Changing Epidemiological Characteristics of Dengue Fever in Chinese Mainland Between 2019 and 2024

Abstract

Background: Dengue fever is a mosquito-borne viral disease caused by the dengue virus, the prevalence of which has sharply increased in recent years worldwide. The indigenous dengue fever epidemic triggered by imported cases continues to pose a serious challenge to public health in China with a trend of expanding towards higher latitudes. The three largest local outbreaks of dengue fever in China since 2014 occurred in 2019, 2023, and 2024. A comparative analysis is needed to identify changes in the epidemiological characteristics of dengue fever during this period and to provide targeted prevention and control measures.

Methods: A descriptive epidemiologic analysis method was performed to compare the basic characteristics of dengue fever between four phases (2019, 2020-2022, 2023, and 2024) with respect to geographic distribution, seasonality, imported sources, and composition of cases. The data on dengue fever cases were obtained from the Chinese Notifiable Reported Infectious Disease System (CNRIDS). The clinical criteria for diagnosing dengue fever were based on the guidebook published by National Health Commission of the People’s Republic of China.

Results: Between 2019 and 2024 a total of 67,389 cases of dengue fever were reported in mainland China, including 8189 imported and 59,200 indigenous cases. In 2024, the reported cases of dengue fever covered 28 provincial-level administrative divisions (PLADs), 217 cities, and 895 counties with more involved areas than 2023 (28 PLADs, 195 cities, and 739 counties) but less than 2019 (29 PLADs, 246 cities, and 1269 counties). Dengue fever cases were located primarily on border areas of Yunnan (21,309 [36.0%]) and the Pearl River Delta region (15,829 [26.7%]). Most imported dengue cases (92.1% [7546/8189]) of imported cases originated from the Southeast Asian region. The rapid growth of indigenous cases (weekly reported cases > 500) in 2023 started 3 weeks earlier than 2019. In 2024 the local outbreak of dengue fever exhibited the earliest onset and had the longest duration (238 days [3 May-27 December]) compared to 218 days (25 May-29 December) in 2023 and 202 days (24 May-11 December) in 2019. Inter-provincial transmission of dengue fever rose progressively between 2019 and 2024, as follows: 2.4% (2019); 6.2% (2023); and 6.5% (2024). Notably, Yunnan accounted for 90.1% of total inter-provincial transmission of dengue fever in 2023, whereas Guangdong became the primary source in 2024 (96.4%).

Keywords

dengue fever / epidemiological characteristics / prevention

References

[1] WHO. Global Strategy for Dengue Prevention and Control, 2012-2020. 2012 Aug 22 [2024-12-01]. Available from: https://www.who.int/publications/i/item/9789241504034.

[2] WHO. Dengue and Severe Dengue. 2024 Apr 23 [ 2024-12-01]. Available from: https://www.who.int/news-room/fact-sheets/detail/dengue-and-severe-dengue.

[3] The Lancet . Dengue: the threat to health now and in the future. Lancet. 2024; 404(10450): 311.

[4] Haider N, Hasan MN, Onyango J, Asaduzzaman M. Global landmark: 2023 marks the worst year for dengue cases with millions infected and thousands of deaths reported. IJID Reg. 2024; 13: 100459.

[5] Khan MB, Yang Z-S, Lin C-Y, Hsu M-C, Urbina AN, Assavalapsakul W, et al. Dengue overview: an updated systemic review. J Infect Public Health. 2023; 16(10): 1625-1642.

[6] Zhao Z, Yue Y, Liu X, Li C, Ma W, Liu Q. The patterns and driving forces of dengue invasions in China. Infect Dis Poverty. 2023; 12(1): 42.

[7] Sang S, Yue Y, Wang Y, Zhang X. The epidemiology and evolutionary dynamics of massive dengue outbreak in China, 2019. Front Microbiol. 2023; 14: 1156176.

[8] Wu T, Wu Z, Li Y-P. Dengue fever and dengue virus in the People’s Republic of China. Rev Med Virol. 2022; 32(1): e2245.

