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Li H, Yang Y, Chen J, Li Q, Chen Y, Zhang Y, Cai S, Zhan M, Wu C, Lin X, Xiang J. Epidemiological Characteristics of Overseas-Imported Infectious Diseases Identified through Airport Health-Screening Measures: A Case Study on Fuzhou, China. Trop Med Infect Dis 2024; 9:138. [PMID: 38922050 PMCID: PMC11209573 DOI: 10.3390/tropicalmed9060138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2024] [Revised: 06/10/2024] [Accepted: 06/12/2024] [Indexed: 06/27/2024] Open
Abstract
BACKGROUND This study aimed to examine the epidemiological characteristics of imported infections and assess the effectiveness of border health screening in detecting imported diseases. METHODS We obtained infection data for 2016 to 2019 from the Fuzhou Changle International Airport Infection Reporting System. The demographic, temporal, and spatial characteristics of travel-related infections were analyzed using r×c contingency tables, the Cochran-Armitage trend test, and seasonal-trend decomposition using LOESS (STL). Detection rates were used as a proxy for the effectiveness of border health-screening measures. RESULTS Overall, 559 travel-related infections were identified during the study period, with 94.3% being imported infections. Airport health screening demonstrated an overall effectiveness of 23.7% in identifying travel-associated infections. Imported infections were predominantly identified in males, with 55.8% of cases occurring in individuals aged 20-49. The peak periods of infection importation were from January to February and from May to August. The infectious diseases identified were imported from 25 different countries and regions. All dengue fever cases were imported from Southeast Asia. Most notifiable infections (76.0%) were identified through fever screening at the airport. CONCLUSION The increasing number of imported infections poses a growing challenge for public health systems. Multifaceted efforts including surveillance, vaccination, international collaboration, and public awareness are required to mitigate the importation and spread of infectious diseases from overseas sources.
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Affiliation(s)
- Hong Li
- School of Public Health, Fujian Medical University, Fuzhou 350122, China; (H.L.); (Y.Y.); (J.C.); (Q.L.); (Y.C.); (Y.Z.); (C.W.)
- Key Laboratory of Environment and Health, Fujian Province University, Fuzhou 350122, China
- School of Public Health and Health Management, Fujian Health College, Fuzhou 350101, China
| | - Yan Yang
- School of Public Health, Fujian Medical University, Fuzhou 350122, China; (H.L.); (Y.Y.); (J.C.); (Q.L.); (Y.C.); (Y.Z.); (C.W.)
- Key Laboratory of Environment and Health, Fujian Province University, Fuzhou 350122, China
| | - Jiake Chen
- School of Public Health, Fujian Medical University, Fuzhou 350122, China; (H.L.); (Y.Y.); (J.C.); (Q.L.); (Y.C.); (Y.Z.); (C.W.)
- Key Laboratory of Environment and Health, Fujian Province University, Fuzhou 350122, China
| | - Qingyu Li
- School of Public Health, Fujian Medical University, Fuzhou 350122, China; (H.L.); (Y.Y.); (J.C.); (Q.L.); (Y.C.); (Y.Z.); (C.W.)
- Key Laboratory of Environment and Health, Fujian Province University, Fuzhou 350122, China
| | - Yifeng Chen
- School of Public Health, Fujian Medical University, Fuzhou 350122, China; (H.L.); (Y.Y.); (J.C.); (Q.L.); (Y.C.); (Y.Z.); (C.W.)
- Key Laboratory of Environment and Health, Fujian Province University, Fuzhou 350122, China
| | - Yilin Zhang
- School of Public Health, Fujian Medical University, Fuzhou 350122, China; (H.L.); (Y.Y.); (J.C.); (Q.L.); (Y.C.); (Y.Z.); (C.W.)
- Key Laboratory of Environment and Health, Fujian Province University, Fuzhou 350122, China
| | - Shaojian Cai
- Department of Emergency Preparedness and Response, Fujian Provincial Center for Diseases Control and Prevention, Fuzhou 350012, China; (S.C.); (M.Z.)
| | - Meirong Zhan
- Department of Emergency Preparedness and Response, Fujian Provincial Center for Diseases Control and Prevention, Fuzhou 350012, China; (S.C.); (M.Z.)
| | - Chuancheng Wu
- School of Public Health, Fujian Medical University, Fuzhou 350122, China; (H.L.); (Y.Y.); (J.C.); (Q.L.); (Y.C.); (Y.Z.); (C.W.)
- Key Laboratory of Environment and Health, Fujian Province University, Fuzhou 350122, China
| | - Xinwu Lin
- Entry Health Screening Office, Fuzhou Customs, Changle International Airport, Fuzhou 350209, China
| | - Jianjun Xiang
- School of Public Health, Fujian Medical University, Fuzhou 350122, China; (H.L.); (Y.Y.); (J.C.); (Q.L.); (Y.C.); (Y.Z.); (C.W.)
- Key Laboratory of Environment and Health, Fujian Province University, Fuzhou 350122, China
- School of Public Health, The University of Adelaide, North Terrace Campus, Adelaide, SA 5005, Australia
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Zhao L, Guo X, Li L, Jing Q, Ma J, Xie T, Lin D, Li L, Yin Q, Wang Y, Zhang X, Li Z, Liu X, Hu T, Hu M, Ren W, Li J, Peng J, Yu L, Peng Z, Hong W, Leng X, Luo L, Ngobeh JJK, Tang X, Wu R, Zhao W, Shi B, Liu J, Yang Z, Chen XG, Zhou X, Zhang F. Phylodynamics unveils invading and diffusing patterns of dengue virus serotype-1 in Guangdong, China from 1990 to 2019 under a global genotyping framework. Infect Dis Poverty 2024; 13:43. [PMID: 38863070 PMCID: PMC11165891 DOI: 10.1186/s40249-024-01211-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2024] [Accepted: 05/29/2024] [Indexed: 06/13/2024] Open
Abstract
BACKGROUND The strong invasiveness and rapid expansion of dengue virus (DENV) pose a great challenge to global public health. However, dengue epidemic patterns and mechanisms at a genetic scale, particularly in term of cross-border transmissions, remain poorly understood. Importation is considered as the primary driver of dengue outbreaks in China, and since 1990 a frequent occurrence of large outbreaks has been triggered by the imported cases and subsequently spread to the western and northern parts of China. Therefore, this study aims to systematically reveal the invasion and diffusion patterns of DENV-1 in Guangdong, China from 1990 to 2019. METHODS These analyses were performed on 179 newly assembled genomes from indigenous dengue cases in Guangdong, China and 5152 E gene complete sequences recorded in Chinese mainland. The genetic population structure and epidemic patterns of DENV-1 circulating in Chinese mainland were characterized by phylogenetics, phylogeography, phylodynamics based on DENV-1 E-gene-based globally unified genotyping framework. RESULTS Multiple serotypes of DENV were co-circulating in Chinese mainland, particularly in Guangdong and Yunnan provinces. A total of 189 transmission clusters in 38 clades belonging to 22 subgenotypes of genotype I, IV and V of DENV-1 were identified, with 7 Clades of Concern (COCs) responsible for the large outbreaks since 1990. The epidemic periodicity was inferred from the data to be approximately 3 years. Dengue transmission events mainly occurred from Great Mekong Subregion-China (GMS-China), Southeast Asia (SEA), South Asia Subcontinent (SASC), and Oceania (OCE) to coastal and land border cities respectively in southeastern and southwestern China. Specially, Guangzhou was found to be the most dominant receipting hub, where DENV-1 diffused to other cities within the province and even other parts of the country. Genome phylogeny combined with epidemiological investigation demonstrated a clear local consecutive transmission process of a 5C1 transmission cluster (5C1-CN4) of DENV-1 in Guangzhou from 2013 to 2015, while the two provinces of Guangdong and Yunnan played key roles in ongoing transition of dengue epidemic patterns. In contextualizing within Invasion Biology theories, we have proposed a derived three-stage model encompassing the stages of invasion, colonization, and dissemination, which is supposed to enhance our understanding of dengue spreading patterns. CONCLUSIONS This study demonstrates the invasion and diffusion process of DENV-1 in Chinese mainland within a global genotyping framework, characterizing the genetic diversities of viral populations, multiple sources of importation, and periodic dynamics of the epidemic. These findings highlight the potential ongoing transition trends from epidemic to endemic status offering a valuable insight into early warning, prevention and control of rapid spreading of dengue both in China and worldwide.
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Affiliation(s)
- Lingzhai Zhao
- Institute of Infectious Diseases, Guangzhou Eighth People's Hospital, Guangzhou Medical University, Guangzhou, 510440, Guangdong, China
| | - Xiang Guo
- Department of Pathogen Biology, School of Public Health, Institute of Tropical Medicine, Southern Medical University; Guangdong Provincial Key Laboratory of Tropical Disease Research; Key Laboratory of Prevention and Control for Emerging Infectious Diseases of Guangdong Higher Institutes; Key Laboratory of Infectious Diseases Research in South China of Ministry of Education, Guangzhou, 510515, China
| | - Liqiang Li
- Department of Clinical Laboratory, The Third People's Hospital of Shenzhen, Southern University of Science and Technology, National Clinical Research Center for Infectious Diseases, Guangdong Provincial Clinical Research Center for Infectious Diseases (Tuberculosis), Shenzhen Clinical Research Center for Tuberculosis, Shenzhen, China
| | - Qinlong Jing
- Guangzhou Center for Disease Control and Prevention, Guangzhou, 510440, China
| | - Jinmin Ma
- BGI-Shenzhen, Shenzhen, 518083, China
| | - Tian Xie
- Department of Pathogen Biology, School of Public Health, Institute of Tropical Medicine, Southern Medical University; Guangdong Provincial Key Laboratory of Tropical Disease Research; Key Laboratory of Prevention and Control for Emerging Infectious Diseases of Guangdong Higher Institutes; Key Laboratory of Infectious Diseases Research in South China of Ministry of Education, Guangzhou, 510515, China
| | | | - Li Li
- Department of Biostatistics, School of Public Health, State Key Laboratory of Organ Failure Research, Guangdong Provincial Key Laboratory of Tropical Disease Research, Southern Medical University, Guangzhou, 510515, China
| | - Qingqing Yin
- Department of Pathogen Biology, School of Public Health, Institute of Tropical Medicine, Southern Medical University; Guangdong Provincial Key Laboratory of Tropical Disease Research; Key Laboratory of Prevention and Control for Emerging Infectious Diseases of Guangdong Higher Institutes; Key Laboratory of Infectious Diseases Research in South China of Ministry of Education, Guangzhou, 510515, China
| | - Yuji Wang
- Department of Pathogen Biology, School of Public Health, Institute of Tropical Medicine, Southern Medical University; Guangdong Provincial Key Laboratory of Tropical Disease Research; Key Laboratory of Prevention and Control for Emerging Infectious Diseases of Guangdong Higher Institutes; Key Laboratory of Infectious Diseases Research in South China of Ministry of Education, Guangzhou, 510515, China
| | - Xiaoqing Zhang
- Department of Pathogen Biology, School of Public Health, Institute of Tropical Medicine, Southern Medical University; Guangdong Provincial Key Laboratory of Tropical Disease Research; Key Laboratory of Prevention and Control for Emerging Infectious Diseases of Guangdong Higher Institutes; Key Laboratory of Infectious Diseases Research in South China of Ministry of Education, Guangzhou, 510515, China
| | - Ziyao Li
- Department of Pathogen Biology, School of Public Health, Institute of Tropical Medicine, Southern Medical University; Guangdong Provincial Key Laboratory of Tropical Disease Research; Key Laboratory of Prevention and Control for Emerging Infectious Diseases of Guangdong Higher Institutes; Key Laboratory of Infectious Diseases Research in South China of Ministry of Education, Guangzhou, 510515, China
| | - Xiaohua Liu
- Department of Pathogen Biology, School of Public Health, Institute of Tropical Medicine, Southern Medical University; Guangdong Provincial Key Laboratory of Tropical Disease Research; Key Laboratory of Prevention and Control for Emerging Infectious Diseases of Guangdong Higher Institutes; Key Laboratory of Infectious Diseases Research in South China of Ministry of Education, Guangzhou, 510515, China
| | - Tian Hu
- Department of Pathogen Biology, School of Public Health, Institute of Tropical Medicine, Southern Medical University; Guangdong Provincial Key Laboratory of Tropical Disease Research; Key Laboratory of Prevention and Control for Emerging Infectious Diseases of Guangdong Higher Institutes; Key Laboratory of Infectious Diseases Research in South China of Ministry of Education, Guangzhou, 510515, China
| | - Minling Hu
- Department of Pathogen Biology, School of Public Health, Institute of Tropical Medicine, Southern Medical University; Guangdong Provincial Key Laboratory of Tropical Disease Research; Key Laboratory of Prevention and Control for Emerging Infectious Diseases of Guangdong Higher Institutes; Key Laboratory of Infectious Diseases Research in South China of Ministry of Education, Guangzhou, 510515, China
| | - Wenwen Ren
- Department of Pathogen Biology, School of Public Health, Institute of Tropical Medicine, Southern Medical University; Guangdong Provincial Key Laboratory of Tropical Disease Research; Key Laboratory of Prevention and Control for Emerging Infectious Diseases of Guangdong Higher Institutes; Key Laboratory of Infectious Diseases Research in South China of Ministry of Education, Guangzhou, 510515, China
| | - Jun Li
- Guangdong Provincial Key Laboratory of Research On Emergency in TCM, Guangdong Provincial Hospital of Traditional Chinese Medicine, Guangzhou, 510120, China
| | - Jie Peng
- Department of Infectious Diseases, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, China
| | - Lei Yu
- Institute of Infectious Diseases, Guangzhou Eighth People's Hospital, Guangzhou Medical University, Guangzhou, 510440, Guangdong, China
| | - Zhiqiang Peng
- Guangdong Provincial Center for Disease Control and Prevention, Guangzhou, 511430, China
| | - Wenxin Hong
- Institute of Infectious Diseases, Guangzhou Eighth People's Hospital, Guangzhou Medical University, Guangzhou, 510440, Guangdong, China
| | - Xingyu Leng
- Institute of Infectious Diseases, Guangzhou Eighth People's Hospital, Guangzhou Medical University, Guangzhou, 510440, Guangdong, China
| | - Lei Luo
- Guangzhou Center for Disease Control and Prevention, Guangzhou, 510440, China
| | - Jone Jama Kpanda Ngobeh
- Department of Pathogen Biology, School of Public Health, Institute of Tropical Medicine, Southern Medical University; Guangdong Provincial Key Laboratory of Tropical Disease Research; Key Laboratory of Prevention and Control for Emerging Infectious Diseases of Guangdong Higher Institutes; Key Laboratory of Infectious Diseases Research in South China of Ministry of Education, Guangzhou, 510515, China
| | - Xiaoping Tang
- Institute of Infectious Diseases, Guangzhou Eighth People's Hospital, Guangzhou Medical University, Guangzhou, 510440, Guangdong, China
| | - Rangke Wu
- The School of Foreign Studies, Southern Medical University, Guangzhou, 510515, China
| | - Wei Zhao
- BSL-3 Laboratory(Guangdong), School of Public Health, Southern Medical University, Guangzhou, 510515, China
| | - Benyun Shi
- College of Computer and Information Engineering, Nanjing Tech University, Nanjing, 211816, China
| | - Jiming Liu
- Department of Computer Science, Hong Kong Baptist University, Hong Kong, 999077, China
| | - Zhicong Yang
- Guangzhou Center for Disease Control and Prevention, Guangzhou, 510440, China.
| | - Xiao-Guang Chen
- Department of Pathogen Biology, School of Public Health, Institute of Tropical Medicine, Southern Medical University; Guangdong Provincial Key Laboratory of Tropical Disease Research; Key Laboratory of Prevention and Control for Emerging Infectious Diseases of Guangdong Higher Institutes; Key Laboratory of Infectious Diseases Research in South China of Ministry of Education, Guangzhou, 510515, China.
| | - Xiaohong Zhou
- Department of Pathogen Biology, School of Public Health, Institute of Tropical Medicine, Southern Medical University; Guangdong Provincial Key Laboratory of Tropical Disease Research; Key Laboratory of Prevention and Control for Emerging Infectious Diseases of Guangdong Higher Institutes; Key Laboratory of Infectious Diseases Research in South China of Ministry of Education, Guangzhou, 510515, China.
| | - Fuchun Zhang
- Institute of Infectious Diseases, Guangzhou Eighth People's Hospital, Guangzhou Medical University, Guangzhou, 510440, Guangdong, China.
- Guangzhou Medical Research Institute of Infectious Diseases, Infectious Disease Center, Guangzhou Eighth People's Hospital, Guangzhou Medical University, Guangzhou, 510440, China.
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Tsai YY, Cheng D, Huang SW, Hung SJ, Wang YF, Lin YJ, Tsai HP, Chu JJH, Wang JR. The molecular epidemiology of a dengue virus outbreak in Taiwan: population wide versus infrapopulation mutation analysis. PLoS Negl Trop Dis 2024; 18:e0012268. [PMID: 38870242 PMCID: PMC11207123 DOI: 10.1371/journal.pntd.0012268] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Revised: 06/26/2024] [Accepted: 06/03/2024] [Indexed: 06/15/2024] Open
Abstract
Dengue virus (DENV) causes approximately 390 million dengue infections worldwide every year. There were 22,777 reported DENV infections in Tainan, Taiwan in 2015. In this study, we sequenced the C-prM-E genes from 45 DENV 2015 strains, and phylogenetic analysis based on C-prM-E genes revealed that all strains were classified as DENV serotype 2 Cosmopolitan genotype. Sequence analysis comparing different DENV-2 genotypes and Cosmopolitan DENV-2 sequences prior to 2015 showed a clade replacement event in the DENV-2 Cosmopolitan genotype. Additionally, a major substitution C-A314G (K73R) was found in the capsid region which may have contributed to the clade replacement event. Reverse genetics virus rgC-A314G (K73R) showed slower replication in BHK-21 and C6/36 cells compared to wildtype virus, as well as a decrease in NS1 production in BHK-21-infected cells. After a series of passaging, the C-A314G (K73R) mutation reverted to wildtype and was thus considered to be unstable. Next generation sequencing (NGS) of three sera collected from a single DENV2-infected patient at 1-, 2-, and 5-days post-admission was employed to examine the genetic diversity over-time and mutations that may work in conjunction with C-A314G (K73R). Results showed that the number of haplotypes decreased with time in the DENV-infected patient. On the fifth day after admission, two new haplotypes emerged, and a single non-synonymous NS4A-L115I mutation was identified. Therefore, we have identified a persistent mutation C-A314G (K73R) in all of the DENV-2 isolates, and during the course of an infection, a single new non-synonymous mutation in the NS4A region appears in the virus population within a single host. The C-A314G (K73R) thus may have played a role in the DENV-2 2015 outbreak while the NS4A-L115I may be advantageous during DENV infection within the host.
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Affiliation(s)
- You-Yuan Tsai
- Department of Medical Laboratory Science and Biotechnology, College of Medicine, National Cheng Kung University, Tainan, Taiwan
- Department of Pathology, National Cheng Kung University Hospital, Tainan, Taiwan
| | - Dayna Cheng
- Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Sheng-Wen Huang
- National Mosquito-Borne Diseases Control Research Center, National Health Research Institutes, Tainan, Taiwan
| | - Su-Jhen Hung
- National Mosquito-Borne Diseases Control Research Center, National Health Research Institutes, Tainan, Taiwan
| | - Ya-Fang Wang
- National Mosquito-Borne Diseases Control Research Center, National Health Research Institutes, Tainan, Taiwan
| | - Yih-Jyh Lin
- Division of General Surgery, Department of Surgery, College of Medicine, National Cheng Kung University Hospital, Tainan, Taiwan
| | - Huey-Pin Tsai
- Department of Medical Laboratory Science and Biotechnology, College of Medicine, National Cheng Kung University, Tainan, Taiwan
- Department of Pathology, National Cheng Kung University Hospital, Tainan, Taiwan
| | - Justin Jang Hann Chu
- Infectious Diseases Translational Research Program and Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Jen-Ren Wang
- Department of Medical Laboratory Science and Biotechnology, College of Medicine, National Cheng Kung University, Tainan, Taiwan
- Department of Pathology, National Cheng Kung University Hospital, Tainan, Taiwan
- Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan
- Center of Infectious Disease and Signaling Research, National Cheng Kung University, Tainan, Taiwan
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Guo X, Li L, Ren W, Hu M, Li Z, Zeng S, Liu X, Wang Y, Xie T, Yin Q, Wei Y, Luo L, Shi B, Wang C, Wu R, Yang Z, Chen XG, Zhou X. Modelling the dynamic basic reproduction number of dengue based on MOI of Aedes albopictus derived from a multi-site field investigation in Guangzhou, a subtropical region. Parasit Vectors 2024; 17:79. [PMID: 38383475 DOI: 10.1186/s13071-024-06121-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Accepted: 01/03/2024] [Indexed: 02/23/2024] Open
Abstract
BACKGROUND More than half of the global population lives in areas at risk of dengue (DENV) transmission. Developing an efficient risk prediction system can help curb dengue outbreaks, but multiple variables, including mosquito-based surveillance indicators, still constrain our understanding. Mosquito or oviposition positive index (MOI) has been utilized in field surveillance to monitor the wild population density of Aedes albopictus in Guangzhou since 2005. METHODS Based on the mosquito surveillance data using Mosq-ovitrap collection and human landing collection (HLC) launched at 12 sites in Guangzhou from 2015 to 2017, we established a MOI-based model of the basic dengue reproduction number (R0) using the classical Ross-Macdonald framework combined with a linear mixed-effects model. RESULTS During the survey period, the mean MOI and adult mosquito density index (ADI) using HLC for Ae. albopictus were 12.96 ± 17.78 and 16.79 ± 55.92, respectively. The R0 estimated from the daily ADI (ADID) showed a significant seasonal variation. A 10-unit increase in MOI was associated with 1.08-fold (95% CI 1.05, 1.11) ADID and an increase of 0.14 (95% CI 0.05, 0.23) in the logarithmic transformation of R0. MOI-based R0 of dengue varied by month and average monthly temperature. During the active period of Ae. albopictus from April to November in Guangzhou region, a high risk of dengue outbreak was predicted by the MOI-based R0 model, especially from August to October, with the predicted R0 > 1. Meanwhile, from December to March, the estimates of MOI-based R0 were < 1. CONCLUSIONS The present study enriched our knowledge about mosquito-based surveillance indicators and indicated that the MOI of Ae. albopictus could be valuable for application in estimating the R0 of dengue using a statistical model. The MOI-based R0 model prediction of the risk of dengue transmission varied by month and temperature in Guangzhou. Our findings lay a foundation for further development of a complex efficient dengue risk prediction system.
