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Marcombe S, Doeurk B, Thammavong P, Veseli T, Heafield C, Mills MA, Kako S, Prado MF, Thomson S, Millett S, Hill T, Kentsley I, Davies S, Pathiraja G, Daniels B, Browne L, Nyamukanga M, Harvey J, Rubinstein L, Townsend C, Allen Z, Davey-Spence C, Hupi A, Jones AK, Boyer S. Metabolic Resistance and Not Voltage-Gated Sodium Channel Gene Mutation Is Associated with Pyrethroid Resistance of Aedes albopictus (Skuse, 1894) from Cambodia. INSECTS 2024; 15:358. [PMID: 38786914 PMCID: PMC11122440 DOI: 10.3390/insects15050358] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2024] [Revised: 05/08/2024] [Accepted: 05/10/2024] [Indexed: 05/25/2024]
Abstract
(1) Background: In Cambodia, Aedes albopictus is an important vector of the dengue virus. Vector control using insecticides is a major strategy implemented in managing mosquito-borne diseases. Resistance, however, threatens to undermine the use of insecticides. In this study, we present the levels of insecticide resistance of Ae. albopictus in Cambodia and the mechanisms involved. (2) Methods: Two Ae. albopictus populations were collected from the capital, Phnom Penh city, and from rural Pailin province. Adults were tested with diagnostic doses of malathion (0.8%), deltamethrin (0.03%), permethrin (0.25%), and DDT (4%) using WHO tube assays. Synergist assays using piperonyl butoxide (PBO) were implemented before the pyrethroid assays to detect the potential involvement of metabolic resistance mechanisms. Adult female mosquitoes collected from Phnom Penh and Pailin were tested for voltage-gated sodium channel (VGSC) kdr (knockdown resistance) mutations commonly found in Aedes sp.-resistant populations throughout Asia (S989P, V1016G, and F1534C), as well as for other mutations (V410L, L982W, A1007G, I1011M, T1520I, and D1763Y). (3) Results: The two populations showed resistance against all the insecticides tested (<90% mortality). The use of PBO (an inhibitor of P450s) strongly restored the efficacy of deltamethrin and permethrin against the two resistant populations. Sequences of regions of the vgsc gene showed a lack of kdr mutations known to be associated with pyrethroid resistance. However, four novel non-synonymous mutations (L412P/S, C983S, Q1554STOP, and R1718L) and twenty-nine synonymous mutations were detected. It remains to be determined whether these mutations contribute to pyrethroid resistance. (4) Conclusions: Pyrethroid resistance is occurring in two Ae. albopictus populations originating from urban and rural areas of Cambodia. The resistance is likely due to metabolic resistance specifically involving P450s monooxygenases. The levels of resistance against different insecticide classes are a cause for concern in Cambodia. Alternative tools and insecticides for controlling dengue vectors should be used to minimize disease prevalence in the country.
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Affiliation(s)
- Sébastien Marcombe
- Medical Entomology and Vector-borne Diseases Laboratory, Institut Pasteur du Laos, Ministry of Health, Vientiane P.O. Box 3560, Laos; (S.M.); (P.T.)
- Vector Control Consulting—South East Asia Sole Co., Ltd., Vientiane P.O. Box 3463, Laos
| | - Bros Doeurk
- Medical and Veterinary Entomology Unit, Institut Pasteur du Cambodge, 5 Boulevard Monivong, Phnom Penh P.O. Box 983, Cambodia; (B.D.); (S.B.)
| | - Phoutmany Thammavong
- Medical Entomology and Vector-borne Diseases Laboratory, Institut Pasteur du Laos, Ministry of Health, Vientiane P.O. Box 3560, Laos; (S.M.); (P.T.)
| | - Tuba Veseli
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, Oxford OX3 0BP, UK; (T.V.); (C.H.); (M.-A.M.); (S.K.); (M.F.P.); (S.T.); (S.M.); (T.H.); (I.K.); (S.D.); (G.P.); (B.D.); (L.B.); (M.N.); (J.H.); (L.R.); (C.T.); (Z.A.); (C.D.-S.); (A.H.)
- Independent Researcher, Derby DE65 5NX, UK
| | - Christian Heafield
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, Oxford OX3 0BP, UK; (T.V.); (C.H.); (M.-A.M.); (S.K.); (M.F.P.); (S.T.); (S.M.); (T.H.); (I.K.); (S.D.); (G.P.); (B.D.); (L.B.); (M.N.); (J.H.); (L.R.); (C.T.); (Z.A.); (C.D.-S.); (A.H.)
- Independent Researcher, Oxford OX14 2RN, UK
| | - Molly-Ann Mills
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, Oxford OX3 0BP, UK; (T.V.); (C.H.); (M.-A.M.); (S.K.); (M.F.P.); (S.T.); (S.M.); (T.H.); (I.K.); (S.D.); (G.P.); (B.D.); (L.B.); (M.N.); (J.H.); (L.R.); (C.T.); (Z.A.); (C.D.-S.); (A.H.)
- UK Health Security Agency, Porton Down, Salisbury SP4 0JG, UK
| | - Sedra Kako
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, Oxford OX3 0BP, UK; (T.V.); (C.H.); (M.-A.M.); (S.K.); (M.F.P.); (S.T.); (S.M.); (T.H.); (I.K.); (S.D.); (G.P.); (B.D.); (L.B.); (M.N.); (J.H.); (L.R.); (C.T.); (Z.A.); (C.D.-S.); (A.H.)
| | - Marcelly Ferreira Prado
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, Oxford OX3 0BP, UK; (T.V.); (C.H.); (M.-A.M.); (S.K.); (M.F.P.); (S.T.); (S.M.); (T.H.); (I.K.); (S.D.); (G.P.); (B.D.); (L.B.); (M.N.); (J.H.); (L.R.); (C.T.); (Z.A.); (C.D.-S.); (A.H.)
- Oxford University Hospitals, Churchill Hospital, Genetics Laboratories, Old Rd, Headington, Oxford OX3 7LE, UK
| | - Shakira Thomson
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, Oxford OX3 0BP, UK; (T.V.); (C.H.); (M.-A.M.); (S.K.); (M.F.P.); (S.T.); (S.M.); (T.H.); (I.K.); (S.D.); (G.P.); (B.D.); (L.B.); (M.N.); (J.H.); (L.R.); (C.T.); (Z.A.); (C.D.-S.); (A.H.)
- Independent Researcher, Burnham-On-Sea TA8 1AZ, UK
| | - Saffron Millett
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, Oxford OX3 0BP, UK; (T.V.); (C.H.); (M.-A.M.); (S.K.); (M.F.P.); (S.T.); (S.M.); (T.H.); (I.K.); (S.D.); (G.P.); (B.D.); (L.B.); (M.N.); (J.H.); (L.R.); (C.T.); (Z.A.); (C.D.-S.); (A.H.)
| | - Timothy Hill
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, Oxford OX3 0BP, UK; (T.V.); (C.H.); (M.-A.M.); (S.K.); (M.F.P.); (S.T.); (S.M.); (T.H.); (I.K.); (S.D.); (G.P.); (B.D.); (L.B.); (M.N.); (J.H.); (L.R.); (C.T.); (Z.A.); (C.D.-S.); (A.H.)
- London School of Hygiene & Tropical Medicine, Keppel Street, London WC1E 7HT, UK
| | - Imogen Kentsley
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, Oxford OX3 0BP, UK; (T.V.); (C.H.); (M.-A.M.); (S.K.); (M.F.P.); (S.T.); (S.M.); (T.H.); (I.K.); (S.D.); (G.P.); (B.D.); (L.B.); (M.N.); (J.H.); (L.R.); (C.T.); (Z.A.); (C.D.-S.); (A.H.)
- Independent Researcher, Brighton BN8 4HR, UK
| | - Shereena Davies
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, Oxford OX3 0BP, UK; (T.V.); (C.H.); (M.-A.M.); (S.K.); (M.F.P.); (S.T.); (S.M.); (T.H.); (I.K.); (S.D.); (G.P.); (B.D.); (L.B.); (M.N.); (J.H.); (L.R.); (C.T.); (Z.A.); (C.D.-S.); (A.H.)
- Independent Researcher, Shrewsbury SY1 4YP, UK
| | - Geethika Pathiraja
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, Oxford OX3 0BP, UK; (T.V.); (C.H.); (M.-A.M.); (S.K.); (M.F.P.); (S.T.); (S.M.); (T.H.); (I.K.); (S.D.); (G.P.); (B.D.); (L.B.); (M.N.); (J.H.); (L.R.); (C.T.); (Z.A.); (C.D.-S.); (A.H.)
- Independent Researcher, Wallingford OX10 7EA, UK
| | - Ben Daniels
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, Oxford OX3 0BP, UK; (T.V.); (C.H.); (M.-A.M.); (S.K.); (M.F.P.); (S.T.); (S.M.); (T.H.); (I.K.); (S.D.); (G.P.); (B.D.); (L.B.); (M.N.); (J.H.); (L.R.); (C.T.); (Z.A.); (C.D.-S.); (A.H.)
- Syngenta, Jealott’s Hill International Research Centre, Bracknell RG42 6EY, Berkshire, UK
| | - Lucianna Browne
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, Oxford OX3 0BP, UK; (T.V.); (C.H.); (M.-A.M.); (S.K.); (M.F.P.); (S.T.); (S.M.); (T.H.); (I.K.); (S.D.); (G.P.); (B.D.); (L.B.); (M.N.); (J.H.); (L.R.); (C.T.); (Z.A.); (C.D.-S.); (A.H.)
- Independent Researcher, Reading RG31 4SE, UK
| | - Miranda Nyamukanga
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, Oxford OX3 0BP, UK; (T.V.); (C.H.); (M.-A.M.); (S.K.); (M.F.P.); (S.T.); (S.M.); (T.H.); (I.K.); (S.D.); (G.P.); (B.D.); (L.B.); (M.N.); (J.H.); (L.R.); (C.T.); (Z.A.); (C.D.-S.); (A.H.)
- Wythenshawe Hospital, Southmoor Rd, Wythenshawe M23 9LT, Manchester, UK
| | - Jess Harvey
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, Oxford OX3 0BP, UK; (T.V.); (C.H.); (M.-A.M.); (S.K.); (M.F.P.); (S.T.); (S.M.); (T.H.); (I.K.); (S.D.); (G.P.); (B.D.); (L.B.); (M.N.); (J.H.); (L.R.); (C.T.); (Z.A.); (C.D.-S.); (A.H.)
- Oxford Nanopore Technologies plc, Unit 3, Genesis Building, Library Avenue, Harwell, Didcot OX11 0SG, Oxfordshire, UK
| | - Lyranne Rubinstein
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, Oxford OX3 0BP, UK; (T.V.); (C.H.); (M.-A.M.); (S.K.); (M.F.P.); (S.T.); (S.M.); (T.H.); (I.K.); (S.D.); (G.P.); (B.D.); (L.B.); (M.N.); (J.H.); (L.R.); (C.T.); (Z.A.); (C.D.-S.); (A.H.)
- Independent Researcher, 69009 Lyon, France
| | - Chloe Townsend
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, Oxford OX3 0BP, UK; (T.V.); (C.H.); (M.-A.M.); (S.K.); (M.F.P.); (S.T.); (S.M.); (T.H.); (I.K.); (S.D.); (G.P.); (B.D.); (L.B.); (M.N.); (J.H.); (L.R.); (C.T.); (Z.A.); (C.D.-S.); (A.H.)
| | - Zack Allen
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, Oxford OX3 0BP, UK; (T.V.); (C.H.); (M.-A.M.); (S.K.); (M.F.P.); (S.T.); (S.M.); (T.H.); (I.K.); (S.D.); (G.P.); (B.D.); (L.B.); (M.N.); (J.H.); (L.R.); (C.T.); (Z.A.); (C.D.-S.); (A.H.)
| | - Christopher Davey-Spence
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, Oxford OX3 0BP, UK; (T.V.); (C.H.); (M.-A.M.); (S.K.); (M.F.P.); (S.T.); (S.M.); (T.H.); (I.K.); (S.D.); (G.P.); (B.D.); (L.B.); (M.N.); (J.H.); (L.R.); (C.T.); (Z.A.); (C.D.-S.); (A.H.)
| | - Adina Hupi
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, Oxford OX3 0BP, UK; (T.V.); (C.H.); (M.-A.M.); (S.K.); (M.F.P.); (S.T.); (S.M.); (T.H.); (I.K.); (S.D.); (G.P.); (B.D.); (L.B.); (M.N.); (J.H.); (L.R.); (C.T.); (Z.A.); (C.D.-S.); (A.H.)
- Independent Researcher, Oxford OX3 8HP, UK
| | - Andrew K. Jones
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, Oxford OX3 0BP, UK; (T.V.); (C.H.); (M.-A.M.); (S.K.); (M.F.P.); (S.T.); (S.M.); (T.H.); (I.K.); (S.D.); (G.P.); (B.D.); (L.B.); (M.N.); (J.H.); (L.R.); (C.T.); (Z.A.); (C.D.-S.); (A.H.)
| | - Sebastien Boyer
- Medical and Veterinary Entomology Unit, Institut Pasteur du Cambodge, 5 Boulevard Monivong, Phnom Penh P.O. Box 983, Cambodia; (B.D.); (S.B.)
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Liao JR, Tu WC, Chiu MC, Kuo MH, Cheng HC, Chan CC, Dai SM. Joint influence of architectural and spatiotemporal factors on the presence of Aedes aegypti in urban environments. PEST MANAGEMENT SCIENCE 2023; 79:4367-4375. [PMID: 37384574 DOI: 10.1002/ps.7634] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Revised: 06/22/2023] [Accepted: 06/29/2023] [Indexed: 07/01/2023]
Abstract
BACKGROUND Urbanization has led to the proliferation of high-rise buildings, which have substantially influenced the distribution of dengue vectors, such as Aedes aegypti (L.). However, knowledge gaps exist regarding the individual and combined effects of architectural and spatiotemporal factors on dengue vector. This study investigated the interrelationship between Ae. aegypti presence, building architectural features, and spatiotemporal factors in urban environments. RESULTS The mosquito Ae. aegypti presence varied by location and seasons, being higher in outdoor environments than in indoor environments. Lingya (Kaohsiung City, Taiwan) had the highest mosquito numbers, particularly in basement and first floor areas. Ae. aegypti was found on multiple floors within buildings, and their presence was greater in summer and autumn. The XGBoost model revealed that height within a building, temperature, humidity, resident density, and rainfall were key factors influencing mosquito presence, whereas openness had a relatively minor impact. CONCLUSION To effectively address the problems caused by urbanization, the three-dimensional distribution of Ae. aegypti, including their spatial distribution across heights and areas within the urban environment, must be considered. By incorporating these multiple factors, this approach provides valuable insights for those responsible for urban planning and disease management strategies. Understanding the interplay between architectural features, environmental conditions, and the presence of Ae. aegypti is essential for developing targeted interventions and mitigating the adverse impacts of urbanization on public health. © 2023 Society of Chemical Industry.
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Affiliation(s)
- Jhih-Rong Liao
- Department of Entomology, National Chung Hsing University, Taichung City, Taiwan
- Systematic Zoology Laboratory, Department of Biological Sciences, Tokyo Metropolitan University, Hachioji City, Tokyo, Japan
| | - Wu-Chun Tu
- Department of Entomology, National Chung Hsing University, Taichung City, Taiwan
- School of Life Sciences and Technology, Institut Teknologi Bandung, Bandung, West Java, Indonesia
| | - Ming-Chih Chiu
- Department of Entomology, National Chung Hsing University, Taichung City, Taiwan
- Center for Marine Environmental Studies (CMES), Ehime University, Matsuyama City, Ehime, Japan
| | - Mei-Hwa Kuo
- Department of Entomology, National Chung Hsing University, Taichung City, Taiwan
| | - Hui-Ching Cheng
- National Mosquito-Borne Diseases Control Research Center, National Health Research Institutes, Kaohsiung City, Taiwan
| | - Chia-Chun Chan
- Department of Entomology, National Chung Hsing University, Taichung City, Taiwan
| | - Shu-Mei Dai
- Department of Entomology, National Chung Hsing University, Taichung City, Taiwan
- Center for Dengue Fever Control and Research, Kaohsiung Medical University, Kaohsiung City, Taiwan
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Khan MB, Yang ZS, Lin CY, Hsu MC, Urbina AN, Assavalapsakul W, Wang WH, Chen YH, Wang SF. Dengue overview: An updated systemic review. J Infect Public Health 2023; 16:1625-1642. [PMID: 37595484 DOI: 10.1016/j.jiph.2023.08.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 07/24/2023] [Accepted: 08/01/2023] [Indexed: 08/20/2023] Open
Abstract
Dengue is caused by the dengue virus (DENVs) infection and clinical manifestations include dengue fever (DF), dengue hemorrhagic fever (DHF), or dengue shock syndrome (DSS). Due to a lack of antiviral drugs and effective vaccines, several therapeutic and control strategies have been proposed. A systemic literature review was conducted according to PRISMA guidelines to select proper references to give an overview of DENV infection. Results indicate that understanding the virus characteristics and epidemiology are essential to gain the basic and clinical knowledge as well as dengue disseminated pattern and status. Different factors and mechanisms are thought to be involved in the presentation of DHF and DSS, including antibody-dependent enhancement, immune dysregulation, viral virulence, host genetic susceptibility, and preexisting dengue antibodies. This study suggests that dissecting pathogenesis and risk factors as well as developing different types of therapeutic and control strategies against DENV infection are urgently needed.
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Affiliation(s)
- Muhammad Bilal Khan
- Center for Tropical Medicine and Infectious Disease Research, Kaohsiung Medical University, Kaohsiung 80708, Taiwan; Department of Medical Laboratory Science and Biotechnology, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
| | - Zih-Syuan Yang
- Center for Tropical Medicine and Infectious Disease Research, Kaohsiung Medical University, Kaohsiung 80708, Taiwan; Department of Medical Laboratory Science and Biotechnology, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
| | - Chih-Yen Lin
- Center for Tropical Medicine and Infectious Disease Research, Kaohsiung Medical University, Kaohsiung 80708, Taiwan; Department of Medical Laboratory Science and Biotechnology, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
| | - Ming-Cheng Hsu
- Center for Tropical Medicine and Infectious Disease Research, Kaohsiung Medical University, Kaohsiung 80708, Taiwan; Department of Medical Laboratory Science and Biotechnology, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
| | - Aspiro Nayim Urbina
- Center for Tropical Medicine and Infectious Disease Research, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
| | - Wanchai Assavalapsakul
- Department of Microbiology, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand
| | - Wen-Hung Wang
- School of Medicine, College of Medicine, National Sun Yat-Sen University, Kaohsiung 804201, Taiwan
| | - Yen-Hsu Chen
- Center for Tropical Medicine and Infectious Disease Research, Kaohsiung Medical University, Kaohsiung 80708, Taiwan; School of Medicine, College of Medicine, National Sun Yat-Sen University, Kaohsiung 804201, Taiwan; Division of Infectious Disease, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung 80708, Taiwan
| | - Sheng-Fan Wang
- Center for Tropical Medicine and Infectious Disease Research, Kaohsiung Medical University, Kaohsiung 80708, Taiwan; Department of Medical Laboratory Science and Biotechnology, Kaohsiung Medical University, Kaohsiung 80708, Taiwan; Department of Medical Research, Kaohsiung Medical University Hospital, Kaohsiung 80708, Taiwan.
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Weather-Based Prediction Models for the Prevalence of Dengue Vectors Aedes aegypti and Ae. albopictus. J Trop Med 2022; 2022:4494660. [PMID: 36605885 PMCID: PMC9810403 DOI: 10.1155/2022/4494660] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2022] [Revised: 11/26/2022] [Accepted: 11/28/2022] [Indexed: 12/29/2022] Open
Abstract
Dengue is an important vector-borne disease transmitted by the mosquitoes Aedes aegypti and Ae. albopictus. In the absence of an effective vaccine, vector control has become the key intervention tool in controlling the disease. Vector densities are significantly affected by the changing weather patterns of a region. The present study was conducted in three selected localities, i.e., urban Bandaranayakapura, semiurban Galgamuwa, and rural Buluwala in the Kurunegala district of Sri Lanka to assess spatial and temporal distribution of dengue vector mosquitoes and to predict vector prevalence with respect to changing weather parameters. Monthly ovitrap surveys and larval surveys were conducted from January to December 2019 and continued further in the urban area up to December 2021. Aedes aegypti was found moderately in the urban area and to a lesser extent in semiurban but not in the rural area. Aedes albopictus had the preference for rural over urban areas. Aedes aegypti preferred indoor breeding, while Ae. albopictus preferred both indoor and outdoor. For Ae. albopictus, ovitrap index (OVI), premise index (PI), container index (CI), and Breteau index (BI) correlated with both the rainfall (RF) and relative humidity (RH) of the urban site. Correlations were stronger between OVI and RH and also between BI and RF. Linear regression analysis was fitted, and a prediction model was developed using BI and RF with no lag period (R 2 (sq) = 86.3%; F = 53.12; R 2 (pred) = 63.12%; model: Log10 (BI) = 0.153 + 0.286 ∗ Log10 (RF); RMSE = 1.49). Another prediction model was developed using OVI and RH with one month lag period (R 2 (sq) = 70.21%; F = 57.23; model: OVI predicted = 15.1 + 0.528 ∗ Lag 1 month RH; RMSE = 2.01). These two models can be used to monitor the population dynamics of Ae. albopictus in urban settings to predict possible dengue outbreaks.
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Dengue Meteorological Determinants during Epidemic and Non-Epidemic Periods in Taiwan. Trop Med Infect Dis 2022; 7:tropicalmed7120408. [PMID: 36548663 PMCID: PMC9785930 DOI: 10.3390/tropicalmed7120408] [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: 11/07/2022] [Revised: 11/25/2022] [Accepted: 11/27/2022] [Indexed: 12/05/2022] Open
Abstract
The identification of the key factors influencing dengue occurrence is critical for a successful response to the outbreak. It was interesting to consider possible differences in meteorological factors affecting dengue incidence during epidemic and non-epidemic periods. In this study, the overall correlation between weekly dengue incidence rates and meteorological variables were conducted in southern Taiwan (Tainan and Kaohsiung cities) from 2007 to 2017. The lagged-time Poisson regression analysis based on generalized estimating equation (GEE) was also performed. This study found that the best-fitting Poisson models with the smallest QICu values to characterize the relationships between dengue fever cases and meteorological factors in Tainan (QICu = −8.49 × 10−3) and Kaohsiung (−3116.30) for epidemic periods, respectively. During dengue epidemics, the maximum temperature with 2-month lag (β = 0.8400, p < 0.001) and minimum temperature with 5-month lag (0.3832, p < 0.001). During non-epidemic periods, the minimum temperature with 3-month lag (0.1737, p < 0.001) and mean temperature with 2-month lag (2.6743, p < 0.001) had a positive effect on dengue incidence in Tainan and Kaohsiung, respectively.
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Trájer AJ. Aedes aegypti in the Mediterranean container ports at the time of climate change: A time bomb on the mosquito vector map of Europe. Heliyon 2021; 7:e07981. [PMID: 34568601 PMCID: PMC8449062 DOI: 10.1016/j.heliyon.2021.e07981] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Revised: 08/10/2021] [Accepted: 09/08/2021] [Indexed: 10/27/2022] Open
Abstract
In the past, Aedes aegypti was present in Southern Europe. Although the mosquito was eradicated from the Mediterranean region, its regional ecotype survived the second half of the 20th century in the eastern Black Sea area. The aim of the study was to model the changes in the altering climatic suitability, ontogenetic development time and the survival rate of Aedes aegypti from first-stage larvae to adulthood in Southern Europe. The modelled present climatic suitability patterns of the mosquito show that large areas of the lower altitude Mediterranean regions, including the coastal areas of the Balkan Peninsula, South France, and large regions of the Apennines and the Iberian Peninsulas could be suitable for Ae. aegypti. The future (2041-2060 and 2061-2080) projections predict the potential northward shift of the northern occurrence of the species in the circum-Mediterranean and Black Sea areas. Both, the potential development time, and survival rate of Ae. aegypti in the late 19th and the early 20th century could be like in the present times along the Mediterranean coast. The current climatic conditions cannot explain the absence of the mosquito in wide areas of the Mediterranean and sub-Mediterranean ecoregions. The future models predict the notable increase in the development time and survival rate of the mosquito in the southern and central regions of Europe. In general, the container ports of the Alboran, Balearic, and Aegean seas seem to be the most suitable sites for the re-colonization of the mosquito, and such northern parts of the Mediterranean Sea like the Gulf of Lion, the Ligurian, and Adriatic Seas are in less extent.
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Affiliation(s)
- Attila J. Trájer
- Sustainability Solutions Research Lab, University of Pannonia, Egyetem utca 10, H-8200, Veszprém, Hungary
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Detection of Aedes (Stegomyia) albopictus (Skuse) in ovitraps of Mérida city, México. ACTA ACUST UNITED AC 2021; 41:153-160. [PMID: 33761198 PMCID: PMC8055587 DOI: 10.7705/biomedica.5525] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Indexed: 11/21/2022]
Abstract
Introduction: The vector-borne diseases program in México has an established network of ovitraps for entomological surveillance of Aedes spp. In response to reports of Aedes albopictus in the periphery of Mérida, the state capital of Yucatán, the Ministry of Health increased the specificity of this surveillance.
Objective: To describe the presence and distribution of Ae. albopictus in Mérida and its relative abundance compared to Aedes aegypti in ovitraps of the vector control program.
Materials and methods: During October, 2019, 91 ovitraps were randomly selected from 31 neighborhoods of Mérida. Mosquitoes were reared at the insectary of the Collaborative Unit for Entomological Bioassays of the Autonomous University of Yucatán from eggs collected in the field. Relative abundance was determined for adult individuals of each identified species and neighborhood.
Results: 32 % of the neighborhoods were positive for Ae. albopictus and 100 % for Ae. aegypti. A total of 28 adults of Ae. albopictus (10 females and 18 males) were obtained from ovitraps. No correlation was observed between the abundance of Ae. aegypti and Ae. albopictus for both adults and females (p>0.05) at the neighborhood level.
Conclusions: The results confirm that Ae. albopictus coexisted with Ae. aegypti in Mérida at the time of the study. The low relative abundance suggests that Ae. albopictus was in the initial phase of invasion.
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Life as a Vector of Dengue Virus: The Antioxidant Strategy of Mosquito Cells to Survive Viral Infection. Antioxidants (Basel) 2021; 10:antiox10030395. [PMID: 33807863 PMCID: PMC8000470 DOI: 10.3390/antiox10030395] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Revised: 02/27/2021] [Accepted: 03/01/2021] [Indexed: 12/15/2022] Open
Abstract
Dengue fever is a mosquito-borne viral disease of increasing global importance. The disease has caused heavy burdens due to frequent outbreaks in tropical and subtropical areas of the world. The dengue virus (DENV) is generally transmitted between human hosts via the bite of a mosquito vector, primarily Aedes aegypti and Ae. albopictus as a minor species. It is known that the virus needs to alternately infect mosquito and human cells. DENV-induced cell death is relevant to the pathogenesis in humans as infected cells undergo apoptosis. In contrast, mosquito cells mostly survive the infection; this allows infected mosquitoes to remain healthy enough to serve as an efficient vector in nature. Overexpression of antioxidant genes such as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione S-transferase (GST), glutaredoxin (Grx), thioredoxin (Trx), and protein disulfide isomerase (PDI) have been detected in DENV2-infected mosquito cells. Additional antioxidants, including GST, eukaryotic translation initiation factor 5A (eIF5a), and p53 isoform 2 (p53-2), and perhaps some others, are also involved in creating an intracellular environment suitable for cell replication and viral infection. Antiapoptotic effects involving inhibitor of apoptosis (IAP) upregulation and subsequent elevation of caspase-9 and caspase-3 activities also play crucial roles in the ability of mosquito cells to survive DENV infection. This article focused on the effects of intracellular responses in mosquito cells to infection primarily by DENVs. It may provide more information to better understand virus/cell interactions that can possibly elucidate the evolutionary pathway that led to the mosquito becoming a vector.
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Maquart PO, Fontenille D, Boyer S. Recent and massive invasion of Aedes (Stegomyia) albopictus (Skuse, 1894) in Phnom Penh, Cambodia. Parasit Vectors 2021; 14:113. [PMID: 33602318 PMCID: PMC7890877 DOI: 10.1186/s13071-021-04633-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Accepted: 02/08/2021] [Indexed: 11/17/2022] Open
Affiliation(s)
- P O Maquart
- Medical and Veterinary Entomology Unit, Institut Pasteur du Cambodge 5, Blvd. Monivong, BP 983, Phnom Penh, 12201, Cambodia.
| | - D Fontenille
- Medical and Veterinary Entomology Unit, Institut Pasteur du Cambodge 5, Blvd. Monivong, BP 983, Phnom Penh, 12201, Cambodia.,MIVEGEC, Université de Montpellier, IRD (Institut de Recherche et du Développement), CNRS, 911 Avenue Agropolis, 34394, Montpellier, France
| | - S Boyer
- Medical and Veterinary Entomology Unit, Institut Pasteur du Cambodge 5, Blvd. Monivong, BP 983, Phnom Penh, 12201, Cambodia
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10
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Lee YH, Hsieh YC, Chen CJ, Lin TY, Huang YC. Retrospective Seroepidemiology study of dengue virus infection in Taiwan. BMC Infect Dis 2021; 21:96. [PMID: 33478432 PMCID: PMC7818053 DOI: 10.1186/s12879-021-05809-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Accepted: 01/15/2021] [Indexed: 01/26/2023] Open
Abstract
Background Dengue virus infection has been an important and serious public health concern in Taiwan, where local outbreaks of dengue fever occurred almost every year. To our knowledge, no nationwide investigation has been carried out to determine the actual extent of infection in the general population. Methods A total of 1308 random serum samples were collected from the general population in Taiwan in 2010. The antibody-captured enzyme-linked immunosorbent assays were used to detect DENV-specific IgM and IgG. Demographics data were used for risk analysis. Results The weighted overall seroprevalence was 1.96% for anti-DENV IgM, and 3.4% for anti-DENV IgG, respectively. A significant rise of DENV IgG seropositive rate had been noted since late adulthood stage, from 1.1% at the age group of 50–59 years to 7.6% at the age group of 60–69 years. For people aged over 70 years, the seropositive rate reached 19%. Age, nationality, and regions of residency were associated with the IgG seropositivity. There was no statistically significant difference in seroprevalence of anti-Dengue IgM, indicating recent infection, among univariate predictors we proposed, including gender, age, residency, nationality, and household size. Conclusions Our results indicated that the majority of population in Taiwan born after 1940 is naive to dengue virus and the prevalence of IgG antibody against dengue virus rises with age. Nationality, and regions of residency are associated with the exposure of population to infection by dengue viruses. Further studies are needed to realize the current situation of seroprevalence of dengue fever in Taiwan.
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Affiliation(s)
- Ying-Hsuan Lee
- Chang Gung University College of Medicine, Gueishan, Taoyuan, Taiwan
| | - Yu-Chia Hsieh
- Chang Gung University College of Medicine, Gueishan, Taoyuan, Taiwan.,Department of Pediatrics, Division of Pediatric Infectious Diseases, Chang Gung Memorial Hospital, No. 5, Fu-Shin Street, Gueishan, 333, Taoyuan, Taiwan
| | - Chih-Jung Chen
- Chang Gung University College of Medicine, Gueishan, Taoyuan, Taiwan.,Department of Pediatrics, Division of Pediatric Infectious Diseases, Chang Gung Memorial Hospital, No. 5, Fu-Shin Street, Gueishan, 333, Taoyuan, Taiwan
| | - Tzou-Yien Lin
- Chang Gung University College of Medicine, Gueishan, Taoyuan, Taiwan.,Department of Pediatrics, Division of Pediatric Infectious Diseases, Chang Gung Memorial Hospital, No. 5, Fu-Shin Street, Gueishan, 333, Taoyuan, Taiwan
| | - Yhu-Chering Huang
- Chang Gung University College of Medicine, Gueishan, Taoyuan, Taiwan. .,Department of Pediatrics, Division of Pediatric Infectious Diseases, Chang Gung Memorial Hospital, No. 5, Fu-Shin Street, Gueishan, 333, Taoyuan, Taiwan.
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11
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Kubacki J, Flacio E, Qi W, Guidi V, Tonolla M, Fraefel C. Viral Metagenomic Analysis of Aedes albopictus Mosquitos from Southern Switzerland. Viruses 2020; 12:v12090929. [PMID: 32846980 PMCID: PMC7552062 DOI: 10.3390/v12090929] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 08/17/2020] [Accepted: 08/19/2020] [Indexed: 02/07/2023] Open
Abstract
A metagenomic study was performed on 498 female and 40 male Aedes albopictus mosquitos collected in August and September 2019 in Ticino, a region in southern Switzerland, to address the question regarding the risk of the local transmission of zoonotic viruses. A total of 13 viruses from seven different virus families and several unclassified viral taxa were identified. Reads of insect-specific flaviviruses were present in all pools, and a complete genome of aedes flavivirus was assembled and phylogenetically analysed. The most abundant virus was Wenzhou sobemo-like virus, assembled from 1.3 × 105 to 3.6 × 106 reads in each pool. In a pool of male mosquitos, a complete genome of aedes Iflavi-like virus was detected and phylogenetically analysed. Most importantly, genomes of human pathogenic viruses were not found. This is the first study to determine the virome of Ae. albopictus from Switzerland and forms a baseline for future longitudinal investigations concerning the potential role of Ae. albopictus as a vector of clinically relevant viruses.
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Affiliation(s)
- Jakub Kubacki
- Institute of Virology, University of Zürich, CH-8057 Zürich, Switzerland
- Correspondence: (J.K.); (C.F.)
| | - Eleonora Flacio
- Laboratory of Applied Microbiology, Department for Environment Constructions and Design, University of Applied Sciences and Arts of Southern Switzerland, CH-6500 Manno, Switzerland; (E.F.); (V.G.); (M.T.)
| | - Weihong Qi
- Functional Genomics Center Zurich, CH-8057 Zürich, Switzerland;
| | - Valeria Guidi
- Laboratory of Applied Microbiology, Department for Environment Constructions and Design, University of Applied Sciences and Arts of Southern Switzerland, CH-6500 Manno, Switzerland; (E.F.); (V.G.); (M.T.)
| | - Mauro Tonolla
- Laboratory of Applied Microbiology, Department for Environment Constructions and Design, University of Applied Sciences and Arts of Southern Switzerland, CH-6500 Manno, Switzerland; (E.F.); (V.G.); (M.T.)
| | - Cornel Fraefel
- Institute of Virology, University of Zürich, CH-8057 Zürich, Switzerland
- Correspondence: (J.K.); (C.F.)
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12
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Cell-to-Cell Spread of Dengue Viral RNA in Mosquito Cells. BIOMED RESEARCH INTERNATIONAL 2020; 2020:2452409. [PMID: 32685452 PMCID: PMC7335394 DOI: 10.1155/2020/2452409] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/28/2020] [Accepted: 06/08/2020] [Indexed: 12/26/2022]
Abstract
Dengue virus (DENV) is an important mosquito-borne arbovirus that is particularly prevalent in tropical and subtropical areas of the world. The virus is generally ingested with a blood meal, replicates in host tissues, and disseminates into salivary glands for transmission to the next host. Membrane-bound vacuoles carrying DENV particles have been documented in mosquito cells and play a role in the cell-to-cell transmission of DENV2. C189 is one member of the tetraspanin family and generally increases its expression as one component of the vacuoles (C189-VCs) within C6/36 cells infected with DENV2. In the present study, we have further demonstrated via sucrose gradient centrifugation as well as magnetic immune isolation (MI) that the RNA of DENV2 was eventually carried by C189-VCs. In addition, viral RNA was shown to spread from donor to recipient cells in a coculture assay even when 20 mM NH4Cl was added to inhibit virus replication in the culture. In an alternate assay using the transwell system, viral RNA was only detected in recipient cells in the absence of 40 mM NH4Cl, suggesting that cell-cell contact is required for the intercellular spread of DENV2. In turn, the formation of viral synapse (VS) derived from aggregates of viral particles was frequently observed at sites of cell contact. Taken together, the formation of C189-VCs in C6/36 cells is induced by DENV2 infection, which may serve as a vehicle for transferring virions and also viral RNA to neighboring cells by cell-to-cell transmission after cell-cell contact. This finding provides insight into the understanding of viral spread between mosquito cells. It may also elucidate the benign persistent infection in mosquito cells and efficient dissemination of DENV infection within a mosquito vector.
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Chen YA, Lai YT, Wu KC, Yen TY, Chen CY, Tsai KH. Using UPLC-MS/MS to Evaluate the Dissemination of Pyriproxyfen by Aedes Mosquitoes to Combat Cryptic Larval Habitats after Source Reduction in Kaohsiung in Southern Taiwan. INSECTS 2020; 11:insects11040251. [PMID: 32316283 PMCID: PMC7240724 DOI: 10.3390/insects11040251] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Revised: 04/10/2020] [Accepted: 04/15/2020] [Indexed: 12/16/2022]
Abstract
The policy regarding mosquito control strategies in Taiwan is based on integrated vector management (IVM). The major approach is source reduction via collaboration by both residents and governments. However, small and cryptic habitats of dengue vectors are hard to find and eliminate in urban communities. Therefore, this study evaluated a complementary approach that targeted cryptic habitats by utilizing mosquitoes themselves as vehicles to transfer an insect growth regulator, pyriproxyfen (PPF), to their breeding sites; the amount of PPF in breeding water was determined with ultra-performance liquid chromatography coupled with tandem mass spectrometry (UPLC–MS/MS). A bioassay conducted by introducing ten late-instar larvae into PPF solution was performed to assess emergence inhibition (EI). PPF was found at 0.56 ± 0.04 ng in 25 mL of water by dissemination via ten Aedes aegypti mosquitoes exposed to 0.01% PPF, leading to 100% EI. After the community-level source reduction, a field trial in Kaohsiung in Southern Taiwan showed that 30.8–31.5% of cryptic ovitraps reached EI ≥ 50% one month after spraying 0.01% PPF in microhabitats favored by mosquitoes. IVM in parallel with residual spraying of PPF on resting surfaces of mosquitoes could serve as a simple and complementary approach to reduce cryptic larval sources in urban communities in Southern Taiwan.
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Affiliation(s)
- Ying-An Chen
- Institute of Environmental and Occupational Health Sciences, College of Public Health, National Taiwan University, No. 17, Xuzhou Road, Taipei 100, Taiwan; (Y.-A.C.); (T.-Y.Y.); (C.-Y.C.)
| | - Yi-Ting Lai
- Master of Public Health Program, College of Public Health, National Taiwan University, No. 17, Xuzhou Road, Taipei 100, Taiwan;
| | - Kuo-Chih Wu
- National Mosquito-Borne Disease Control Research Center, National Health Research Institutes, No. 211, Zhongzheng 4th Rd., Qianjin Dist., Kaohsiung City 801, Taiwan;
| | - Tsai-Ying Yen
- Institute of Environmental and Occupational Health Sciences, College of Public Health, National Taiwan University, No. 17, Xuzhou Road, Taipei 100, Taiwan; (Y.-A.C.); (T.-Y.Y.); (C.-Y.C.)
| | - Chia-Yang Chen
- Institute of Environmental and Occupational Health Sciences, College of Public Health, National Taiwan University, No. 17, Xuzhou Road, Taipei 100, Taiwan; (Y.-A.C.); (T.-Y.Y.); (C.-Y.C.)
- Institute of Food Safety and Health, College of Public Health, National Taiwan University, No. 17, Xuzhou Road, Taipei 100, Taiwan
- Department of Public Health, College of Public Health, National Taiwan University, No. 17, Xuzhou Road, Taipei 100, Taiwan
| | - Kun-Hsien Tsai
- Institute of Environmental and Occupational Health Sciences, College of Public Health, National Taiwan University, No. 17, Xuzhou Road, Taipei 100, Taiwan; (Y.-A.C.); (T.-Y.Y.); (C.-Y.C.)
- Department of Public Health, College of Public Health, National Taiwan University, No. 17, Xuzhou Road, Taipei 100, Taiwan
- Department of Entomology, College of Bio-Resources and Agriculture, National Taiwan University, Insect Building: No. 27, Ln. 113, Sec. 4, Roosevelt Road, Taipei City 106, Taiwan
- Correspondence: ; Tel.: +886-2-33668103
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Wang WH, Urbina AN, Wu CC, Lin CY, Thitithanyanont A, Assavalapsakul W, Lu PL, Chen YH, Wang SF. An epidemiological survey of the current status of Zika and the immune interaction between dengue and Zika infection in Southern Taiwan. Int J Infect Dis 2020; 93:151-159. [PMID: 31982624 DOI: 10.1016/j.ijid.2020.01.031] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Revised: 01/13/2020] [Accepted: 01/19/2020] [Indexed: 02/06/2023] Open
Abstract
OBJECTIVES This study was performed to examine the current status of Zika and the effects of pre-existing dengue immunity on Zika virus (ZIKV) infection in Southern Taiwan. METHODS A phylogenetic tree was used to analyze the phylogeny of detected ZIKVs. Paired sera from dengue patients were collected for the determination of dengue and Zika infection. Plaque reduction neutralization tests (PRNT) and quantitative reverse transcription PCR (qRT-PCR) were used to determine the titers of neutralizing antibodies and viruses, respectively. An antibody-dependent enhancement (ADE) assay was used to evaluate the effect of anti-dengue antibodies on ZIKV infection. RESULTS Epidemiological data indicated the continuous importation of ZIKV infection from neighboring Zika epidemic countries into Taiwan. A total of 78 dengue patients were enrolled and 21 paired serum samples were obtained. PRNT90 results for the 21 samples identified eight cases of primary dengue infection and 13 cases of secondary dengue infection; two samples were positive for ZIKV (MR766). Results from the ADE assay indicated that convalescent sera from primary and secondary dengue infection patients displayed significant ADE of the ZIKV infection when compared to healthy controls (p < 0.05). CONCLUSIONS This study suggests that pre-existing dengue immunity facilitates ZIKV infection and that the continuous importation of ZIKV infection may pose a threat to indigenous Zika emergence in Southern Taiwan.
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Affiliation(s)
- Wen-Hung Wang
- Center for Tropical Medicine and Infectious Disease, Kaohsiung Medical University, Kaohsiung, 80708, Taiwan; Division of Infectious Disease, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, 80708, Taiwan
| | - Aspiro Nayim Urbina
- Center for Tropical Medicine and Infectious Disease, Kaohsiung Medical University, Kaohsiung, 80708, Taiwan; Program in Tropical Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, 80708, Taiwan
| | - Chia-Ching Wu
- Department of Medical Laboratory Science and Biotechnology, Kaohsiung Medical University, Kaohsiung, 80708, Taiwan
| | - Chih-Yen Lin
- Center for Tropical Medicine and Infectious Disease, Kaohsiung Medical University, Kaohsiung, 80708, Taiwan; Department of Laboratory Medicine, Kaohsiung Medical University Hospital, Kaohsiung, 80708, Taiwan
| | - Arunee Thitithanyanont
- Department of Microbiology, Faculty of Science, Mahidol University, Bangkok, 10400, Thailand
| | - Wanchai Assavalapsakul
- Department of Microbiology, Faculty of Science, Chulalongkorn University, Bangkok, 10330, Thailand
| | - Po-Liang Lu
- Division of Infectious Disease, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, 80708, Taiwan; Department of Laboratory Medicine, Kaohsiung Medical University Hospital, Kaohsiung, 80708, Taiwan
| | - Yen-Hsu Chen
- Center for Tropical Medicine and Infectious Disease, Kaohsiung Medical University, Kaohsiung, 80708, Taiwan; Division of Infectious Disease, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, 80708, Taiwan
| | - Sheng-Fan Wang
- Center for Tropical Medicine and Infectious Disease, Kaohsiung Medical University, Kaohsiung, 80708, Taiwan; Department of Laboratory Medicine, Kaohsiung Medical University Hospital, Kaohsiung, 80708, Taiwan; Department of Medical Laboratory Science and Biotechnology, Kaohsiung Medical University, Kaohsiung, 80708, Taiwan.
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15
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Chien YW, Ho TC, Huang PW, Ko NY, Ko WC, Perng GC. Low seroprevalence of Zika virus infection among adults in Southern Taiwan. BMC Infect Dis 2019; 19:884. [PMID: 31646973 PMCID: PMC6813068 DOI: 10.1186/s12879-019-4491-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2019] [Accepted: 09/23/2019] [Indexed: 12/22/2022] Open
Abstract
Background We recently conducted a serosurvey of newly arrived workers in Taiwan from four Southeast Asian countries which revealed that 1% of the migrant workers had laboratory-confirmed recent Zika virus (ZIKV) infection. Taiwan, where Aedes mosquitoes are prevalent, has a close relationship with Southeast Asian countries. Up to now, 21 imported cases of ZIKV infection have been reported in Taiwan, but there has been no confirmed indigenous case. The aim of this serosurvey was to assess whether there was unrecognized ZIKV infections in Taiwan. Methods A total of 212 serum samples collected in a cross-sectional seroepidemiologic study conducted during the end of the 2015 dengue epidemic in Tainan, Taiwan, were analyzed. Anti-ZIKV IgM and IgG were tested using commercial enzyme-linked immunosorbent assays (ELISAs). Plaque reduction neutralization tests (PRNTs) for ZIKV and four dengue virus (DENV) serotypes were performed for samples with positive anti-ZIKV antibodies. A confirmed case of ZIKV infection was defined by ZIKV PRNT90 titer ratio ≥ 4 compared to four DENV serotypes. Results The mean age of the 212 participants was 54.0 years (standard deviation 13.7 years), and female was predominant (67.0%). Anti-ZIKV IgM and IgG were detected in 0 (0%) and 9 (4.2%) of the 212 participants, respectively. For the 9 samples with anti-ZIKV IgG, only 1 sample had 4 times higher ZIKV PRNT90 titers compared to PRNT90 titers against four dengue virus serotypes; this individual denied having traveled abroad. Conclusions The results suggest that undetected indigenous ZIKV transmission might have occurred in Taiwan. The findings also suggest that the threat of epidemic transmission of ZIKV in Taiwan does exist due to extremely low-level of herd immunity. Our study also indicates that serological tests for ZIKV-specific IgG remain a big challenge due to cross-reactivity, even in dengue non-endemic countries.
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Affiliation(s)
- Yu-Wen Chien
- Department of Public Health, College of Medicine, National Cheng Kung University, Tainan, Taiwan.,Department of Occupational and Environmental Medicine, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Tzu-Chuan Ho
- Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Pei-Wen Huang
- Department of Public Health, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Nai-Ying Ko
- Department of Nursing, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Wen-Chien Ko
- Department of Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Guey Chuen Perng
- Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan. .,Department of Microbiology and Immunology, College of Medicine, National Cheng Kung University, No. 1, University Road, Tainan, 70101, Taiwan. .,Center of Infectious Disease and Signaling Research, National Cheng Kung University, Tainan, Taiwan.
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Azar SR, Weaver SC. Vector Competence: What Has Zika Virus Taught Us? Viruses 2019; 11:E867. [PMID: 31533267 PMCID: PMC6784050 DOI: 10.3390/v11090867] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2019] [Revised: 09/14/2019] [Accepted: 09/16/2019] [Indexed: 11/16/2022] Open
Abstract
The unprecedented outbreak of Zika virus (ZIKV) infection in the Americas from 2015 to 2017 prompted the publication of a large body of vector competence data in a relatively short period of time. Although differences in vector competence as a result of disparities in mosquito populations and viral strains are to be expected, the limited competence of many populations of the urban mosquito vector, Aedes aegypti, from the Americas (when its susceptibility is viewed relative to other circulating/reemerging mosquito-borne viruses such as dengue (DENV), yellow fever (YFV), and chikungunya viruses (CHIKV)) has proven a paradox for the field. This has been further complicated by the lack of standardization in the methodologies utilized in laboratory vector competence experiments, precluding meta-analyses of this large data set. As the calls for the standardization of such studies continue to grow in number, it is critical to examine the elements of vector competence experimental design. Herein, we review the various techniques and considerations intrinsic to vector competence studies, with respect to contemporary findings for ZIKV, as well as historical findings for other arboviruses, and discuss potential avenues of standardization going forward.
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Affiliation(s)
- Sasha R Azar
- Department of Microbiology and Immunology, University of Texas Medical Branch, 300 University Blvd, Galveston, TX 77555, USA.
- Institute for Translational Sciences, University of Texas Medical Branch, 300 University Blvd, Galveston, TX 77555, USA.
- Institute for Human Infections and Immunity, University of Texas Medical Branch, 300 University Blvd, Galveston, TX 77555, USA.
| | - Scott C Weaver
- Department of Microbiology and Immunology, University of Texas Medical Branch, 300 University Blvd, Galveston, TX 77555, USA.
- Institute for Translational Sciences, University of Texas Medical Branch, 300 University Blvd, Galveston, TX 77555, USA.
- Institute for Human Infections and Immunity, University of Texas Medical Branch, 300 University Blvd, Galveston, TX 77555, USA.
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Wang WH, Chen HJ, Lin CY, Assavalapsakul W, Wang SF. Imported dengue fever and climatic variation are important determinants facilitating dengue epidemics in Southern Taiwan. J Infect 2019; 80:121-142. [PMID: 31430483 DOI: 10.1016/j.jinf.2019.08.010] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2019] [Accepted: 08/13/2019] [Indexed: 11/17/2022]
Affiliation(s)
- Wen-Hung Wang
- Division of Infectious Disease, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung 80708, Taiwan; Center for Tropical Medicine and Infectious Disease, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
| | - Hsin-Jen Chen
- Institute of Public Health, School of Medicine, National Yang-Ming University, Taipei 11221, Taiwan
| | - Chih-Yen Lin
- Department of Medical Laboratory Science and Biotechnology, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
| | - Wanchai Assavalapsakul
- Department of Microbiology, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand
| | - Sheng-Fan Wang
- Center for Tropical Medicine and Infectious Disease, Kaohsiung Medical University, Kaohsiung 80708, Taiwan; Department of Medical Laboratory Science and Biotechnology, Kaohsiung Medical University, Kaohsiung 80708, Taiwan.
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18
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Paton RS, Bonsall MB. The ecological and epidemiological consequences of reproductive interference between the vectors Aedes aegypti and Aedes albopictus. J R Soc Interface 2019; 16:20190270. [PMID: 31362626 DOI: 10.1098/rsif.2019.0270] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Vector ecology is integral to understanding the transmission of vector-borne diseases, with processes such as reproduction and competition pivotal in determining vector presence and abundance. The arbovirus vectors Aedes aegypti and Aedes albopictus compete as larvae, but this mechanism is insufficient to explain patterns of coexistence and exclusion. Inviable interspecies matings-known as reproductive interference-is another candidate mechanism. Here, we analyse mathematical models of mosquito population dynamics and epidemiology which include two Aedes-specific features of reproductive interference. First, as these mosquitoes use hosts to find mates, reproductive interference will only occur if the same host is visited. Host choice will, in turn, be determined by behavioural responses to host availability. Second, females can become sterilized after mis-mating with heterospecifics. We find that a species with an affinity for a shared host will suffer more from reproductive interference than a less selective competitor. Costs from reproductive interference can be 'traded-off' against costs from larval competition, leading to competitive outcomes that are difficult to predict from empirical evidence. Sterilizations of a self-limiting species can counterintuitively lead to higher densities than a competitor suffering less sterilization. We identify that behavioural responses and reproductive interference mediate a concomitant relationship between vector ecological dynamics and epidemiology. Competitors with opposite behavioural responses can maintain disease where human hosts are rare, due to vector coexistence facilitated by a reduced cost from reproductive interference. Our work elucidates the relative roles of the competitive mechanisms governing Aedes populations and the associated epidemiological consequences.
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Affiliation(s)
- Robert S Paton
- Mathematical Ecology Research Group, Department of Zoology, University of Oxford, Oxford OX1 3PS, UK.,Balliol College, Broad Street, Oxford OX1 3BJ, UK
| | - Michael B Bonsall
- Mathematical Ecology Research Group, Department of Zoology, University of Oxford, Oxford OX1 3PS, UK.,St Peter's College, New Inn Hall Street, Oxford OX1 2DL, UK
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Chien YW, Huang HM, Ho TC, Tseng FC, Ko NY, Ko WC, Perng GC. Seroepidemiology of dengue virus infection among adults during the ending phase of a severe dengue epidemic in southern Taiwan, 2015. BMC Infect Dis 2019; 19:338. [PMID: 31014263 PMCID: PMC6480438 DOI: 10.1186/s12879-019-3946-y] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2018] [Accepted: 04/02/2019] [Indexed: 12/23/2022] Open
Abstract
BACKGROUND A severe dengue epidemic occurred in 2015 which resulted in over 22,000 laboratory-confirmed cases. A cross-sectional seroprevalence study was conducted during the ending phase of this epidemic to evaluate the true incidence of dengue virus (DENV) infection and the level of herd immunity. METHODS Adult residents in three administrative districts with high dengue incidence were recruited; workers in two districts with intermediate dengue incidence were also recruited for comparison. DENV-specific IgM and IgG were tested using commercial enzyme-linked immunosorbent assays. DENV RNA was detected using commercial quantitative real-time reverse transcriptase polymerase chain reaction assay. Univariate and multivariate logistic regressions were performed to identify risk factors for recent and past DENV infection. RESULTS The overall seroprevalence of anti-DENV IgM and IgG in 1391 participants was 6.8 and 17.4%, respectively. The risk of recent DENV infection increased with age, with the elderly having the highest risk of infection. Living in areas with high incidence of reported dengue cases and having family members being diagnosed with dengue in 2015 were also independent risk factors for recent DENV infection. One sample was found to have asymptomatic viremia with viral load as high as 105 PFU/ml. CONCLUSIONS Comparing the seroprevalence of anti-DENV IgM with the incidence of reported dengue cases in 2015, we estimated that 1 out of 3.7 dengue infections were reported to the surveillance system; widespread use of rapid diagnostic tests might contribute to this high reporting rate. The results also indicate that the overall herd immunity remains low and the current approved Dengvaxia® is not quite suitable for vaccination in Taiwan.
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Affiliation(s)
- Yu-Wen Chien
- Department of Public Health, College of Medicine, National Cheng Kung University, Tainan, Taiwan.,Department of Occupational and Environmental Medicine, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Hsiang-Min Huang
- Department of Public Health, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Tzu-Chuan Ho
- Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Fan-Chen Tseng
- Department of Nursing, National Taipei University of Nursing and Health Sciences, Taipei, Taiwan.,National Institute of Infectious Diseases and Vaccinology, National Health Research Institutes, Tainan, Taiwan
| | - Nai-Ying Ko
- Department of Nursing, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Wen-Chien Ko
- Department of Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Guey Chuen Perng
- Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan. .,Department of Microbiology and Immunology, College of Medicine, National Cheng Kung University, No. 1, University Road, Tainan, 70101, Taiwan. .,Center of Infectious Disease and Signaling Research, National Cheng Kung University, Tainan, Taiwan.
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20
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Chung HH, Cheng IC, Chen YC, Lin C, Tomita T, Teng HJ. Voltage-gated sodium channel intron polymorphism and four mutations comprise six haplotypes in an Aedes aegypti population in Taiwan. PLoS Negl Trop Dis 2019; 13:e0007291. [PMID: 30925149 PMCID: PMC6457567 DOI: 10.1371/journal.pntd.0007291] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Revised: 04/10/2019] [Accepted: 03/12/2019] [Indexed: 11/29/2022] Open
Abstract
Background Knockdown resistance (kdr) to dichlorodiphenyltrichloroethane (DDT) and pyrethroids is known to link amino acid substitutions in the voltage-gated sodium channel (VGSC) in Aedes aegypti. Dengue fever primarily transmitted by Ae. aegypti is an annual public health issue in Taiwan. Accordingly, pyrethroid insecticides have been heavily used for decades to control mosquito populations in the summer and autumn. In Taiwan, an Ae. aegypti population with two VGSC mutations, V1016G and D1763Y, was described previously. Methodology/Principal finding Aedes aegypti (G0) were collected in Tainan and Kaohsiung in southern Taiwan. The VGSC gene polymorphisms of the kdr mutations and the intron flanked by exons 20 and 21 were verified. The first generation offspring (G1) were used to measure the resistance level to cypermethrin, a pyrethroid insecticide currently used in Taiwan. In addition to V1016G and D1763Y, we describe two new mutations, S989P and F1534C, which have not been reported in Taiwan. Moreover, we also identify two types (groups A and B) of introns between exons 20 and 21. Intriguingly, the kdr mutations S989P, V1016G and D1763Y are strictly located on the haplotype harboring the group A intron, whereas F1534C links to the group B intron. When those data were taken together, we proposed the following six haplotypes for VGSC genes in Taiwan today: (i)S989-intron A-V1016-F1534-D1763, (ii)S989-intron A-V1016G-F1534-D1763, (iii)S989P-intron A-V1016G-F1534-D1763, (iv)S989-intron A-V1016G-F1534-D1763Y, (v)S989-intron B-V1016-F1534-D1763 and (vi)S989-intron B-V1016-F1534C-D1763. Triple heterozygous mutations of either S989P/V1016G/F1534C or V1016G/F1534C/D1763Y can be found in one single Ae. aegypti mosquito. The proportions of the VGSC mutations were relevant to cypermethrin resistance. Notably, the presence of S989P and V1016G in the population could be a helpful reference to predict the resistance level to cypermethrin. This is the first study to demonstrate the coexistence of four kdr mutations in a population of Ae. aegypti. Conclusions/Significance Four kdr mutations (S989P, V1016G, F1534C and D1763Y) and two intron forms (Group A and B) were commonly found in local Ae. aegypti populations in Taiwan. VGSC mutations of Aedes aegypti threaten vector control programs and have been brought to attention in dengue endemic areas. Taiwan has suffered dengue outbreaks, which usually begin from an imported case. Pyrethroid insecticides were used to kill infectious females and adults in the surrounding environment of each suspected case. In Taiwan, V1016G and F1763Y mutations of VGSC have been described previously. Here, we further describe two additional amino acid substitutions (S989P, F1534C) and two forms of the intron between exon 20 and 21. We also propose six haplotypes for VGSC genes in Taiwan today. In conclusion, four kdr mutations (S989P, V1016G, F1534C and D1763Y) and two intron forms (Group A and B) are commonly found in local Ae. aegypti populations in Taiwan.
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Affiliation(s)
- Han-Hsuan Chung
- Center for Diagnostics and Vaccine Development, Centers for Disease Control, Ministry of Health and Welfare, Taipei, Taiwan
| | - I-Cheng Cheng
- Center for Diagnostics and Vaccine Development, Centers for Disease Control, Ministry of Health and Welfare, Taipei, Taiwan
- National Mosquito-Borne Diseases Control Research Center, National Health Research Institutes, Miaoli, Taiwan
| | - Yen-Chi Chen
- Center for Diagnostics and Vaccine Development, Centers for Disease Control, Ministry of Health and Welfare, Taipei, Taiwan
- National Mosquito-Borne Diseases Control Research Center, National Health Research Institutes, Miaoli, Taiwan
| | - Cheo Lin
- Center for Diagnostics and Vaccine Development, Centers for Disease Control, Ministry of Health and Welfare, Taipei, Taiwan
| | - Takashi Tomita
- Department of Medical Entomology, National Institute of Infectious Diseases, Shinjuku-ku, Tokyo, Japan
| | - Hwa-Jen Teng
- Center for Diagnostics and Vaccine Development, Centers for Disease Control, Ministry of Health and Welfare, Taipei, Taiwan
- * E-mail:
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Hettiarachchige C, von Cavallar S, Lynar T, Hickson RI, Gambhir M. Risk prediction system for dengue transmission based on high resolution weather data. PLoS One 2018; 13:e0208203. [PMID: 30521550 PMCID: PMC6283552 DOI: 10.1371/journal.pone.0208203] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Accepted: 11/13/2018] [Indexed: 01/24/2023] Open
Abstract
BACKGROUND Dengue is the fastest spreading vector-borne viral disease, resulting in an estimated 390 million infections annually. Precise prediction of many attributes related to dengue is still a challenge due to the complex dynamics of the disease. Important attributes to predict include: the risk of and risk factors for an infection; infection severity; and the timing and magnitude of outbreaks. In this work, we build a model for predicting the risk of dengue transmission using high-resolution weather data. The level of dengue transmission risk depends on the vector density, hence we predict risk via vector prediction. METHODS AND FINDINGS We make use of surveillance data on Aedes aegypti larvae collected by the Taiwan Centers for Disease Control as part of the national routine entomological surveillance of dengue, and weather data simulated using the IBM's Containerized Forecasting Workflow, a high spatial- and temporal-resolution forecasting system. We propose a two stage risk prediction system for assessing dengue transmission via Aedes aegypti mosquitoes. In stage one, we perform a logistic regression to determine whether larvae are present or absent at the locations of interest using weather attributes as the explanatory variables. The results are then aggregated to an administrative division, with presence in the division determined by a threshold percentage of larvae positive locations resulting from a bootstrap approach. In stage two, larvae counts are estimated for the predicted larvae positive divisions from stage one, using a zero-inflated negative binomial model. This model identifies the larvae positive locations with 71% accuracy and predicts the larvae numbers producing a coverage probability of 98% over 95% nominal prediction intervals. This two-stage model improves the overall accuracy of identifying larvae positive locations by 29%, and the mean squared error of predicted larvae numbers by 9.6%, against a single-stage approach which uses a zero-inflated binomial regression approach. CONCLUSIONS We demonstrate a risk prediction system using high resolution weather data can provide valuable insight to the distribution of risk over a geographical region. The work also shows that a two-stage approach is beneficial in predicting risk in non-homogeneous regions, where the risk is localised.
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Affiliation(s)
- Chathurika Hettiarachchige
- IBM Research Australia, Southgate, Victoria, Australia
- School of Mathematics and Statistics, The University of Melbourne, Parkville, Victoria, Australia
| | | | - Timothy Lynar
- IBM Research Australia, Southgate, Victoria, Australia
| | - Roslyn I. Hickson
- IBM Research Australia, Southgate, Victoria, Australia
- School of Mathematics and Statistics, The University of Melbourne, Parkville, Victoria, Australia
| | - Manoj Gambhir
- IBM Research Australia, Southgate, Victoria, Australia
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Abstract
In this issue of the Biomedical Journal we explore the history of dengue infection in Taiwan and what current trends have to say about the vector responsible for transmitting the disease on the island. We focus on original research reporting the development of a new perfusion bioreactor to engineer bone from human cord blood stem cells. Finally, we look at trends in osteoporosis in Taiwan and how they highlight the success of public health campaigns.
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Affiliation(s)
- Emma Louise Walton
- Staff Writer at the Biomedical Journal, 56 Dronningens Gate, 7012 Trondheim, Norway.
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24
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Chen WJ. Dengue outbreaks and the geographic distribution of dengue vectors in Taiwan: A 20-year epidemiological analysis. Biomed J 2018; 41:283-289. [PMID: 30580791 PMCID: PMC6306330 DOI: 10.1016/j.bj.2018.06.002] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2018] [Revised: 06/01/2018] [Accepted: 06/14/2018] [Indexed: 11/17/2022] Open
Abstract
Dengue fever is an important mosquito-borne viral infectious disease that mostly occurs in tropical and subtropical areas of the world. According to epidemiological data from the Center for Disease Control of Taiwan, more than 98.62% of outbreaks of indigenous total dengue cases were reported in the southern part of Taiwan. Southern Taiwan is an aggregate area encompassing Tainan, Kaohsiung, and Pingtung, all of which are located below the Tropic of Cancer (23º35'N). With a few exceptions, dengue outbreaks mainly occur in southern Taiwan which is highly associated or overlaps with the prevalence of Aedes aegypti. A.aegypti is presumed to be absent from the northern part of Taiwan, while Aedes albopictus breeds in areas throughout the island. According a collection of 20 years of epidemiological data from Taiwan, the inability of A. aegypti to survive the winter weather in northern Taiwan may account for its restricted geographical distribution and that of dengue outbreaks it transmits. A.aegypti, unlike temperate strains of A. albopictus, lacks embryonic diapause signaled by a short photoperiod which thus reduces its cold-hardiness. Therefore it is intolerant of low temperatures that frequently accompany rains and unable to survive during winter in the northern part of Taiwan.
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Affiliation(s)
- Wei-June Chen
- Department of Public Health and Parasitology, College of Medicine, Chang Gung University, Taoyuan, Taiwan; Molecular Infectious Disease Research Center, Chang Gung Memorial Hospital at Linkou, Taoyuan, Taiwan.
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25
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Ng KC, Chaves LF, Tsai KH, Chuang TW. Increased Adult Aedes aegypti and Culex quinquefasciatus (Diptera: Culicidae) Abundance in a Dengue Transmission Hotspot, Compared to a Coldspot, within Kaohsiung City, Taiwan. INSECTS 2018; 9:insects9030098. [PMID: 30104501 PMCID: PMC6164640 DOI: 10.3390/insects9030098] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Revised: 07/30/2018] [Accepted: 08/10/2018] [Indexed: 12/30/2022]
Abstract
The assumption that vector abundance differences might drive spatial and temporal heterogeneities in vector-borne disease transmission is common, though data supporting it is scarce. Here, we present data from two common mosquito species Aedes aegypti (Linnaeus) and Culex quinquefasciatus Say, biweekly sampled as adults, from March 2016 through December 2017, with BG-sentinel traps in two neighboring districts of Kaohsiung City (KC), Taiwan. One district has historically been a dengue transmission hotspot (Sanmin), and the other a coldspot (Nanzih). We collected a total 41,027 mosquitoes, and we found that average mosquito abundance (mean ± S.D.) was higher in Sanmin (Ae. aegypti: 9.03 ± 1.46; Cx. quinquefasciatus: 142.57 ± 14.38) than Nanzih (Ae. aegypti: 6.21 ± 0.47; Cx. quinquefasciatus: 63.37 ± 8.71) during the study period. In both districts, Ae. aegypti and Cx. quinquefasciatus population dynamics were sensitive to changes in temperature, the most platykurtic environmental variable at KC during the study period, a pattern predicted by Schmalhausen’s law, which states that organisms are more sensitive to small changes in environmental variables whose average value is more uncertain than its extremes. Our results also suggest that differences in Ae. aegypti abundance might be responsible for spatial differences in dengue transmission at KC. Our comparative approach, where we also observed a significant increment in the abundance of Cx. quinquefasciatus in the dengue transmission hotspot, suggests this area might be more likely to experience outbreaks of other vector borne diseases and should become a primary focus for vector surveillance and control.
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Affiliation(s)
- Ka-Chon Ng
- College of Public Health, National Taiwan University, Taipei 10055, Taiwan.
| | - Luis Fernando Chaves
- Instituto Costarricense de Investigación y Enseñanza en Nutrición y Salud (INCIENSA), Apartado Postal 4-2250, Tres Ríos, Cartago, Costa Rica.
- Programa de Investigación en Enfermedades Tropicales (PIET), Escuela de Medicina Veterinaria, Universidad Nacional, Apartado Postal 304-3000, Heredia, Costa Rica.
| | - Kun-Hsien Tsai
- College of Public Health, National Taiwan University, Taipei 10055, Taiwan.
| | - Ting-Wu Chuang
- Department of Molecular Parasitology and Tropical Diseases, School of Medicine, College of Medicine, Taipei Medical University, No. 250, Wuxing Street, Xinyi District, Taipei 11031, Taiwan.
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26
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Lounibos LP, Juliano SA. Where Vectors Collide: The Importance of Mechanisms Shaping the Realized Niche for Modeling Ranges of Invasive Aedes Mosquitoes. Biol Invasions 2018; 20:1913-1929. [PMID: 30220875 PMCID: PMC6133263 DOI: 10.1007/s10530-018-1674-7] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2017] [Accepted: 01/19/2018] [Indexed: 10/18/2022]
Abstract
The vector mosquitoes Aedes aegypti (L.), native to Africa, and Aedes albopictus (Skuse), native to Asia, are widespread invasives whose spatial distributions frequently overlap. Predictive models of their distributions are typically correlative rather than mechanistic, and based on only abiotic variables describing putative environmental requirements despite extensive evidence of competitive interactions leading to displacements. Here we review putative roles of competition contributing to distribution changes where the two species meet. The strongest evidence for competitive displacements comes from multiple examples of habitat segregation where the two species co-occur and massive reductions in the range and abundance of A. aegypti attributable to A. albopictus invasions in the southeastern U.S.A. and Bermuda (U.K). We summarize evidence to support the primacy of asymmetric reproductive interference, or satyrization, and larval resource competition, both favoring A. albopictus, as displacement mechanisms. Where evidence of satyrization or interspecific resource competition is weak, differences in local environments or alternative ecologies or behaviors of these Aedes spp. may explain local variation in the outcomes of invasions. Predictive distribution modeling for both these major disease vectors needs to incorporate species interactions between them as an important process that is likely to limit their realized niches and future distributions. Experimental tests of satyrization and resource competition are needed across the broad ranges of these species, as are models that incorporate both reproductive interference and resource competition to evaluate interaction strengths and mechanisms. These vectors exemplify how fundamental principles of community ecology may influence distributions of invasive species.
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Affiliation(s)
- L Philip Lounibos
- Florida Medical Entomology Laboratory, University of Florida, 200 9 St SE, Vero Beach FL 32962
| | - Steven A Juliano
- School of Biological Sciences, Illinois State University, Normal, Illinois 61790-4120, USA
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Chen TH, Wu YJ, Hou JN, Chiang YH, Cheng CC, Sifiyatun E, Chiu CH, Wang LC, Chen WJ. A novel p53 paralogue mediates antioxidant defense of mosquito cells to survive dengue virus replication. Virology 2018; 519:156-169. [PMID: 29727815 DOI: 10.1016/j.virol.2018.04.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2018] [Revised: 03/31/2018] [Accepted: 04/16/2018] [Indexed: 01/22/2023]
Abstract
Mosquito cells allow dengue viruses (DENVs) to undergo replication without causing serious deleterious effects on the cells, leading to advantages for dissemination to other cells. Despite this, increased accumulation of reactive oxygen species (ROS) is usually detected in C6/36 cells with DENV2 infection as shown in mammalian cells. Uniquely, oxidative stress caused by the ROS is alleviated by eliciting antioxidant defense which leads to protection of mosquito cells from the infection. In the present study, a novel p53 paralogue (p53-2) was identified and proved to be regulated in C6/36 cells with DENV2 infection. With a gene-knockdown technique, p53-2 was demonstrated to transcribe catalase which plays a critical role in reducing ROS accumulation and the death rate of infected cells. Ecologically, a higher survival rate of mosquito cells is a prerequisite for prosperous production of viral progeny, allowing infected mosquitoes to remain healthy and active for virus transmission.
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Affiliation(s)
- Tien-Huang Chen
- Departments of Public Health and Parasitology, Chang Gung University, Kwei-San, Tao-Yuan 33332, Taiwan
| | - Yi-Jun Wu
- Graduate Institute of Biomedical Sciences, Chang Gung University, Kwei-San, Tao-Yuan 33332, Taiwan
| | - Jiun-Nan Hou
- Graduate Institute of Biomedical Sciences, Chang Gung University, Kwei-San, Tao-Yuan 33332, Taiwan
| | - Yi-Hsuan Chiang
- Departments of Public Health and Parasitology, Chang Gung University, Kwei-San, Tao-Yuan 33332, Taiwan
| | - Chih-Chieh Cheng
- Graduate Institute of Biomedical Sciences, Chang Gung University, Kwei-San, Tao-Yuan 33332, Taiwan
| | - Eny Sifiyatun
- Graduate Institute of Biomedical Sciences, Chang Gung University, Kwei-San, Tao-Yuan 33332, Taiwan; Program in Tropical Medical Science, Gadjah Mada University, Yogyakartan, Indonesia
| | - Cheng-Hsun Chiu
- Molecular Infectious Disease Research Center, Chang Gung Memorial Hospital, Kwei-San, Tao-Yuan, Taiwan; Division of Pediatric Infectious Diseases, Department of Pediatrics, Chang Gung Children's Hospital, Chang Gung University College of Medicine, Kwei-San, Tao-Yuan, Taiwan
| | - Lian-Chen Wang
- Departments of Public Health and Parasitology, Chang Gung University, Kwei-San, Tao-Yuan 33332, Taiwan; Graduate Institute of Biomedical Sciences, Chang Gung University, Kwei-San, Tao-Yuan 33332, Taiwan; Molecular Infectious Disease Research Center, Chang Gung Memorial Hospital, Kwei-San, Tao-Yuan, Taiwan.
| | - Wei-June Chen
- Departments of Public Health and Parasitology, Chang Gung University, Kwei-San, Tao-Yuan 33332, Taiwan; Graduate Institute of Biomedical Sciences, Chang Gung University, Kwei-San, Tao-Yuan 33332, Taiwan; Molecular Infectious Disease Research Center, Chang Gung Memorial Hospital, Kwei-San, Tao-Yuan, Taiwan.
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28
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Luh DL, Liu CC, Luo YR, Chen SC. Economic cost and burden of dengue during epidemics and non-epidemic years in Taiwan. J Infect Public Health 2018; 11:215-223. [DOI: 10.1016/j.jiph.2017.07.021] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Revised: 05/29/2017] [Accepted: 07/09/2017] [Indexed: 10/19/2022] Open
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Chin WCB, Wen TH, Sabel CE, Wang IH. A geo-computational algorithm for exploring the structure of diffusion progression in time and space. Sci Rep 2017; 7:12565. [PMID: 28974752 PMCID: PMC5626785 DOI: 10.1038/s41598-017-12852-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Accepted: 09/14/2017] [Indexed: 01/03/2023] Open
Abstract
A diffusion process can be considered as the movement of linked events through space and time. Therefore, space-time locations of events are key to identify any diffusion process. However, previous clustering analysis methods have focused only on space-time proximity characteristics, neglecting the temporal lag of the movement of events. We argue that the temporal lag between events is a key to understand the process of diffusion movement. Using the temporal lag could help to clarify the types of close relationships. This study aims to develop a data exploration algorithm, namely the TrAcking Progression In Time And Space (TaPiTaS) algorithm, for understanding diffusion processes. Based on the spatial distance and temporal interval between cases, TaPiTaS detects sub-clusters, a group of events that have high probability of having common sources, identifies progression links, the relationships between sub-clusters, and tracks progression chains, the connected components of sub-clusters. Dengue Fever cases data was used as an illustrative case study. The location and temporal range of sub-clusters are presented, along with the progression links. TaPiTaS algorithm contributes a more detailed and in-depth understanding of the development of progression chains, namely the geographic diffusion process.
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Affiliation(s)
| | - Tzai-Hung Wen
- Department of Geography, National Taiwan University, Taipei City, 10617, Taiwan.
| | - Clive E Sabel
- Department of Environmental Science, Aarhus University, 4000, Roskilde, Denmark
| | - I-Hsiang Wang
- Department of Geography, National Taiwan University, Taipei City, 10617, Taiwan
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XBP1-Mediated BiP/GRP78 Upregulation Copes with Oxidative Stress in Mosquito Cells during Dengue 2 Virus Infection. BIOMED RESEARCH INTERNATIONAL 2017; 2017:3519158. [PMID: 29098151 PMCID: PMC5642879 DOI: 10.1155/2017/3519158] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/03/2017] [Revised: 08/01/2017] [Accepted: 08/23/2017] [Indexed: 12/23/2022]
Abstract
Dengue viruses (DENVs) cause dengue fever which is an important mosquito-borne disease in tropical areas. Generally, DENV does not cause cellular damage in mosquito cells. However, alterations in cytosolic calcium ions ([Ca2+]cyt) and the mitochondrial membrane potential (MMP), as well as accumulated reactive oxygen species (ROS), including superoxide anions (O2∙-) and hydrogen peroxide (H2O2), can be detected in C6/36 cells with DENV2 infection. Evident upregulation of BiP/GRP78 also appeared at 24 h postinfection in DENV2-infected C6/36 cells. As expression of BiP/GRP78 mRNA was reduced when the transcription factor X-box-binding protein-1 (XBP1) was knocked down in C6/36 cells, it demonstrated that BiP/GRP78 is the target gene regulated by the XBP1 signal pathway. We further demonstrated that the expression and splicing activity of XBP1 were upregulated in parallel with DENV2 infection in C6/36 cells. In C6/36 cells with BiP/GRP78 overexpression, oxidative stress indicators including [Ca2+]cyt, MMP, O2∙-, and H2O2 were all pushed back to normal. Taken together, DENV2 activates XBP1 at earlier stage of infection, followed by upregulating BiP/GRP78 in mosquito cells. This regulatory pathway contributes a cascade in relation to oxidative stress alleviation. The finding provides insights into elucidating how mosquitoes can healthily serve as a vector of arboviruses in nature.
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Hou JN, Chen TH, Chiang YH, Peng JY, Yang TH, Cheng CC, Sofiyatun E, Chiu CH, Chiang-Ni C, Chen WJ. PERK Signal-Modulated Protein Translation Promotes the Survivability of Dengue 2 Virus-Infected Mosquito Cells and Extends Viral Replication. Viruses 2017; 9:v9090262. [PMID: 28930151 PMCID: PMC5618028 DOI: 10.3390/v9090262] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2017] [Revised: 09/15/2017] [Accepted: 09/17/2017] [Indexed: 01/03/2023] Open
Abstract
Survival of mosquitoes from dengue virus (DENV) infection is a prerequisite of viral transmission to the host. This study aimed to see how mosquito cells can survive the infection during prosperous replication of the virus. In C6/36 cells, global protein translation was shut down after infection by DENV type 2 (DENV2). However, it returned to a normal level when infected cells were treated with an inhibitor of the protein kinase RNA (PKR)-like ER kinase (PERK) signaling pathway. Based on a 7-Methylguanosine 5′-triphosphate (m7GTP) pull-down assay, the eukaryotic translation initiation factor 4F (eIF4F) complex was also identified in DENV2-infected cells. This suggests that most mosquito proteins are synthesized via canonical cap-dependent translation. When the PERK signal pathway was inhibited, both accumulation of reactive oxygen species and changes in the mitochondrial membrane potential increased. This suggested that ER stress response was alleviated through the PERK-mediated shutdown of global proteins in DENV2-infected C6/36 cells. In the meantime, the activities of caspases-9 and -3 and the apoptosis-related cell death rate increased in C6/36 cells with PERK inhibition. This reflected that the PERK-signaling pathway is involved in determining cell survival, presumably by reducing DENV2-induced ER stress. Looking at the PERK downstream target, α-subunit of eukaryotic initiation factor 2 (eIF2α), an increased phosphorylation status was only shown in infected C6/36 cells. This indicated that recruitment of ribosome binding to the mRNA 5′-cap structure could have been impaired in cap-dependent translation. It turned out that shutdown of cellular protein translation resulted in a pro-survival effect on mosquito cells in response to DENV2 infection. As synthesis of viral proteins was not affected by the PERK signal pathway, an alternate mode other than cap-dependent translation may be utilized. This finding provides insights into elucidating how the PERK signal pathway modulates dynamic translation of proteins and helps mosquito cells survive continuous replication of the DENV2. It was ecologically important for virus amplification in mosquitoes and transmission to humans.
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Affiliation(s)
- Jiun-Nan Hou
- Graduate Institute of Biomedical Sciences, Chang Gung University, Kwei-San, Tao-Yuan 33332, Taiwan.
| | - Tien-Huang Chen
- Department of Public Health and Parasitology, Chang Gung University, Kwei-San, Tao-Yuan 33332, Taiwan.
| | - Yi-Hsuan Chiang
- Department of Public Health and Parasitology, Chang Gung University, Kwei-San, Tao-Yuan 33332, Taiwan.
| | - Jing-Yun Peng
- Graduate Institute of Biomedical Sciences, Chang Gung University, Kwei-San, Tao-Yuan 33332, Taiwan.
| | - Tsong-Han Yang
- Department of Public Health and Parasitology, Chang Gung University, Kwei-San, Tao-Yuan 33332, Taiwan.
| | - Chih-Chieh Cheng
- Graduate Institute of Biomedical Sciences, Chang Gung University, Kwei-San, Tao-Yuan 33332, Taiwan.
| | - Eny Sofiyatun
- Graduate Institute of Biomedical Sciences, Chang Gung University, Kwei-San, Tao-Yuan 33332, Taiwan.
- Environmental Health Department, Banjarnegara Polytechnic, Central Java 53482, Indonesia.
| | - Cheng-Hsun Chiu
- Molecular Infectious Disease Research Center, Chang Gung Memorial Hospital, Kwei-San, Tao-Yuan 33332, Taiwan.
- Division of Pediatric Infectious Diseases, Department of Pediatrics, Chang Gung Children's Hospital, Chang Gung University College of Medicine, Kwei-San, Tao-Yuan 33305, Taiwan.
| | - Chuan Chiang-Ni
- Graduate Institute of Biomedical Sciences, Chang Gung University, Kwei-San, Tao-Yuan 33332, Taiwan.
- Department of Microbiology and Immunology, Chang Gung University, Kwei-San, Tao-Yuan 33332, Taiwan.
| | - Wei-June Chen
- Graduate Institute of Biomedical Sciences, Chang Gung University, Kwei-San, Tao-Yuan 33332, Taiwan.
- Department of Public Health and Parasitology, Chang Gung University, Kwei-San, Tao-Yuan 33332, Taiwan.
- Molecular Infectious Disease Research Center, Chang Gung Memorial Hospital, Kwei-San, Tao-Yuan 33332, Taiwan.
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Azar SR, Roundy CM, Rossi SL, Huang JH, Leal G, Yun R, Fernandez-Salas I, Vitek CJ, Paploski IAD, Stark PM, Vela J, Debboun M, Reyna M, Kitron U, Ribeiro GS, Hanley KA, Vasilakis N, Weaver SC. Differential Vector Competency of Aedes albopictus Populations from the Americas for Zika Virus. Am J Trop Med Hyg 2017; 97:330-339. [PMID: 28829735 PMCID: PMC5544086 DOI: 10.4269/ajtmh.16-0969] [Citation(s) in RCA: 62] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2016] [Accepted: 02/22/2017] [Indexed: 01/15/2023] Open
Abstract
To evaluate the potential role of Aedes albopictus (Skuse) as a vector of Zika virus (ZIKV), colonized mosquitoes of low generation number (≤ F5) from Brazil, Houston, and the Rio Grande Valley of Texas engorged on viremic mice infected with ZIKV strains originating from Senegal, Cambodia, Mexico, Brazil, or Puerto Rico. Vector competence was established by monitoring infection, dissemination, and transmission potential after 3, 7, and 14 days of extrinsic incubation. Positive saliva samples were assayed for infectious titer. Although all three mosquito populations were susceptible to all ZIKV strains, rates of infection, dissemination, and transmission differed among mosquito and virus strains. Aedes albopictus from Salvador, Brazil, were the least efficient vectors, demonstrating susceptibility to infection to two American strains of ZIKV but failing to shed virus in saliva. Mosquitoes from the Rio Grande Valley were the most efficient vectors and were capable of shedding all three tested ZIKV strains into saliva after 14 days of extrinsic incubation. In particular, ZIKV strain DakAR 41525 (Senegal 1954) was significantly more efficient at dissemination and saliva deposition than the others tested in Rio Grande mosquitoes. Overall, our data indicate that, while Ae. albopictus is capable of transmitting ZIKV, its competence is potentially dependent on geographic origin of both the mosquito population and the viral strain.
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Affiliation(s)
- Sasha R. Azar
- Department of Pathology, Institute for Human Infections and Immunity, University of Texas Medical Branch, Galveston, Texas
- Center for Tropical Diseases, University of Texas Medical Branch, Galveston, Texas
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, Texas
| | - Christopher M. Roundy
- Department of Pathology, Institute for Human Infections and Immunity, University of Texas Medical Branch, Galveston, Texas
- Center for Tropical Diseases, University of Texas Medical Branch, Galveston, Texas
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, Texas
| | - Shannan L. Rossi
- Department of Pathology, Institute for Human Infections and Immunity, University of Texas Medical Branch, Galveston, Texas
- Center for Tropical Diseases, University of Texas Medical Branch, Galveston, Texas
| | - Jing H. Huang
- Department of Pathology, Institute for Human Infections and Immunity, University of Texas Medical Branch, Galveston, Texas
- Center for Tropical Diseases, University of Texas Medical Branch, Galveston, Texas
| | - Grace Leal
- Department of Pathology, Institute for Human Infections and Immunity, University of Texas Medical Branch, Galveston, Texas
- Center for Tropical Diseases, University of Texas Medical Branch, Galveston, Texas
| | - Ruimei Yun
- Department of Pathology, Institute for Human Infections and Immunity, University of Texas Medical Branch, Galveston, Texas
- Center for Tropical Diseases, University of Texas Medical Branch, Galveston, Texas
| | | | | | - Igor A. D. Paploski
- Centro de Pesquisas Gonçalo Moniz, Fundação Oswaldo Cruz, Ministério da Saúde, Candeal, Salvador, Brazil
- Instituto de Saúde Coletiva, Universidade Federal da Bahia, Salvador, Brazil
| | - Pamela M. Stark
- Mosquito and Vector Control Division, Harris County Public Health, Houston, Texas
| | - Jeremy Vela
- Mosquito and Vector Control Division, Harris County Public Health, Houston, Texas
| | - Mustapha Debboun
- Mosquito and Vector Control Division, Harris County Public Health, Houston, Texas
| | - Martin Reyna
- Mosquito and Vector Control Division, Harris County Public Health, Houston, Texas
| | - Uriel Kitron
- Population Biology, Ecology, and Evolution Graduate Program, Graduate Division of Biological and Biomedical Sciences, Department of Environmental Sciences, Emory University, Atlanta, Georgia
| | - Guilherme S. Ribeiro
- Centro de Pesquisas Gonçalo Moniz, Fundação Oswaldo Cruz, Ministério da Saúde, Candeal, Salvador, Brazil
- Instituto de Saúde Coletiva, Universidade Federal da Bahia, Salvador, Brazil
| | - Kathryn A. Hanley
- Department of Biology, New Mexico State University, Las Cruces, New Mexico
| | - Nikos Vasilakis
- Department of Pathology, Institute for Human Infections and Immunity, University of Texas Medical Branch, Galveston, Texas
- Center for Tropical Diseases, University of Texas Medical Branch, Galveston, Texas
| | - Scott C. Weaver
- Department of Pathology, Institute for Human Infections and Immunity, University of Texas Medical Branch, Galveston, Texas
- Center for Tropical Diseases, University of Texas Medical Branch, Galveston, Texas
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, Texas
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Yang S, Kou SC, Lu F, Brownstein JS, Brooke N, Santillana M. Advances in using Internet searches to track dengue. PLoS Comput Biol 2017; 13:e1005607. [PMID: 28727821 PMCID: PMC5519005 DOI: 10.1371/journal.pcbi.1005607] [Citation(s) in RCA: 63] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2016] [Accepted: 06/02/2017] [Indexed: 11/23/2022] Open
Abstract
Dengue is a mosquito-borne disease that threatens over half of the world’s population. Despite being endemic to more than 100 countries, government-led efforts and tools for timely identification and tracking of new infections are still lacking in many affected areas. Multiple methodologies that leverage the use of Internet-based data sources have been proposed as a way to complement dengue surveillance efforts. Among these, dengue-related Google search trends have been shown to correlate with dengue activity. We extend a methodological framework, initially proposed and validated for flu surveillance, to produce near real-time estimates of dengue cases in five countries/states: Mexico, Brazil, Thailand, Singapore and Taiwan. Our result shows that our modeling framework can be used to improve the tracking of dengue activity in multiple locations around the world. As communicable diseases spread in our societies, people frequently turn to the Internet to search for medical information. In recent years, multiple research teams have investigated how to utilize Internet users’ search activity to track infectious diseases around our planet. In this article, we show that a methodology, originally developed to track flu in the US, can be extended to improve dengue surveillance in multiple countries/states where dengue has been observed in the last several years. Our result suggests that our methodology performs best in dengue-endemic areas with high number of yearly cases and with sustained seasonal incidence.
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Affiliation(s)
- Shihao Yang
- Department of Statistics, Harvard University, Cambridge, MA, USA
| | - Samuel C. Kou
- Department of Statistics, Harvard University, Cambridge, MA, USA
- * E-mail: (MS); (SCK)
| | - Fred Lu
- Computational Health Informatics Program, Boston Children’s Hospital, Boston, MA, USA
| | - John S. Brownstein
- Computational Health Informatics Program, Boston Children’s Hospital, Boston, MA, USA
- Harvard Medical School, Boston, MA, USA
| | | | - Mauricio Santillana
- Computational Health Informatics Program, Boston Children’s Hospital, Boston, MA, USA
- Harvard Medical School, Boston, MA, USA
- * E-mail: (MS); (SCK)
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Joanne S, Vythilingam I, Teoh BT, Leong CS, Tan KK, Wong ML, Yugavathy N, AbuBakar S. Vector competence of Malaysian Aedes albopictus with and without Wolbachia to four dengue virus serotypes. Trop Med Int Health 2017; 22:1154-1165. [PMID: 28653334 DOI: 10.1111/tmi.12918] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
OBJECTIVE To determine the susceptibility status of Aedes albopictus with and without Wolbachia to the four dengue virus serotypes. METHODS Two newly colonised colonies of Ae. albopictus from the wild were used for the study. One colony was naturally infected with Wolbachia while in the other Wolbachia was removed by tetracycline treatment. Both colonies were orally infected with dengue virus-infected fresh blood meal. Dengue virus load was measured using quantitative RT-PCR at four-time intervals in the salivary glands, midguts and ovaries. RESULTS Wolbachia did not significantly affect Malaysian Ae. albopictus dengue infection or the dissemination rate for all four dengue virus serotypes. Malaysian Ae. albopictus had the highest replication kinetics for DENV-1 and the highest salivary gland and midgut infection rate for DENV-4. CONCLUSION Wolbachia, which naturally exists in Malaysian Ae. albopictus, does not significantly affect dengue virus replication. Malaysian Ae. albopictus is susceptible to dengue virus infections and capable of transmitting dengue virus, especially DENV-1 and DENV-4. Removal of Wolbachia from Malaysian Ae. albopictus would not reduce their susceptibility status.
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Affiliation(s)
- Sylvia Joanne
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Indra Vythilingam
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Boon-Teong Teoh
- Department of Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Cherng-Shii Leong
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Kim-Kee Tan
- Department of Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Meng-Li Wong
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Nava Yugavathy
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Sazaly AbuBakar
- Department of Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
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Wei K, Li Y. Global evolutionary history and spatio-temporal dynamics of dengue virus type 2. Sci Rep 2017; 7:45505. [PMID: 28378782 PMCID: PMC5381229 DOI: 10.1038/srep45505] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2016] [Accepted: 02/27/2017] [Indexed: 11/08/2022] Open
Abstract
DENV-2 spread throughout the tropical and subtropical regions globally, which is implicated in deadly outbreaks of DHF and DSS. Since dengue cases have grown dramatically in recent years, about half of the world's population is now at risk. Our timescale analysis indicated that the most recent common ancestor existed about 100 years ago. The rate of nucleotide substitution was estimated to be 8.94 × 10-4 subs/site/year. Selection pressure analysis showed that two sites 160 and 403 were under positive selection, while E gene is mainly shaped by stronger purifying selection. BSP analysis showed that estimating effective population size from samples of sequences has undergone three obvious increases, additionally, Caribbean and Puerto Rico maintained higher levels of genetic diversity relative to other 6 representative geographical populations using GMRF method. The phylogeographic analysis indicated that two major transmission routes are from South America to Caribbean and East&SouthAsia to Puerto Rico. The trunk reconstruction confirmed that the viral evolution spanned 50 years occurred primarily in Southeast Asia and East&South Asia. In addition, phylogeographic association-trait analysis indicated that the viral phenotypes are highly correlated with phylogeny in Nicaragua and Puerto Rico (P < 0.05).
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Affiliation(s)
- Kaifa Wei
- School of Biological Sciences and Biotechnology, Minnan Normal University, Zhangzhou 363000, China
| | - Yuhan Li
- School of Biological Sciences and Biotechnology, Minnan Normal University, Zhangzhou 363000, China
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Consecutive large dengue outbreaks in Taiwan in 2014-2015. Emerg Microbes Infect 2016; 5:e123. [PMID: 27924810 PMCID: PMC5180368 DOI: 10.1038/emi.2016.124] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2016] [Revised: 09/21/2016] [Accepted: 09/23/2016] [Indexed: 11/08/2022]
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Tsai PJ, Teng HJ. Role of Aedes aegypti (Linnaeus) and Aedes albopictus (Skuse) in local dengue epidemics in Taiwan. BMC Infect Dis 2016; 16:662. [PMID: 27829399 PMCID: PMC5103501 DOI: 10.1186/s12879-016-2002-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2016] [Accepted: 10/28/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Aedes mosquitoes in Taiwan mainly comprise Aedes albopictus and Ae. aegypti. However, the species contributing to autochthonous dengue spread and the extent at which it occurs remain unclear. Thus, in this study, we spatially analyzed real data to determine spatial features related to local dengue incidence and mosquito density, particularly that of Ae. albopictus and Ae. aegypti. METHODS We used bivariate Moran's I statistic and geographically weighted regression (GWR) spatial methods to analyze the globally spatial dependence and locally regressed relationship between (1) imported dengue incidences and Breteau indices (BIs) of Ae. albopictus, (2) imported dengue incidences and BI of Ae. aegypti, (3) autochthonous dengue incidences and BI of Ae. albopictus, (4) autochthonous dengue incidences and BI of Ae. aegypti, (5) all dengue incidences and BI of Ae. albopictus, (6) all dengue incidences and BI of Ae. aegypti, (7) BI of Ae. albopictus and human population density, and (8) BI of Ae. aegypti and human population density in 348 townships in Taiwan. RESULTS In the GWR models, regression coefficients of spatially regressed relationships between the incidence of autochthonous dengue and vector density of Ae. aegypti were significant and positive in most townships in Taiwan. However, Ae. albopictus had significant but negative regression coefficients in clusters of dengue epidemics. In the global bivariate Moran's index, spatial dependence between the incidence of autochthonous dengue and vector density of Ae. aegypti was significant and exhibited positive correlation in Taiwan (bivariate Moran's index = 0.51). However, Ae. albopictus exhibited positively significant but low correlation (bivariate Moran's index = 0.06). Similar results were observed in the two spatial methods between all dengue incidences and Aedes mosquitoes (Ae. aegypti and Ae. albopictus). The regression coefficients of spatially regressed relationships between imported dengue cases and Aedes mosquitoes (Ae. aegypti and Ae. albopictus) were significant in 348 townships in Taiwan. The results indicated that local Aedes mosquitoes do not contribute to the dengue incidence of imported cases. The density of Ae. aegypti positively correlated with the density of human population. By contrast, the density of Ae. albopictus negatively correlated with the density of human population in the areas of southern Taiwan. The results indicated that Ae. aegypti has more opportunities for human-mosquito contact in dengue endemic areas in southern Taiwan. CONCLUSIONS Ae. aegypti, but not Ae. albopictus, and human population density in southern Taiwan are closely associated with an increased risk of autochthonous dengue incidence.
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Affiliation(s)
- Pui-Jen Tsai
- Center for General Education, Aletheia University, New Taipei City, 25103, Taiwan, ROC.
| | - Hwa-Jen Teng
- Center for Diagnostics and Vaccine Development, Centers for Disease Control, Taipei, Taiwan, ROC
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Lounibos LP, Bargielowski I, Carrasquilla MC, Nishimura N. Coexistence of Aedes aegypti and Aedes albopictus (Diptera: Culicidae) in Peninsular Florida Two Decades After Competitive Displacements. JOURNAL OF MEDICAL ENTOMOLOGY 2016; 53:1385-1390. [PMID: 27493253 DOI: 10.1093/jme/tjw122] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2016] [Accepted: 07/13/2016] [Indexed: 05/26/2023]
Abstract
The spread of Aedes albopictus (Skuse) eastward in the mid-1980s from its initial establishment in Houston, TX, was associated with rapid declines and local disappearances of Aedes aegypti (L.) in Gulf Coast states and Florida where annual larval surveillance during the early 1990s described temporal and spatial patterns of competitive displacements in cemeteries and tire shops. Approximately 20 yr later in 2013-2014, we re-visited former collection sites and sampled aquatic immatures of these two species from tire shops in 10 cities on State Route 441 and from 9 cemeteries from Lakeland to Miami in southwest Florida. In the recent samples Ae. aegypti was recovered from three central Florida cities where it had not been detected in 1994, but its northern limit on Rte. 441, Apopka, did not change. Other evidence, such as trends at a few cemeteries, suggested a moderate resurgence of this species since 1994. Cage experiments that exposed female progeny of Ae. aegypti from recent Florida collection sites to interspecific mating by Ae. albopictus males showed that females from coexistence sites had evolved resistance to cross-mating, but Ae. aegypti from sites with no Ae. albopictus were relatively susceptible to satyrization. Habitat classifications of collection sites were reduced by principal component (PC) analysis to four variables that accounted for > 99% of variances; PCs with strong positive loadings for tree cover and ground vegetation were associated with collection sites yielding only Ae. albopictus Within the coexistence range of the two species, the numbers of Ae. aegypti among total Aedes collected were strongly correlated in stepwise logistic regression models with two habitat-derived PCs, distance from the coast, and annual rainfall and mean maximum temperatures at the nearest weather station. Subtle increases in the range of Ae. aegypti since its previous displacements are interpreted in the context of the evolution of resistance to mating interference, realized versus fundamental niches of the two species, and persisting competition with Ae. albopictus.
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Affiliation(s)
- L Philip Lounibos
- Florida Medical Entomology Laboratory, University of Florida, 200 9th St SE Vero Beach, FL 32962 (; ; ; ) and
| | - Irka Bargielowski
- Florida Medical Entomology Laboratory, University of Florida, 200 9th St SE Vero Beach, FL 32962 (; ; ; ) and
| | - María Cristina Carrasquilla
- Florida Medical Entomology Laboratory, University of Florida, 200 9th St SE Vero Beach, FL 32962 (; ; ; ) and
| | - Naoya Nishimura
- Florida Medical Entomology Laboratory, University of Florida, 200 9th St SE Vero Beach, FL 32962 (; ; ; ) and
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Viennet E, Ritchie SA, Williams CR, Faddy HM, Harley D. Public Health Responses to and Challenges for the Control of Dengue Transmission in High-Income Countries: Four Case Studies. PLoS Negl Trop Dis 2016; 10:e0004943. [PMID: 27643596 PMCID: PMC5028037 DOI: 10.1371/journal.pntd.0004943] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Dengue has a negative impact in low- and lower middle-income countries, but also affects upper middle- and high-income countries. Despite the efforts at controlling this disease, it is unclear why dengue remains an issue in affluent countries. A better understanding of dengue epidemiology and its burden, and those of chikungunya virus and Zika virus which share vectors with dengue, is required to prevent the emergence of these diseases in high-income countries in the future. The purpose of this review was to assess the relative burden of dengue in four high-income countries and to appraise the similarities and differences in dengue transmission. We searched PubMed, ISI Web of Science, and Google Scholar using specific keywords for articles published up to 05 May 2016. We found that outbreaks rarely occur where only Aedes albopictus is present. The main similarities between countries uncovered by our review are the proximity to dengue-endemic countries, the presence of a competent mosquito vector, a largely nonimmune population, and a lack of citizens’ engagement in control of mosquito breeding. We identified important epidemiological and environmental issues including the increase of local transmission despite control efforts, population growth, difficulty locating larval sites, and increased human mobility from neighboring endemic countries. Budget cuts in health and lack of practical vaccines contribute to an increased risk. To be successful, dengue-control programs for high-income countries must consider the epidemiology of dengue in other countries and use this information to minimize virus importation, improve the control of the cryptic larval habitat, and engage the community in reducing vector breeding. Finally, the presence of a communicable disease center is critical for managing and reducing future disease risks.
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Affiliation(s)
- Elvina Viennet
- Research School of Population Health, The Australian National University, Canberra, Australian Capital Territory, Australia
- Research and Development, Australian Red Cross Blood Service, Kelvin Grove, Queensland, Australia
- * E-mail:
| | - Scott A. Ritchie
- School of Public Health, Tropical Medicine and Rehabilitation Sciences, James Cook University, Cairns, Queensland, Australia
| | - Craig R. Williams
- Sansom Institute for Health Research, University of South Australia, Adelaide, SA, Australia
| | - