Skip Navigation
Skip to contents

PHRP : Osong Public Health and Research Perspectives

OPEN ACCESS
SEARCH
Search

Articles

Page Path
HOME > Osong Public Health Res Perspect > Volume 7(1); 2016 > Article
Brief Report Comparison of the Epidemiological Aspects of Imported Dengue Cases between Korea and Japan, 2006–2010
Young Eui Jeong, Won-Chang Lee, Jung Eun Cho, Myung-Guk Han, Won-Ja Lee
Osong Public Health and Research Perspectives 2015;7(1):71-74.
DOI: https://doi.org/10.1016/j.phrp.2015.12.001
Published online: December 12, 2015
  • 1,334 Views
  • 17 Download
  • 12 Crossref
  • 10 Scopus

aDivision of Arboviruses, National Institute of Health, Korea Centers for Disease Control and Prevention, Cheongju, Korea

bCollege of Veterinary Medicine, Konkuk University, Seoul, Korea

• Received: July 14, 2015   • Revised: October 30, 2015   • Accepted: December 1, 2015

Copyright © 2015 Korea Centers for Disease Control and Prevention. Published by Elsevier Korea LLC.

This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

  • To compare the epidemiological characteristics of dengue cases imported by travelers or immigration in both Korea and Japan, we determined dengue incidence and related risk factors. During 2006–2010, 367 and 589 imported dengue cases were reported in Korea and Japan, respectively. In Korea, the presumptive origins for the dengue infections were Southeast Asia (82.6%), Southern Asia (13.9%), Eastern Asia (1.1%), South America (0.3%), Central America (0.3%), Africa (0.3%), and other countries (1.6%). In Japan, the origins of the infections were Southeast Asia (69.8%), Southern Asia (20.0%), Eastern Asia (1.7%), South America (2.5%), Central America (1.2%), Africa (1.2%), Oceania (2.4%), and other countries (1.2%). In both countries, more dengue cases were reported for men than for women (p < 0.01), and those aged 20–30 years accounted for > 60% of the total cases. The frequency of imported cases in summer and autumn (∼70% of total cases) was similar in both countries. This study demonstrates that there is a similar pattern of imported dengue cases in Korea and Japan. Therefore, there is a risk of an autochthonous dengue outbreak in Korea, as indicated by the recent outbreak in Japan in 2014.
Dengue fever (DF) is a mosquito-borne febrile disease caused by dengue virus (DENV), which belongs to the genus Flavivirus of the family Flaviviridae [1]. Four distinct serotypes of the virus (DENV-1–DENV-4) cause various forms of illness from mild fever to severe dengue [2]. According to the latest World Health Organization report, 50–100 million annual dengue infections have been estimated in >100 countries [3].
The virus is transmitted mainly by Aedes aegypti and Aede albopictus mosquitoes 2, 3. The Aedes aegypti mosquito, the principal vector, usually lives in regions where the winter isotherm is maintained at ≥ 10°C [3]. Because both Korea and Japan are located above this winter isotherm, the Aedes aegypti mosquito cannot survive. However, Aedes albopictus mosquito, a secondary vector, is abundant in both countries 4, 5. Thus, both countries could be at risk of dengue establishment.
In Korea, no indigenous dengue cases have been confirmed, and all reported cases were diagnosed in travelers returning from endemic or epidemic countries 6, 7, 8. In Korea, DF was legally classified as a notifiable infectious disease in August 2000. DF is a notifiable infectious disease in Japan, designated by the Infectious Disease Control Law in 1999 9, 10. In Japan, there were DF outbreaks between 1942 and 1945; however, no domestic cases were reported prior to 2014 9, 10, 11 when Japan experienced an unexpected small dengue outbreak in 2014 [12].
In this study, we conducted a comparative observation of the epidemiological characteristics and risk factors of DF between Korea and Japan during 2006 to 2010.
We used raw data of 367 DF cases in Korea between 2006 and 2010, which were obtained from the infectious diseases surveillance yearbook available on the Korea Centers for Disease Control and Prevention website [13]. Data of 589 DF cases in Japan during the same time period were obtained from Annual Surveillance Data and the Infectious Diseases Weekly Report, both available on the Infectious Diseases Surveillance Center (IDSC) website 14, 15.
To better quantify the impact of DF on health in Korea and Japan, we compiled and analyzed the prevalence rate (PR) per 100,000 population and related risk factors such as sex, age, seasonal distribution, and the geographic origin of infection. The regions were defined based on the above data set. Information on length of travel and nationality of patients was not available. The PR was calculated as the number of reported cases divided by the midyear population based on the resident registration, multiplied by 100,000. Statistical analysis was performed using Excel 2007 statistical software (Microsoft Corp., Redmond, WA, USA). The Chi-square test was used to assess whether differences according to each variable are statistically associated. A p value < 0.05 was considered statistically significant.
Table 1 shows the PR and travel destination of imported dengue cases in Korea and Japan between 2006 and 2010. The average PR of imported DF was 0.15 per 100,000 population, with 35–125 annual notifications, in Korea and 0.09 per 100,000 population, with 58–245 annual notifications, in Japan. These values may be underestimated because a number of dengue cases are not immediately apparent, and these patients are not likely to see a doctor. Koreans and Japanese tend to travel to developing Asian countries 16, 17, where the risk for DF is significantly higher than in other countries. The most frequently suspected region as the origin of infection was Southeast Asia (p < 0.01) in both countries. The frequencies of Southern Asia, South America, and Oceania as the origins of infection were much lower in Korean travelers than in Japanese travelers. Therefore, the incidence of imported dengue is influenced by travel destinations. Table 2 shows the comparison of the epidemiological aspects of sex, age, and seasonality. More cases were men than women in both Korea (65.7% vs. 34.3%, p < 0.01) and Japan (64.9% vs. 35.1%, p < 0.01). The proportion of infections by sex was similar in both countries. The data may represent a difference in activities associated with exposure between men and women.
DF is typically acknowledged as a childhood disease and is an important cause of pediatric hospitalization in Southeast Asia. However, there is evidence of an increasing incidence of DF in older age groups 2, 3, 18. The distribution of infection by age group was similar in Korea and Japan, with >60% of the cases occurring in those aged 20–39 years (p < 0.01). The incidence was higher between August and October than other seasons in both Korea and Japan (p < 0.01). This specific period represents the time when people in both countries are likely to take vacations.
In conclusion, this study demonstrates that there is a substantial amount of imported dengue cases in Korea and Japan. There is a risk of an autochthonous outbreak with a higher number of imported dengue cases, as indicated by the recent dengue outbreak in Japan in 2014. To minimize the number of imported dengue cases, timely information on dengue epidemics should be routinely provided to the medical community and individuals who are planning travel abroad.
The authors declare that there is no conflict of interests regarding the publication of this paper.
This study was undertaken with a fund from the National Institute of Health, Korea Centers for Disease Control & Prevention (code: 4847-311-210, 4847-301-210).
  • 1. Knipe D.M., Howley D.M.. Fields virolgy. Flaviviridae. 5th ed.2007, Lippincott-Raven Publishers. Philadelphia (US), pp 1101. -1113. Ch33.
  • 2. http://www.who.int/mediacentre/factsheets/fs117/en/.
  • 3. World Health Organization (WHO) . Dengue: guidelines for diagnosis, treatment, prevention and control. 2009, WHO. Geneva, pp 3. -21. Chapter 1.
  • 4. Nihei N., Komagata O., Mochizuki K.. Geospatial analysis of invasion of the Asian tiger mosquito Aedes albopictus: competition with Aedes japonicus japonicus in its northern limit area in Japan. Geospat Health 8(2): 2014 May;417-427. PMID: 24893018.Article
  • 5. Takhampunya R., Kim H.C., Tippayachai B.. Distribution and mosquito hosts of Chaoyang virus, a newly reported flavivirus from the Republic of Korea, 2008–2011. J Med Entomol 51(2): 2014 Mar;464-474. PMID: 24724298.Article
  • 6. Jeong Y.E., Kim Y.H., Cho J.E.. Identification of Dengue Type 1 Virus (DENV-1) in Koreans traveling abroad. Osong Public Health Res Perspect 2(1): 2011 Jun;34-40. PMID: 24159448.Article
  • 7. Park S.H., Lee M.J., Baek J.H.. Epidemiological aspects of exotic malaria and dengue fever in travelers in Korea. J Clin Med Res 3(3): 2011 May;139-142. PMID: 21811545.Article
  • 8. Park J.H., Lee D.W.. Dengue fever in South Korea, 2006–2010. Emerg Infect Dis 18(9): 2012 Sep;1525-1527. PMID: 22931747.Article
  • 9. Nakamura N., Arima Y., Shimada T.. Incidence of dengue virus infection among Japanese travellers, 2006 to 2010. Western Pac Surveill Response J 3(2): 2012 Jun;39-45. PMID: 23908911.Article
  • 10. Takasaki T.. Imported dengue fever/dengue hemorrhagic fever cases in Japan. Trop Med Health 39(4 Suppl.): 2011 Dec;13-15. PMID: 22500132.Article
  • 11. National Institute of Infectious Diseases and Tuberculosis and Infectious Diseases Control Division . Ministry of Health, Labor and Welfare of Japan. Imported dengue fever and dengue hemorrhagic fever in Japan, as of July 2007. IASR 28:2007 Jul;213-214.
  • 12. Kutsuna S., Kato Y., Moi M.L.. Autochthonous dengue fever, Tokyo, Japan, 2014. Emerg Infect Dis 21(3): 2015 Mar;517-520. PMID: 25695200.Article
  • 13. http://www.cdc.go.kr/.
  • 14. http://idsc.nih.go.jp/idwr/ydata/report-Ea.html.
  • 15. http://idsc.nih.go.jp/idwr/kanja/idwr/idwr2011/idwr2011-22.pdf.
  • 16. http://kosis.kr.
  • 17. http://www.tourism.jp/en/statistics/outbound/.
  • 18. Guha-Sapir D., Schimmer B.. Dengue fever: new paradigms for a changing epidemiology. Emerg Themes Epidemiol 2(1): 2005 Mar;1PMID: 15743532.Article
Table 1
Comparison of the prevalence of dengue infection and geographical origin of infections between Korea and Japan, 2006–2010.
Korea
Japan
No. of cases (%) 95% CI No. of cases (%) 95% CI
No. of cases 367 589
Prevalence rate 0.15 0.06–0.24 0.09 0.07–0.11
Region
 Southeast Asia: 303 (82.6) 78.3–86.1 411 (69.8) 65.1–72.5
 The Philippines 118 (32.2) 27.6–37.1 83 (14.1) 11.3–16.9
 Indonesia 55 (15.0) 11.7–19.0 146 (24.8) 21.3–38.2
 Thailand 42 (11.4) 8.6–15.1 64 (10.9) 7.7–14.1
 Vietnam 30 (8.2) 5.8–11.5 26 (4.4) 2.7–6.1
 Cambodia 27 (7.4) 5.1–10.5 20 (3.4) 1.9–4.8
 Laos 12 (3.3) 1.8–5.7 12 (2.0) 0.9–3.1
 Malaysia 10 (2.7) 1.4–5.0 24 (4.1) 2.5–5.0
 Myanmar 6 (1.6) 0.7–3.6 6 (1.0) 0.2–1.8
 Singapore 1 (0.3) 6 (1.0) 0.2–1.8
 East Timor 2 (0.5) 5 (0.8)
 Others 19 (3.2) 1.8–3.6
 Southern Asia: 51(13.9) 10.7–17.8 118 (20.0) 17.8–24.4
 India 39 (10.6) 7.9–14.2 90 (15.3) 12.4–18.2
 Pakistan 1 (0.2)
 Bangladesh 6 (1.6) 0.7–3.6 10 (1.7) 0.7–2.7
 Maldives 3 (0.8) 0.2–2.5 4 (0.7)
 Nepal 2 (0.3)
 Sri Lanka 2 (0.5) 6 (1.0) 0.2–1.8
 Others 1 (0.3) 5 (0.8)
Eastern Asia: 4 (1.1) 0.3–2.9 10 (1.7) 0.7–2.74
 China 3 (0.8)
 Taiwan 1 (0.3) 1 (0.2)
 Others 9 (1.5) 0.5–2.5
 South America 1 (0.3) 15 (2.5) 1.3–3.9
 Central America 1 (0.3) 7 (1.2) 0.3–2.0
 Africa 1 (0.3) 7 (1.2) 0.3–2.0
 Oceania 14 (2.4) 1.2–3.6
 Other countries 6 (1.6) 0.7–3.6 7 (1.2) 0.3–2.0
p p < 0.01 p < 0.01
Total 367 (100) 589 (100)

The Chi-square test was used to assess whether differences according to each variable are statistically associated.

Prevalence rate per 100,000 population.

CI = confidence interval.

Table 2
Comparison of epidemiological aspects of imported dengue in terms of sex, age, and seasons between Korea and Japan, 2006–2010.
Korea
Japan
No. of cases (%) 95% CI No. of cases (%) 95% CI
No of cases 367 589
Sex
 Male 241 (65.7) 60.7–70.3 382 (64.9) 60.9–68.7
 Female 126 (34.3) 29.7–39.3 207 (35.1) 31.4–39.1
 p p < 0.01 p < 0.01
Age (y)
 < 9 2 (0.5) 0.02–2.10 13 (2.2) 1.3–3.8
 10–19 35 (9.5) 6.9–13.0 45 (7.6) 5.7–10.1
 20–29 119 (32.4) 27.8–37.4 239 (40.6) 36.7–44.6
 30–39 106 (28.9) 24.5–33.7 126 (21.4) 18.3–24.9
 40–49 63 (17.2) 13.6–21.4 92 (15.6) 12.9–18.8
 50–59 32 (8.7) 6.2–12.16 40 (6.8) 5.0–9.1
 > 60 10 (2.7) 1.4–5.0 34 (5.8) 4.1–8.0
 p p < 0.01 p < 0.01
Seasonality
 Spring (Mar–May) 42 (11.4) 8.6–15.1 91 (15.9) 13.1–19.1
 Summer (Jun–Aug) 119 (32.4) 27.8–37.4 172 (30.0) 26.4–33.8
 Autumn (Sep–Nov) 143 (39.0) 34.1–44.0 228 (39.7) 35.8–43.8
 Winter (Dec–Feb) 63 (17.2) 13.6–21.4 83 (14.5) 11.8–17.6
p p < 0.01 p < 0.01

The Chi-square test was used to assess whether differences according to each variable are statistically associated.

CI = confidence interval.

Figure & Data

References

    Citations

    Citations to this article as recorded by  
    • Molecular and Haematological Analysis of Dengue Virus-3 Among Children in Lahore, Pakistan
      Muhammad Kashif, Muhammad Afzal, Basit Zeshan, Hasnain Javed, Salma Batool, Modasrah Mazhar
      Jundishapur Journal of Microbiology.2021;[Epub]     CrossRef
    • Molecular evolution of dengue virus types 1 and 4 in Korean travelers
      Eun-Ha Hwang, Green Kim, Hoyin Chung, Hanseul Oh, Jong-Hwan Park, Gyeung Haeng Hur, JungJoo Hong, Bon-Sang Koo
      Archives of Virology.2021; 166(4): 1103.     CrossRef
    • Aedes albopictus and Aedes flavopictus (Diptera: Culicidae) pre-imaginal abundance patterns are associated with different environmental factors along an altitudinal gradient
      Luis Fernando Chaves, Mariel D. Friberg
      Current Research in Insect Science.2021; 1: 100001.     CrossRef
    • Evolution, heterogeneity and global dispersal of cosmopolitan genotype of Dengue virus type 2
      Surya Pavan Yenamandra, Carmen Koo, Suzanna Chiang, Han Shi Jeri Lim, Zhen Yuan Yeo, Lee Ching Ng, Hapuarachchige Chanditha Hapuarachchi
      Scientific Reports.2021;[Epub]     CrossRef
    • Temporal Trend of Aedes albopictus in Local Urban Parks of the Republic of Korea
      Myung-Jae Hwang, Jong-Hun Kim, Heung-Chul Kim, Myung Soon Kim, Terry A Klein, Juhwa Choi, Kisung Sim, Yeonseung Chung, Yadav Prasad Joshi, Hae-Kwan Cheong, Kristen Healy
      Journal of Medical Entomology.2020; 57(4): 1082.     CrossRef
    • A Two-Patch Mathematical Model for Temperature-Dependent Dengue Transmission Dynamics
      Jung Kim, Yongin Choi, James Kim, Sunmi Lee, Chang Lee
      Processes.2020; 8(7): 781.     CrossRef
    • Potential effects of climate change on dengue transmission dynamics in Korea
      Hyojung Lee, Jung Eun Kim, Sunmi Lee, Chang Hyeong Lee, Shamala Devi Sekaran
      PLOS ONE.2018; 13(6): e0199205.     CrossRef
    • Analysis of dengue virus burden and serotypes pattern in Faisalabad, 2016–2017
      Muhammad Yousaf, Kashaf Junaid, Muhammad Sarfaraz Iqbal, Imran Aslam, Sheraz Ahmad, Muhammad Aqeel, Usman Ali Ashfaq, Saba Khaliq, Muhammad Usman Ghani, Nayyar Waqar
      Future Virology.2018; 13(4): 245.     CrossRef
    • Seroprevalence of Toxoplasmosis with ELISA and Rapid Diagnostic Test among Residents in Gyodong-do, Inchon city, Korea: A Four-Year Follow-up
      Yeong Hoon Kim, Ji hoo Lee, Seong kyu Ahn, Tong-Soo Kim, Sung-Jong Hong, Chom-Kyu Chong, Hye-Jin Ahn, Ho-Woo Nam
      The Korean Journal of Parasitology.2017; 55(3): 247.     CrossRef
    • A Disease Around the Corner
      Hae-Wol Cho, Chaeshin Chu
      Osong Public Health and Research Perspectives.2016; 7(1): 1.     CrossRef
    • WITHDRAWN: A disease around the corner
      Hae-Wol Cho, Chaeshin Chu
      Osong Public Health and Research Perspectives.2016;[Epub]     CrossRef
    • Prospects for dengue vaccines for travelers
      Sl-Ki Lim, Yong Seok Lee, Suk Namkung, Jacqueline K Lim, In-Kyu Yoon
      Clinical and Experimental Vaccine Research.2016; 5(2): 89.     CrossRef


    PHRP : Osong Public Health and Research Perspectives