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Affiliation(s)
- Xiang Guo
- Department of Pathogen Biology, Institute of Tropical Medicine, Key Laboratory of Prevention and Control for Emerging Infectious Diseases of Guangdong Higher Institutes, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, 510515, China
| | - Li Li
- State Key Laboratory of Organ Failure Research, Department of Biostatistics, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, China
| | - Wenwen Ren
- Department of Pathogen Biology, Institute of Tropical Medicine, Key Laboratory of Prevention and Control for Emerging Infectious Diseases of Guangdong Higher Institutes, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, 510515, China
| | - Minling Hu
- Department of Pathogen Biology, Institute of Tropical Medicine, Key Laboratory of Prevention and Control for Emerging Infectious Diseases of Guangdong Higher Institutes, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, 510515, China
| | - Ziyao Li
- Department of Pathogen Biology, Institute of Tropical Medicine, Key Laboratory of Prevention and Control for Emerging Infectious Diseases of Guangdong Higher Institutes, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, 510515, China
| | - Shu Zeng
- Department of Pathogen Biology, Institute of Tropical Medicine, Key Laboratory of Prevention and Control for Emerging Infectious Diseases of Guangdong Higher Institutes, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, 510515, China
| | - Xiaohua Liu
- Department of Pathogen Biology, Institute of Tropical Medicine, Key Laboratory of Prevention and Control for Emerging Infectious Diseases of Guangdong Higher Institutes, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, 510515, China
| | - Yuji Wang
- Department of Pathogen Biology, Institute of Tropical Medicine, Key Laboratory of Prevention and Control for Emerging Infectious Diseases of Guangdong Higher Institutes, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, 510515, China
| | - Tian Xie
- Department of Pathogen Biology, Institute of Tropical Medicine, Key Laboratory of Prevention and Control for Emerging Infectious Diseases of Guangdong Higher Institutes, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, 510515, China
| | - Qingqing Yin
- Department of Pathogen Biology, Institute of Tropical Medicine, Key Laboratory of Prevention and Control for Emerging Infectious Diseases of Guangdong Higher Institutes, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, 510515, China
| | - Yuehong Wei
- Guangzhou Center for Disease Control and Prevention, Guangzhou, China
| | - Lei Luo
- Guangzhou Center for Disease Control and Prevention, Guangzhou, China
| | - Benyun Shi
- School of Computer Science and Technology, Nanjing Tech University, Nanjing, China
| | - Chunmei Wang
- Department of Pathogen Biology, Institute of Tropical Medicine, Key Laboratory of Prevention and Control for Emerging Infectious Diseases of Guangdong Higher Institutes, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, 510515, China
| | - Rangke Wu
- The School of Foreign Studies, Southern Medical University, Guangzhou, China
| | - Zhicong Yang
- Guangzhou Center for Disease Control and Prevention, Guangzhou, China
| | - Xiao-Guang Chen
- Department of Pathogen Biology, Institute of Tropical Medicine, Key Laboratory of Prevention and Control for Emerging Infectious Diseases of Guangdong Higher Institutes, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, 510515, China
| | - Xiaohong Zhou
- Department of Pathogen Biology, Institute of Tropical Medicine, Key Laboratory of Prevention and Control for Emerging Infectious Diseases of Guangdong Higher Institutes, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, 510515, China.
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Meng JX, Hu QM, Zhang LM, Li N, He YW, Yang ZX, Sun Y, Wang JL. Isolation and Genetic Evolution of Dengue Virus from the 2019 Outbreak in Xishuangbanna, Yunnan Province, China. Vector Borne Zoonotic Dis 2023. [PMID: 37184906 DOI: 10.1089/vbz.2022.0091] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/16/2023] Open
Abstract
Background: Dengue virus (DENV) can be divided into four serotypes-DENV-1, DENV-2, DENV-3, and DENV-4. In humans, infection leads to dengue fever (DF), dengue hemorrhagic fever, and dengue shock syndrome, both widely prevalent in tropical and subtropical regions. In 2019, a severe outbreak of DF occurred in Xishuangbanna, Yunnan province. Objective: To investigate the etiology and genotype of the causative agents of this severe dengue outbreak in Xishuangbanna. Methods: Between October and November 2019, the sera of patients clinically diagnosed with DF were collected in the first People's Hospital of Xishuangbanna. RNA was extracted from the sera and amplified by RT-PCR with flavivirus primers. Flavivirus-positive sera were then used to inoculate Aedes albopictus cells (C6/36); viral RNA was extracted from these cells, amplified, and sequenced with DENV E gene-specific primers. Sequence splicing and nucleotide homology genetic evolution analysis were carried out by biological software (DNAStar). Unique mutations in the E genes of isolated DENV were analyzed by SWISS-MODEL and PyMOL. Results: Of the 60 samples collected from DF patients, 39 tested positively with flavivirus primers. The DENV was isolated from 25 of the 39 positive seras, of which 20 showed cytopathic effects (CPE) and 5 were no CPE. In these 25 isolated nucleic acids, 21 strains of DENV-1, 3 strains of DENV-2, and 1 strain of DENV-3 were identified according to the sequence of E protein. In the four unique mutations (D52, Y149, L312, T386), D52 and Y149 in the E protein of DENV-1 were predicted to be exposed on the surface of the prefusion conformation. Conclusion: The 2019 outbreak of DF in Xishuangbanna area of Yunnan Province consists of at least three serotypes of DENV-1, DENV-2, and DENV-3, and the sources of these virus strains are of mixed and complicated origin.
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Affiliation(s)
- Jin-Xin Meng
- Yunnan Tropical and Subtropical Animal Virus Disease Laboratory, Yunnan Animal Science and Veterinary Institute, Kunming, China
| | - Qiu-Ming Hu
- People's Hospital of Jinghong City, Jinghong, China
| | - Li-Ming Zhang
- Tsinghua-Peking Center for Life Sciences, School of Medicine, Tsinghua University, Beijing, China
| | - Nan Li
- Yunnan Tropical and Subtropical Animal Virus Disease Laboratory, Yunnan Animal Science and Veterinary Institute, Kunming, China
| | - Yu-Wen He
- Yunnan Tropical and Subtropical Animal Virus Disease Laboratory, Yunnan Animal Science and Veterinary Institute, Kunming, China
| | - Zhen-Xing Yang
- Yunnan Tropical and Subtropical Animal Virus Disease Laboratory, Yunnan Animal Science and Veterinary Institute, Kunming, China
| | - Yi Sun
- The First People's Hospital of Yunnan Province, Kunming, China
| | - Jing-Lin Wang
- Yunnan Tropical and Subtropical Animal Virus Disease Laboratory, Yunnan Animal Science and Veterinary Institute, Kunming, China
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Gao Y, Yang L, Chen Y, Liu P, Zhou Y, Chen X, Gu J. Aal-circRNA-407 regulates ovarian development of Aedes albopictus, a major arbovirus vector, via the miR-9a-5p/Foxl axis. PLoS Pathog 2023; 19:e1011374. [PMID: 37146060 DOI: 10.1371/journal.ppat.1011374] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Revised: 05/17/2023] [Accepted: 04/19/2023] [Indexed: 05/07/2023] Open
Abstract
Aedes albopictus shows a rapid global expansion and dramatic vectorial capacity for various arboviruses, thus posing a severe threat to global health. Although many noncoding RNAs have been confirmed to play functional roles in various biological processes in Ae. albopictus, the roles of circRNA remain a mystery. In the present study, we first performed high-throughput circRNA sequencing in Ae. albopictus. Then, we identified a cysteine desulfurase (CsdA) superfamily gene-originated circRNA, named aal-circRNA-407, which was the third most abundant circRNA in adult females and displayed a fat body highly expressed manifestation and blood feeding-dependent onset. SiRNA-mediated knockdown of circRNA-407 resulted in a decrease in the number of developing follicles and a reduction in follicle size post blood meal. Furthermore, we demonstrated that circRNA-407 can act as a sponge of aal-miR-9a-5p to promote the expression of its target gene Foxl and eventually regulate ovarian development. Our study is the first to report a functional circRNA in mosquitoes, expanding our current understanding of important biological roles in mosquitoes and providing an alternative genetic strategy for mosquito control.
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Affiliation(s)
- Yonghui Gao
- Guangdong Provincial Key Laboratory of Tropical Disease Research, Department of Pathogen Biology, School of Public Health, Southern Medical University, Guangzhou, Guangdong, China
| | - Lu Yang
- Guangdong Provincial Key Laboratory of Tropical Disease Research, Department of Pathogen Biology, School of Public Health, Southern Medical University, Guangzhou, Guangdong, China
| | - Yulan Chen
- Guangdong Provincial Key Laboratory of Tropical Disease Research, Department of Pathogen Biology, School of Public Health, Southern Medical University, Guangzhou, Guangdong, China
| | - Peiwen Liu
- Guangdong Provincial Key Laboratory of Tropical Disease Research, Department of Pathogen Biology, School of Public Health, Southern Medical University, Guangzhou, Guangdong, China
| | - Ying Zhou
- Guangdong Provincial Key Laboratory of Tropical Disease Research, Department of Pathogen Biology, School of Public Health, Southern Medical University, Guangzhou, Guangdong, China
| | - Xiaoguang Chen
- Guangdong Provincial Key Laboratory of Tropical Disease Research, Department of Pathogen Biology, School of Public Health, Southern Medical University, Guangzhou, Guangdong, China
| | - Jinbao Gu
- Guangdong Provincial Key Laboratory of Tropical Disease Research, Department of Pathogen Biology, School of Public Health, Southern Medical University, Guangzhou, Guangdong, China
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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. [PMID: 37138627 PMCID: PMC10149964 DOI: 10.3389/fmicb.2023.1156176] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Accepted: 03/29/2023] [Indexed: 05/05/2023] Open
Abstract
Introduction In 2019, China experienced massive dengue outbreaks with high incidence and expanded outbreak areas. The study aims to depict dengue's epidemiology and evolutionary dynamics in China and explore the possible origin of these outbreaks. Methods Records of confirmed dengue cases in 2019 were obtained from the China Notifiable Disease Surveillance System. The sequences of complete envelope gene detected from the outbreak provinces in China in 2019 were retrieved from GenBank. Maximum Likelihood trees were constructed to genotype the viruses. The median-joining network was used to visualize fine-scale genetic relationships. Four methods were used to estimate the selective pressure. Results A total of 22,688 dengue cases were reported, 71.4% of which were indigenous cases and 28.6% were imported cases (including from abroad and from other domestic provinces). The abroad cases were predominantly imported from Southeast Asia countries (94.6%), with Cambodia (3,234 cases, 58.9%), and Myanmar (1,097 cases, 20.0%) ranked as the top two. A total of 11 provinces with dengue outbreaks were identified in the central-south of China, of which Yunnan and Guangdong provinces had the highest number of imported and indigenous cases. The primary source of imported cases in Yunnan was from Myanmar, while in the other ten provinces, the majority of imported cases were from Cambodia. Guangdong, Yunnan and Guangxi provinces were China's primary sources of domestically imported cases. Phylogenetic analysis of the viruses in outbreak provinces revealed three genotypes: (I, IV, and V) in DENV 1, Cosmopolitan and Asian I genotypes in DENV 2, and two genotypes (I and III) in DENV 3. Some genotypes concurrently circulated in different outbreak provinces. Most of the viruses were clustered with those from Southeast Asia. Haplotype network analysis showed that Southeast Asia, possibly Cambodia and Thailand, was the respective origin of the viruses in clade 1 and 4 for DENV 1. Positive selection was detected at codon 386 in clade 1. Conclusion Dengue importation from abroad, especially from Southeast Asia, resulted in the dengue epidemic in China in 2019. Domestic transmission between provinces and positive selection on virus evolution may contribute to the massive dengue outbreaks.
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Affiliation(s)
- Shaowei Sang
- Clinical Epidemiology Unit, Qilu Hospital of Shandong University, Jinan, Shandong, China
- Clinical Research Center of Shandong University, Jinan, Shandong, China
- *Correspondence: Shaowei Sang,
| | - Yujuan Yue
- State Key Laboratory of Infectious Disease Prevention and Control, Chinese Center for Disease Control and Prevention, National Institute for Communicable, Disease Control and Prevention, Beijing, China
| | - Yiguan Wang
- Institute of Ecology and Evolution, University of Edinburgh, Edinburgh, United Kingdom
| | - Xiangwei Zhang
- Department of Thoracic Surgery, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, Shandong, China
- Xiangwei Zhang,
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Wang R, Wang X, Zhang L, Feng G, Liu M, Zeng Y, Xie Z. The epidemiology and disease burden of children hospitalized for viral infections within the family Flaviviridae in China: A national cross-sectional study. PLoS Negl Trop Dis 2022; 16:e0010562. [PMID: 35788743 PMCID: PMC9286261 DOI: 10.1371/journal.pntd.0010562] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Revised: 07/15/2022] [Accepted: 06/03/2022] [Indexed: 11/24/2022] Open
Abstract
Background Viruses of the family Flaviviridae, including Japanese encephalitis virus (JEV), dengue virus (DENV), yellow fever virus (YFV) and hepatitis C virus (HCV), are widely distributed worldwide. JEV, DENV and YFV belong to the genus Flavivirus, whereas HCV belongs to the genus Hepacivirus. Children’s symptoms are usually severe. As a result, rates of hospitalization due to infection with these viruses are high. The epidemiology and disease burden of hospitalized children have rarely been described in detail to date. The objective of this study was to report the general epidemiological characteristics, clinical phenotype, length of stay (LOS), burden of disease, and potential risk factors for hospitalized children infected with JEV, DENV, YFV, or HCV in Chinese pediatric hospitals. Methodology A cross-sectional study of epidemiology and disease burden of children hospitalized for Flaviviridae virus infections between December 2015 and December 2020 in China was performed. Face sheets of discharge medical records (FSMRs) were collected from 27 tertiary children’s hospitals in the Futang Research Center of Pediatric Development and aggregated into FUTang Update medical REcords (FUTURE). Information on sociodemographic variables, clinical phenotype, and LOS as well as economic burden was included in FSMRs and compared using appropriate statistical tests. Findings The study described 490 children aged 0–15 years hospitalized for infections with Flaviviridae viruses. Japanese encephalitis (JE) cases are the highest, accounting for 92.65% of the total hospitalization cases caused by Flaviviridae virus infection. The incidence of JE peaked from July to October with a profile of a high proportion of severe cases (68.06%) and low mortality (0.44%). Rural children had a significantly higher incidence than urban children (91.63%). Most hospitalized dengue cases were reported in 2019 when dengue outbreaks occurred in many provinces of China, although only 14 dengue cases were collected during the study period. Yellow fever (YF) is still an imported disease in China. The hospitalizations for children with hepatitis C (HC) were not high, and mild chronic HC was the main clinical phenotype of patients. Among the four viral infections, JE had the highest disease burden (LOS and expenditure) for hospitalized children. Conclusion First, the present study reveals that JE remains the most serious disease due to Flaviviridae virus infection and threatens children’s health in China. Many pediatric patients have severe illnesses, but their mortality rate is lower, suggesting that existing treatment is effective. Both JEV vaccination and infection control of rural children should represent a focus of study. Second, although the dual risks of indigenous epidemics and imports of DENV still exist, the prevalence of DENV in children is generally manageable. Third, YFV currently shows no evidence of an epidemic in China. Finally, the proportion of children with chronic hepatitis C (CHC) is relatively large among hospitalized children diagnosed with HCV. Thus, early and effective intervention should be offered to children infected with HCV to ease the burden of CHC on public health. We performed a general epidemiological and disease burden assessment of 490 hospitalized children infected with any virus from the family Flaviviridae [Japanese encephalitis virus (JEV), dengue virus (DENV), yellow fever virus (YFV) and hepatitis C virus (HCV)] from December 2015 to December 2020 with confirmed clinical presentation and laboratory results. Our study found that hospitalization for Japanese encephalitis (JE) predominated in children who lived in rural areas, and the infection was rate was considerably higher in summer and autumn (July–October) compared with other months. In addition, children hospitalized with JE have the largest share of disease burden. However, the overall low rate of hospitalization and mortality of children shows that China’s JE prevention and control policies remain effective. However, the prevention, control and surveillance of JEV in rural areas should not be neglected. Dengue and yellow fever have not yet caused serious public health concerns among children in China, but the spatial and temporal distributions of viral infection must be assessed to be alert to the indigenous spread of imported cases. CHC is a refractory phenotype of HCV infection in children; thus, early screening and intervention are encouraged given the insidious appearance of symptoms in the early stages after HCV infection. These findings can help to understand the epidemic status of viruses classified in the family Flaviviridae in children and the disease burden of hospitalized children, which is conducive to precise prevention and control, optimization of the allocation of resources, and the formulation of more reasonable and effective policies.
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Affiliation(s)
- Ran Wang
- Beijing Key Laboratory of Pediatric Respiratory Infectious Diseases, Key Laboratory of Major Diseases in Children, Ministry of Education, National Clinical Research Center for Respiratory Diseases, Research Unit of Critical Infection in Children, Chinese Academy of Medical Sciences, 2019RU016, Laboratory of Infection and Virology, Beijing Pediatric Research Institute, Beijing Children’s Hospital, Capital Medical University, National Center for Children’s Health, Beijing, China
| | - Xinyu Wang
- Big Data Center, Beijing Children’s Hospital, Capital Medical University, National Center for Children’s Health, Beijing, China
| | - Linlin Zhang
- Beijing Key Laboratory of Pediatric Respiratory Infectious Diseases, Key Laboratory of Major Diseases in Children, Ministry of Education, National Clinical Research Center for Respiratory Diseases, Research Unit of Critical Infection in Children, Chinese Academy of Medical Sciences, 2019RU016, Laboratory of Infection and Virology, Beijing Pediatric Research Institute, Beijing Children’s Hospital, Capital Medical University, National Center for Children’s Health, Beijing, China
| | - Guoshuang Feng
- Big Data Center, Beijing Children’s Hospital, Capital Medical University, National Center for Children’s Health, Beijing, China
| | - Mengjia Liu
- Beijing Key Laboratory of Pediatric Respiratory Infectious Diseases, Key Laboratory of Major Diseases in Children, Ministry of Education, National Clinical Research Center for Respiratory Diseases, Research Unit of Critical Infection in Children, Chinese Academy of Medical Sciences, 2019RU016, Laboratory of Infection and Virology, Beijing Pediatric Research Institute, Beijing Children’s Hospital, Capital Medical University, National Center for Children’s Health, Beijing, China
| | - Yueping Zeng
- Medical Record Management Office, Beijing Children’s Hospital, Capital Medical University, National Center for Children’s Health, Beijing, China
| | - Zhengde Xie
- Beijing Key Laboratory of Pediatric Respiratory Infectious Diseases, Key Laboratory of Major Diseases in Children, Ministry of Education, National Clinical Research Center for Respiratory Diseases, Research Unit of Critical Infection in Children, Chinese Academy of Medical Sciences, 2019RU016, Laboratory of Infection and Virology, Beijing Pediatric Research Institute, Beijing Children’s Hospital, Capital Medical University, National Center for Children’s Health, Beijing, China
- * E-mail:
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Survivorship-Reducing Effect of Propylene Glycol on Vector Mosquito Populations and Its Potential Use in Attractive Toxic Sugar Baits. INSECTS 2022; 13:insects13070595. [PMID: 35886771 PMCID: PMC9324135 DOI: 10.3390/insects13070595] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Revised: 06/24/2022] [Accepted: 06/26/2022] [Indexed: 02/05/2023]
Abstract
Simple Summary Mosquitoes (Diptera: Culicidae) spread disease and pose a significant risk to public health around the world. While there are currently many control measures available, many are typically unsafe for humans and other animals, and they are becoming less effective against mosquitoes. We tested a compound called propylene glycol (1,2 propanediol) for its toxicity to three species of mosquitoes that serve as vectors of human pathogens. Propylene glycol is a compound that the FDA has designated as generally regarded as safe (GRAS) for human consumption, meaning it is approved for use in everyday household products. Through a series of assays in which we fed mosquitoes propylene glycol, we found that this compound is highly toxic to all three mosquito species examined and can drastically reduce the survivorship of laboratory populations. Our results suggest that propylene glycol could be a safe and effective substance to be used in the context of attractive toxic sugar baits (ATSBs) as a means of controlling mosquitoes near human habitations. Abstract Arthropod control mechanisms are a vital part of public health measures around the world as many insect species serve as vectors for devastating human diseases. Aedes aegypti (Linnaeus, 1762) is a widely distributed, medically important mosquito species that transmits viruses such as yellow fever, Dengue, and Zika. Many traditional control mechanisms have become less effective due to insecticide resistance or exhibit unwanted off-target effects, and, consequently, there is a need for novel solutions. The use of attractive toxic sugar baits (ATSBs) has increased in recent years, though the toxic elements are often harmful to humans and other vertebrates. Therefore, we are investigating propylene glycol, a substance that is generally regarded as safe (GRAS) for human consumption. Using a series of feeding assays, we found that propylene glycol is highly toxic to Ae. aegypti adults and a single day of exposure significantly reduces the survivorship of test populations compared with controls. The effects are more pronounced in males, drastically reducing their survivorship after one day of consumption. Additionally, the consumption of propylene glycol reduced the survivorship of two prominent disease vectors: Aedes albopictus (Skuse, 1894) and Culex pipiens (Linnaeus, 1758). These findings indicate that propylene glycol could be used as a safe and effective alternative to pesticides in an ATSB system.
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Dengue Fever in Mainland China, 2005-2020: A Descriptive Analysis of Dengue Cases and Aedes Data. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:ijerph19073910. [PMID: 35409612 PMCID: PMC8997546 DOI: 10.3390/ijerph19073910] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/07/2022] [Revised: 03/07/2022] [Accepted: 03/15/2022] [Indexed: 12/10/2022]
Abstract
Dengue fever occurs throughout mainland China, except in the Tibet Autonomous Region. During 2005–2020, there were 12,701 imported cases and 81,653 indigenous cases recorded. The indigenous cases were mainly clustered in Guangdong (74.0%) and Yunnan provinces (13.7%). Indigenous dengue fever is a seasonal illness in mainland China, manifesting predominantly in summer and autumn. Indigenous dengue fever cases tend to peak every 5years and have shown a substantial increase during the period 2005–2020. During the study period, indigenous dengue fever occurred more than ten times in each of the seven counties of Guangdong Province. Indigenous dengue fever has spread from low to high latitudes; that is, from the southwestern, southern, and southeastern areas to the central and northern regions, and from border ports and cities to rural areas. Aedes aegypti has become widespread in Yunnan Province but has diminished in Guangxi, Guangdong, and Hainan provinces in recent years. Aedes albopictus is distributed throughout mainland China, spanning 25 provinces and municipalities. To maintain effective public health prevention and control, it is important to monitor dengue occurrence, provide dengue classification guidance, and ensure sustainable vector management of Aedes.
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