 Articles © The authors | Journal compilation © J Clin Med Res and Elmer Press™ | www.jocmr.org