Epidemiological Aspects and Trends of the Extensive Eradication Programs for Bovine Brucellosis Outbreaks-Associated Human

(1)

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Epidemiological Aspects and Trends of the Extensive Eradication Programs for Bovine Brucellosis Outbreaks-Associated Human

Brucellosis in Korea, 2002~2013

Won-Chang Lee, Ph.D.¹, Hachung Yoon, Ph.D.², Myeong-Jin Lee, Ph.D.³, Young Hwan Kwon, M.D.⁴

1College of Veterinary Medicine, Konkuk University, Seoul, ²Department of Veterinary Epidemiology in Animal and Plant Quarantine Agency, Gimcheon, Korea, ³Public Health in Faculty of Health and Nutrition, Otemae University, Osaka, Japan, ⁴Department of Internal

Medicine, Aeromedical Center, Korean Air, Seoul, Korea

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Received: July 30, 2019, Accepted: August 6, 2019

Correspondence: Young Hwan Kwon, Aeromedical Center, Korean Air, 260, Haneul-gil, Gangseo-ru, Seoul, 07505, Korea Tel: 82-2-2656-7150, Fax: 82-2-2656-8858 E-mail: [email protected]

I. INTRODUCTION

Brucellosis, also known as “undulant fever”, “Mediterranean fever” or “Malta fever” is a zoonosis caused by the Brucella species and the infection is almost invariably transmitted by direct or indirect contact with infected animals or their products. It affects people of all age groups and both sexes worldwide [1,2]. Over the last decade, brucellosis has become a principal zoonosis with a dramatic increase in incidence in domestic cattle and man in Korea [3,4]. In addition, a monitoring and surveillance system for bovine brucellosis (BB) based on a test-and-slaughter policy was established in the

1960s and has been in operation for more than 60 years following the official case in Korea in 1956 [4,5]. According to the Act on the Prevention of Contagious Animal Diseases, Brucellosis is a Class 2 notifiable animal disease and is currently regulated by the standard operation procedure (SOP) for tuberculosis and brucellosis implemented by the Ministry of Agriculture, Food, and Rural Affairs (MAFRA) [6].

Notwithstanding, human brucellosis (HB) was classified as a type 3 notifiable disease by the Communicable Disease Prevention Act in 2000, for its zoonotic effects [7]. Thereafter, human brucellosis was reported in an official reported case in 2002 [3,4,7]. Prior to 2000, before the implementation of the BB control program in Korea and the stamp-out approach to strictly quarantine infected herds, brucellosis outbreaks have continued to increase among Korean native beef cattle that were neglected in the BB control programs prior to 2004 [3,4,8,9]. Accordingly, the screening tests for brucellosis have been reinforced; moreover, the number of HB cases has sharply increased after the first report from one case in 2002 to 215

(2)

׊׷׾ױ׶׭֨׊׺׽׫׭״״׷׻ױ׻֨ח׽׼ת׺׭ש׳׻ֵ׉׻׻׷׫ױש׼׭׬֨א׽׵ש׶֨׊׺׽׫׭״״׷׻ױ׻

΅ΒΓΝΖ͑͑͢͟ʹΠΞΡΒΣΒΥΚΧΖ͑ΠΓΤΖΣΧΒΥΚΠΟ͑ΠΟ͑ΥΙΖ͑ΚΟΔΚΕΖΟΔΖ͑ΚΟΕΖΩ͑ΠΗ͑ΥΙΖ ΓΣΦΔΖΝΝΠΤΚΤ͑ ΠΦΥΓΣΖΒΜΤ͑ ΒΞΠΟΘ͑ ΕΠΞΖΤΥΚΔ͑ ΔΒΥΥΝΖ͑ ΒΟΕ͑ ΙΦΞΒΟΤ͑ ΚΟ͑

ͼΠΣΖΒ͑ͣͣ͝͡͡ίͣͤ͢͡

ͺΥΖΞ ͳΠΧΚΟΖ͑ΓΣΦΔΖΝΝΠΤΚΤ ͹ΦΞΒΟ͑ΓΣΦΔΖΝΝΠΤΚΤ

ͿΠ͑͟ΠΗ͑ΔΒΤΖΤ ͩͪͣͥ͝͡ ͨͤ͡

ʹͺ΃͢͠͡͡͝͡͡͡^͚͢ ͑͑͑ͧͩ͢͢͟ ͑͑ ͣ͟͢͡

ʹΠΣΣΖΝΒΥΚΠΟ͑ΔΠΖΗΗΚΔΚΖΟΥ^͚ͣ ＋ͪͩͦ͛͟͡

ͲΥΥΒΔΜ͑ΣΒΥΚΠ͢͠͝͡͡͡^͚ͤ ͑͑ͨͩͩ͟

͚͢ʹΦΞΦΝΒΥΚΧΖ͑ΚΟΔΚΕΖΟΔΖ͑ΣΒΥΖ͑ΡΖΣ͑͑͢͟͡͡͝͡͡͡^͚ͣʹΠΣΣΖΝΒΥΚΠΟ͑ΔΠΖΗΗΚΔΚΖΟΥ͑

ΓΖΥΨΖΖΟ͑ ΓΠΧΚΟΖ͑ ΒΟΕ͑ ΙΦΞΒΟ͑ ΓΣΦΔΖΝΝΠΤΚΤ͑͟^͚ͤ΅ΙΖ͑ ΣΒΥΚΠ͑ ΠΗ͑ ΙΦΞΒΟ͑

ΓΣΦΔΖΝΝΠΤΚΤ͑ΔΒΤΖΤ͑ΥΣΒΟΤΞΚΥΥΖΕ͑ΗΣΠΞ͑ΓΠΧΚΟΖ͑ΓΣΦΔΖΝΝΠΤΚΤ͑ΔΒΤΖΤ͑ΡΖΣ͑

͑͢͝͡͡͡ΔΒΥΥΝΖ͑͟΄ΥΒΥΚΤΥΚΔΒΝΝΪ͑ΤΚΘΟΚΗΚΔΒΟΥ͑ΝΖΧΖΝΤ͑ΨΖΣΖ͑ΤΖΥ͑ΒΥ͑͛΁ͭ͟͢͟͡͡ ͷΚΘ͑͑͟͢͟΅ΣΖΟΕΤ͑ΠΗ͑ΓΣΦΔΖΝΝΠΤΚΤ͑ΠΦΥΓΣΖΒΜΤ͑ΒΞΠΟΘ͑ΕΠΞΖΤΥΚΔ͑ΔΒΥΥΝΖ͑ΒΟΕ ΙΦΞΒΟΤ͑ΚΟ͑ͼΠΣΖΒ͑ͣͣ͝͡͡ίͣͤ͢͟͡

cases in 2006, when it was at its peak, and tended to decrease thereafter. However, there are still outbreaks in Korea [2,4,7].

In the present study, we focus on the epidemiological trends of the extensive eradication programs for brucellosis outbreaks and control (EEPBOC) in Korea with a focus on incidence from 2002 through 2013, and the brucellosis epidemic-control strategies that have made brucellosis a persistent public health problem in Korea.

II. MATERIALS AND METHODS ՇՄԶ՚շ֊շԶջ֎֊ֈշչ֊տօք

There were 89,240 cases of BB positive reactors in domestic cattle (dairy and native cattle and others) between 2002 and 2013. For this, we used the raw data from the webpage of the Korea Animal Health Integrated System (KAHIS) operated by the Animal and Plant Quarantine Agency (QIA) that provides information about notifiable animal disease [6]. Statistics for a total of 703 HB cases were obtained from the Disease Web Statistics System by the Korea Center for Disease Control and prevention (KCDC), 2002-2013 [7].

ՈՄԶթ֊շ֊տ։֊տչշւԶշքշւ֏։տ։

In this study, the incidence rate (IR) of brucellosis among cattle and man per 100,000 were calculated; we then calculated the attack ratio (AR, the ratio of HB cases transmitted from BB cases per 1,000 cattle, which was calculated by the number of HB cases divided by the number of BB cases×1,000) [3].

Statistically significant differences between the epidemiological aspects were determined using the X²-test or paired t-test and

estimating 95% confidence intervals (CI), and the Pearson’s correlation coefficient (r) of brucellosis outbreaks between cattle and human cases; the levels of significance for P-values less than 0.05. Data analysis was carried out using the statistical system software, Microsoft Excel 2007.

III. RESULTS

There were a total of 89,240 BB reactors among domestic cattle outbreaks and a total of 703 cases of HB in Korea between 2002 and 2013, as shown in Table 1 and Fig. 1. The CIR of BB cases in domestic cattle was 611.8 per 100,000 cattle from 2002 to 2013, and that of HB cases was 0.12 per 100,000 persons. The number and CIR of brucellosis cases in both the BB and HB levels tended to increase after 2003, peaked in 2006, and tended to decrease thereafter. However, there are still outbreaks in Korea. Moreover, the correlation coefficient of brucellosis outbreaks between cattle and humans was highly significant (r=Ƅ0.985, Pƕ0.01) (Fig. 1). In addition the AR of HB was 7.88 per 1,000 cattle. Table 2 shows the epidemic aspects such as season and geotropism for outbreaks of brucellosis among cattle and man. BB occurred most frequently among cattle in spring (31.0% of the total cases), and among infected humans assisting in calf delivery or livestock products workers in early summer (30.2%). On the other hand, the BB and HB cases were geographically localized in the southeastern region of the Korean peninsula (40.7% of the total BB cases and 43.2% of HB) as compared to other areas (Pƕ0.01).

(3)

ן׷׶ֵ׋װש׶ׯ֨ה׭׭ִ֨׭׼֨ש״ֶ

΅ΒΓΝΖ͑ ͣ͑͟ ʹΠΞΡΒΣΒΥΚΧΖ͑ ΠΓΤΖΣΧΒΥΚΠΟ͑ ΠΟ͑ ΥΙΖ͑ ΖΡΚΕΖΞΚΔ͑ ΒΤΡΖΔΥΤ͑ ΠΗ͑ ΓΣΦΔΖΝΝΠΤΚΤ͑ ΠΦΥΓΣΖΒΜΤ͑ ΒΞΠΟΘ͑ ΕΠΞΖΤΥΚΔ͑ ΔΒΥΥΝΖ͑ ΒΟΕ͑ ΙΦΞΒΟΤ͑ ΚΟ͑ ͼΠΣΖΒ͑͝