[9] Lin H, Wang X, Li Z, Li K, Lin C, Yang H, et al. Epidemiological characteristics of dengue in mainland China from 1990 to 2019: a descriptive analysis. Medicine (Baltimore). 2020; 99(36): e21982.

[10] Lun X, Yang R, Lin L, Wang Y, Wang J, Guo Y, et al. Effects of the source of information and knowledge of dengue fever on the mosquito control behavior of residents of border areas of Yunnan, China. Parasit Vectors. 2023; 16(1): 311.

[11] Li Z, Huang X, Li A, Du S, He G, Li J. Epidemiological characteristics of dengue fever - China, 2005-2023. China CDC Wkly. 2024; 6(41): 1045-1048.

[12] Wang B, Li Y, Feng Y, Zhou H, Liang Y, Dai J, et al. Phylogenetic analysis of dengue virus reveals the high relatedness between imported and local strains during the 2013 dengue outbreak in Yunnan, China: a retrospective analysis. BMC Infect Dis. 2015; 15: 142.

[13] WHO. Western Pacific Emergencie Dengue Situation Update. 2024 Dec 12 [ 2024-12-01]. Available from: https://www.who.int/westernpacific/wpro-emergencies/surveillance/dengue.

[14] Li N, Feng Y, Vrancken B, Chen Y, Dong L, Yang Q, et al. Assessing the impact of COVID-19 border restrictions on dengue transmission in Yunnan Province, China: an observational epidemiological and phylogenetic analysis. Lancet Reg Health West Pac. 2021; 14: 100259.

[15] Abdalgader T, Zheng Z, Banerjee M, Zhang L. The timeline of overseas imported cases acts as a strong indicator of dengue outbreak in mainland China. Chaos. 2024; 34(8): 083106.

[16] People’s Government of Yunnan Province. Yunnan Province Online Press Conference Hall. 2024 Jan 19 [ 2024-12-01]. Available from: https://www.yn.gov.cn/ynxwfbt/html/2024/zuixinbaodao_0124/6479.html.

[17] Feng Y, Chang F, Yang Y, Lu H. From dengue to chikungunya: guangdong as a sentinel for arboviral threats in East Asia. Biosci Trends. 2025.

[18] Kolimenakis A, Heinz S, Wilson ML, Winkler V, Yakob L, Michaelakis A, et al. The role of urbanisation in the spread of Aedes mosquitoes and the diseases they transmit-a systematic review. PLoS Negl Trop Dis. 2021; 15(9): e0009631.

[19] Wang MS, Hu T, Hu YM, Du H, Dong SR. Analysis of the anomalous characteristics and causes of pre-flood season precipitation in Guangdong in 2024. Guangdong Meteorol. Published online June 9. [Epub ahead of print]

[20] Guzman MG, Harris E. Dengue. Lancet. 2015; 385(9966): 453-465.

[21] The Lancet Infectious Diseases. Can we control dengue? Lancet Infect Dis. 2023; 23(10): 1095.

[22] Cazelles B, Cazelles K, Tian H, Chavez M, Pascual M. Disentangling local and global climate drivers in the population dynamics of mosquito-borne infections. Sci Adv. 2023; 9(39): eadf7202.

[23] Mokhtar S, Pittman Ratterree DC, Britt AF, Fisher R, Ndeffo-Mbah ML. Global risk of dengue outbreaks and the impact of El Niño events. Environ Res. 2024; 262(Pt 1): 119830.

[24] National Centers for Environmental Information. Annual 2023 Global Climate Report. 2024 Jan [ 2024-12-01]. Available from: https://www.ncei.noaa.gov/access/monitoring/monthly-report/global/202313.

[25] Soukavong M, Thinkhamrop K, Pratumchart K, Soulaphy C, Xangsayarath P, Mayxay M, et al. Bayesian spatio-temporal analysis of dengue transmission in Lao PDR. Sci Rep. 2024; 14(1): 21327.

[26] Zaw W, Lin Z, Ko Ko J, Rotejanaprasert C, Pantanilla N, Ebener S, et al. Dengue in Myanmar: spatiotemporal epidemiology, association with climate and short-term prediction. PLoS Negl Trop Dis. 2023; 17(6): e0011331.