ͣͣ͡͡ίͣͤ͑͢͡

͑ͺΥΖΞ ͳΠΧΚΟΖ͑ͳΣΦΔΖΝΝΠΤΚΤ ͹ΦΞΒΟ͑ͳΣΦΔΖΝΝΠΤΚΤ

ʹΒΤΖΤ ͖͙͖͑ͪͦ͑ʹͺ͚ ʹΒΤΖΤ ͖͙͖͑ͪͦ͑ʹͺ͚

΄ΖΒΤΠΟ

͑͑΄ΡΣΚΟΘ ͣͨͧͤͦ͝ ͙ͤ͑ͤͧ͢͟͟͡͡ί͚ͤͤ͢͟ ͪͣ͢ ͙ͣͨͤ͑ͣͥ͟͟͡ί͚ͤͧ͟͡

͑͑΄ΦΞΞΖΣ ͣͤͩͪ͢͝ ͙ͣͧͨ͑ͣͧͤ͟͟ί͚ͣͧͧ͟ ͣͣ͢ ͙ͤͣ͑ͣͧ͟͟͢͡ί͚ͤͥͤ͟

͑͑ͲΦΥΦΞΟ ͪͥͪ͢͢͝ ͙ͣͩ͑ͤͦ͢͟͢͟ί͚ͣͣ͟͢ ͩ͢͡ ͙ͣͦͧ͑ͣͨ͟͢͟ί͚ͣͪͦ͟

͑͑ΈΚΟΥΖΣ ͩͣͪͦ͢͝ ͙ͣͪ͑ͣͧ͟͟͡͡ί͚ͣͣ͢͟ ͪ͢͢ ͙ͧͪ͑ͤͨ͢͟͢͟ί͚ͣ͟͢͡

͑͑΅ΠΥΒΝ ͩͪͣͥ͝͡ ͨͤ͡

͑͑΁͞ΧΒΝΦΖ ＜͛͟͢͡͡ ＜͛͟͢͡͡

͸ΖΠΘΣΒΡΙΚΔΒΝ͑ΣΖΘΚΠΟ

͑͑ͿΠΣΥΙΖΒΤΥΖΣΟ ͑ͤͪͥͦ͝ ͙͑ͥͥ͑ͥͤ͟͟ί͚ͥͦ͟ ͑ͥ͡ ͙͑ͦͨ͑ͥ͟͟͡ί͚ͨͥ͟

͑͑ͿΠΣΥΙΨΖΤΥΖΣΟ ͑ͦͦͪͪ͝ ͙͑ͧͤ͑ͧ͟͟͢ί͚ͧͦ͟ ͑ͦͨ ͙͑ͩ͑ͧ͟͢͟͡ί͚͢͟͢͡

͑͑ʹΖΟΥΣΒΝ ͣͣͪͥͨ͝ ͙ͣͦͨ͑ͣͦͥ͟͟ί͚ͣͧ͟͡ ͧ͢͢ ͙ͣͣͪ͑ͪͩ͟͢͟ί͚ͣͧ͟͡

͑͑΄ΠΦΥΙΖΒΤΥΖΣΟ ͤͧͣͪ͢͝ ͙ͥͨ͑ͥͤ͟͟͡͡ί͚ͥ͢͟͢ ͤͥ͡ ͙ͥͤͣ͑ͤͩͩ͟͟ί͚ͥͨͧ͟

͑͑΄ΠΦΥΙΨΖΤΥΖΣΟ ͣͥͣͥ͡͝ ͙ͣͣͪ͑ͣͣͧ͟͟ί͚ͣͤͣ͟ ͥ͢͢ ͙ͣ͑ͨ͟͢͢͟͢͡ί͚ͣͤ͟͢

͑͑΅ΠΥΒΝ ͩͪͣͥ͝͡ ͨͤ͡

͑΁͞ΧΒΝΦΖ ＜͛͟͢͡͡ ＜͛͟͢͡͡

΄ΥΒΥΚΤΥΚΔΒΝΝΪ͑ΤΚΘΟΚΗΚΔΒΟΥ͑ΝΖΧΖΝΤ͑ΨΖΣΖ͑ΤΖΥ͑ΒΥ͑͛΁＜͟͢͟͡͡

As shown in Table 3, risk factors and attack ratio outbreaks-associated HB in Korea between 2002 and 2013 were analyzed by association with gender, age, inhabitant, occupation, and AR of the individual. A significantly higher number of men were infected (86.3% of the total cases) than women (13.7%), (Pƕ0.01). The percentage distribution of HB among those aged less than 39 years and among those aged more than 40 years was 14.1% and 85.9%, respectively, (Pƕ0.01).

The distribution of HB cases was significantly higher in rural areas (91.2% of the total cases) than in urban areas (8.8%), (Pƕ0.01). In addition, the distribution of cases classified by occupation was as follows: farming and related workers (40.7%

of the total cases) and other various jobs (59.3%), respectively, (Pƕ0.01).

On the other hand, the AR of HB cases studied with respect to gender, age, inhabitant, and occupational characteristics of the individual. Significantly more men (6.8 per 1,000 BB cases) than women (1.08) were attacked (Pƕ0.01); moreover, this was true for those aged more than 40 years (4.89), (Pƕ0.01) and for rural inhabitants (7.18), (Pƕ0.01). Farmers and related workers were more likely to be attacked by brucellosis (3.21), (Pƕ0.01).

IV. DISCUSSION

Brucellosis is a zoonotic disease; hence the ultimate sources

of infection are infected animals and the key species are the major food-producing animals [1]. The possibility of human beings falling ill with brucellosis has been a reality for a long time in Korea because BB has been continuously reported on for many decades. After 1990, the number of cases of BB has increased to above 400 every year [3,4,8,10]. Notwithstanding the extensive eradication programs for brucellosis outbreaks and control (EEPBOC), the national implementation of the test-and slaughter policy, and the stamp-out approach to strictly quarantine infected herd, brucellosis outbreaks have continued to increase among Korean native cattle, including beef cattle that were neglected in the EEPBOC prior to 2004 [3-6].

Accordingly, the screen tests for brucellosis have been reinforced; moreover, the number of HB cases has sharply increased after the first report in 2002 from 16 cases in 2003 to 215 cases in 2006, when it was at its peak and thereafter, tended to be decreased. However, there are still outbreaks in Korea [2,4,7].

A total of 703 cases or a CIR of 0.12 per 100,000 population of HB was reported between 2002 and 2013. Therefore, trends of BB outbreaks-associated HB cases were similar, and a very high positive correlation coefficient of Ƅ0.985 (Pƕ0.01) was observed (Fig.1). In addition, brucellosis in human and cattle was caused by Brucella abortus infections and the human isolates were clustered together with the animal isolates; a significant genetic correlation with regional distribution was observed [4,8]. One may explain that the HB cases in Korea were related

(4)

׊׷׾ױ׶׭֨׊׺׽׫׭״״׷׻ױ׻֨ח׽׼ת׺׭ש׳׻ֵ׉׻׻׷׫ױש׼׭׬֨א׽׵ש׶֨׊׺׽׫׭״״׷׻ױ׻

΅ΒΓΝΖ͑ͤ͑͟ʹΠΞΡΒΣΒΥΚΧΖ͑ΠΓΤΖΣΧΒΥΚΠΟ͑ΠΟ͑ΥΙΖ͑ΖΡΚΕΖΞΚΔ͑ΣΚΤΜ͑ΗΒΔΥΠΣΤ͑ΠΗ ΙΦΞΒΟ͑ΓΣΦΔΖΝΝΠΤΚΤ͑ΚΟ͑ͼΠΣΖΒ͑ͣͣ͝͡͡ίͣͤ͢͡

ͺΥΖΞ ͹ΦΞΒΟ͑ΓΣΦΔΖΝΝΠΤΚΤ

ʹΒΤΖΤ ͖͙͖͑ͪͦ͑ʹͺ͚ ͲΥΥΒΔΜ͑ΣΒΥΚΠ

΅ΠΥΒΝ͑ΒΥΥΒΔΜ͑ΣΒΥΚΠ ͨͤ͡ ͨͩͩ͟

͸ΖΟΕΖΣ

͑͑;ΒΝΖ ͧͨ͡ ͙ͩͧͤ͑ͨͨͦ͟͟ί͚ͪͦͣ͟ ͧͩ͟͡

͑͑ͷΖΞΒΝΖ ͪͧ ͙ͤͨ͑ͣ͢͟͢͢͟ί͚ͧͣ͢͟ ͩ͢͟͡

͑͑΅ΠΥΒΝ ͨͤ͡ ͨͩͩ͟

͑͑΁͞ΧΒΝΦΖ ＜͛͟͢͡͡ ＜͛͟͢͡͡

ͲΘΖ

͑͑＜ͪ͢ ͨ ͙͑͑ͤ͢͟͟͡͡ί͚ͨ͢͟ ͩ͟͡͡

͑͑ͣ͡ίͤͪ ͪͣ ͙ͤ͑ͧ͢͟͢͢͟͡ί͚ͦͧ͢͟ ͤ͢͟͡

͑͑ͥ͡ίͦͪ ͥͤͧ ͙ͧͣ͑ͦͩͥ͟͟͡ί͚ͧͦͧ͟ ͥͩͪ͟

͑͑＞ͧ͡ ͧͩ͢ ͙ͣͤͪ͑ͣͨ͟͟͡ί͚ͣͨ͟͢ ͩͩ͢͟

͑͑΁͞ΧΒΝΦΖ ＜͛͟͢͡͡ ＜͛͟͢͡͡

ͺΟΙΒΓΚΥΒΟΥ

͑͑ΆΣΓΒΟ ͧͣ ͙͑ͩͩ͑ͧͨ͟͟ί͚ͪ͢͟͡ ͨ͟͡͡

͑͑΃ΦΣΒΝ ͧͥ͢ ͙ͪͣ͑ͩͪ͢͟͟͢ί͚ͪͤͤ͟ ͨͩ͟͢

͑͑΅ΠΥΒΝ ͨͤ͡ ͑ ͨͩͩ͟

͑͑΁͞ΧΒΝΦΖ ＜͛͟͢͡͡ ＜͛͟͢͡͡

΀ΔΔΦΡΒΥΚΠΟ

͑͑ΈΙΚΥΖ͞ΔΠΝΝΒΣ͑ΛΠΓΤ ͤ͢ ͙͑ͩ͑ͩ͢͟͟͡ί͚ͣͩ͟ ͦ͟͢͡

͑͑ͳΝΦΖ͞ΔΠΝΝΒΣ͑ΛΠΓΤ ͪ͢ ͙͑ͣͨ͑ͦ͟͢͟ί͚ͤͪ͟ ͣ͟͢͡

͑͑΄ΡΖΔΚΒΝΚΤΥΤ ͣͪ ͙͑ͥ͑ͣͧ͟͢͟ί͚ͦͧ͟ ͤͣ͟͡

͑͑ͷΒΣΞΖΣ͑͗͑ΗΚΤΙΖΣΪ ͣͩͧ ͙ͥͨ͑ͤͨ͟͟͢͡ί͚ͥͥͤ͟ ͤͣ͟͢

͑͑;ΚΤΥΣΖΤΤΖΤ ͤ͢ ͙͑ͩ͑ͧ͢͟͟͡ί͚ͤ͟͡ ͦ͟͢͡

͑͑΄ΥΦΕΖΟΥΤ ͧ ͙͑ͪ͑ͣ͟͟͡͡ί͚ͧ͢͟ ͨ͟͡͡

͑͑ΆΟΖΞΡΝΠΪΖΕ ͢͢ ͙͑ͧ͑ͨ͢͟͟͡ί͚ͣͦ͟ ͣ͟͢͡

͑͑΀ΥΙΖΣ͑ΛΠΓΤ ͤͣͧ ͥͧͧ͟ ͤͧͦ͟

͑͑΁͞ΧΒΝΦΖ ＜͛͟͢͡͡ ＜͛͟͢͡͡

΅ΙΖ͑ ΒΥΥΒΔΜ͑ ΣΒΥΚΠ͑ ΠΗ͑ ΙΦΞΒΟ͑ ΓΣΦΔΖΝΝΠΤΚΤ͑ ΥΣΒΟΤΞΚΥΥΖΕ͑ ΗΣΠΞ͑ ΓΠΧΚΟΖ͑

ΓΣΦΔΖΝΝΠΤΚΤ͑ΔΒΤΖΤ͑ΡΖΣ͑͑͢͝͡͡͡ΔΒΥΥΝΖ͑͟΀ΥΙΖΣ͑ΗΠΠΥΟΠΥΖΤ͑ΒΣΖ͑ΚΟ͑΅ΒΓΝΖ͑ͣ͟

to contact with infected cattle during animal-associated activities such as calving or artificial insemination for the livestock [3,4,10-13].

The seasonal distribution of the highest HB incidence from the end of April to the beginning of September in Korea is explained by the lactation or parturition period in domestic cattle. These data influenced by climate and the seasonal characteristics of brucellosis occurrence in Korea are actually transforming due to climate change [1,3,4,8,14,15].

On the other hand, the BB and HB cases were geographically localized in the southeastern region of the Korean peninsula as compared to other areas, and the related risk of brucellosis outbreaks cases by regions between cattle and human was significantly higher.

The epidemiological risk factors and the AR of HB cases that occurred in Korea between 2002 and 2013 were analyzed; a significant higher number of men were infected than women;

this is believed to be due to the different responsibilities that men and women have in their jobs and the various activities that are characteristics in the livestock field [1,3,7]. The percentage distribution of HB among those aged less than 39 years and among those aged more than 40 years was 14.1%

and 85.9%, respectively. Thus, the higher incidence of HB in the elderly group of farmers may be a result of the increased risk of infection because of the indoor or outdoor activities required for livestock work in rural areas, which are prone to BB outbreaks. In Korea, there is a tendency for most young people to move to cities for work, whereas, the elderly people work as farmers and livestock workers on their own land [3-5,8,9].

On the other hand, the distribution of HB cases was significantly higher in rural areas than in urban areas. In addition, the distribution of cases classified by occupation was as follows: farming and related worker, blue-collar jobs, white-collar jobs, mistresses, and other various jobs, respectively.

These data indicate that the higher incidence of HB in farmers may be caused by their working in rural areas [1,3,4,11-15].

In the majority of endemic countries with BB outbreaks, domestic animals are the chief source of HB infection. In Korea, the period from 1955 to now can be divided into 3 separate phases on the basis of the epidemiological pattern of brucellosis in domestic animals. The first phase “the neglectful period of BB” covers the outbreaks between 1955 and 1983. At that time, BB outbreaks occurred sporadically (only a few cases) until 1983. The second phase “the endemic period of brucellosis outbreaks” spans from 1984 to 2002. The number of infected cattle was over 100 in 1984, and the prevalence of BB has increased continuously. The third phase “the explosive outbreaks of BB” began in 2003. The detection rate of BB has increased sharply since 2003. Meanwhile, the incidence of HB cases, since they were first reported in 2002, showed a corresponding increase with the increase in the number of BB outbreaks in cattle [3,6,9]. A total of 703 cases of HB were reported in Korea during the period from 2002 to 2013.

In conclusion, HB in Korea was mainly concerned with the livestock industry, and infection by unprotected contact was its major route of transmission. This study provides a quantitative analysis of BB and HB outbreaks in Korea and the better planning of future control strategies. In addition, we hope that the information provided by this study will be a useful for

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ן׷׶ֵ׋װש׶ׯ֨ה׭׭ִ֨׭׼֨ש״ֶ

public health sciences as a reference for further studies on brucellosis.

REFERENCES

1. Corbel MJ, Elberg SS, Cosivi O. Brucellosis in humans and animals. World Health Organization (WHO), Geneva. 2006. Available at http://www.who.int/csr/resources/publications/Brucellosis.pdf [accessed on 20 October 2016].

2. Infectious Agent Surveillance Report (IASR). Brucellosis in Japan, April 1999-March 2012. IASR 2012;33:183-185.

3. Park SY, Kim TJ, Yoon H, Kim JY, Lee MJ, Lee WC. A retrospective Study of the Extensive Eradication Program for Brucellosis Outbreaks and Control in Korea 2002-2009. Jpn J Infect Dis 2012;65:427-429.

4. Yoon H, Moon OK, Lee SH, Lee WC, Her M, Jeong W, Jung SC, Kim DS. Epidemiology of brucellosis among cattle in Korea from 2001 to 2011. J Vet Sci 2014;15:537-543.

5. Ministry of Agriculture, Food and Rural Affair (MAFRA).

Standard operation on tuberculosis and brucellosis. Notice 2014-13 (Mar.17, 2014).

6. Animal and Plant Quarantine Agency (QIA). Bovine brucellosis;

Korea Animal Health Integrated System, QIA, 2002-20013.

7. Korea Center for Disease Control and Prevention (KCDC).

Human Brucellosis; Disease by Web Statistical System, KCDC, 2002-2013.

8. Her M, Kang SI, Kim JW, et al. A genetic comparison of Brucella abortus isolates from animal and human by using the MLVA assay. J Microbiol Biotechnol 2010;20:1750-175.

9. Jung S, Cho D, Nam H, et al. Current studies and research trends of bovine brucellosis in Korea. J Vet Pub Health 2007;31:91-104.

10. Lim HS, Min YS, Lee HS. Investigation of a series of brucellosis cases in Gyeonsanbuk-do during 2003-2004. J Prev Med Public Health 2005;38:482-488.

11. Wee SH, Nam HM, Kim CH. Emergence of brucellosis in cattle in Republic of Korea. Vet Rec 2008;162:556-557.

12. Park MS, Woo YS, Lee MJ, et al. The first case of human brucellosis in Korea. Infect. Chemother 2003;35:461-466.

13. Park MY, Lee YS, Park SJ, et al. A Sporadic Outbreaks of Human Brucellosis in Korea. J Korean Med Sci 2005;20:941-946.

14. Dahouk SA, Neubauer H, Hensel A, et al. Changing Epidemiology of Human Brucellosis, Germany, 1962-2005. Emerging Infect Dis 2007;13:1895-1900.

15. Avdikou I, Maipa V, Alamanos Y. Epidemiology of human brucellosis in a defined area of Northwestern Greece. Epidemiol Infect 2005;133:905-910.

지난 10년 동안 인체 브루셀라증은 한국에서 주요한 인수공통전염병이 되었다. 본 연구의 목적은 2002년부터 2013년까지

한국의 소 브루셀라증 발생 관련 인체 브루셀라증에 대한 대규모 방역 프로그램의 역학 동향을 관찰하는 것이다. 본 연구 에 사용된 자료는 질병관리본부 및 농림축산검역본부의 웹 사이트에 있는 2002년부터 2013년 브루셀라증 발병 자료이다. 소 브루셀라증 발생 관련 인체 브루셀라증 발병 건수는 2003년 이후 증가해 2006년에 최고치를 보였으나 이후 감소했다.

이 기간 동안 국내 가축에 감염된 소 브루셀라증은 총 89,240두로 누적발생률은 100,000두당 611.8이었다. 같은 기간 동안 인체 브루셀라증은 총 703명이 발병하여 누적발생률은 100,000명당 0.12이었다. 또한 소와 인체 사이의 브루셀라증 발생 의 상관 계수는 매우 유의했다 (r=+0.985). 소 브루셀라증 1,000건당 인체 브루셀라증 7.88건이 발생하였다. 인체 브루셀 라증 감염을 막기 위해 가축에서 브루셀라증에 대한 광범위한 방제 프로그램이 적용되었고, 이는 인체 브루셀라증 발생을 줄이는데 크게 기여했다.

중심단어소 브루셀라증 발생 관련 인체 브루셀라증, 역학 동향, 방역 프로그램, 한국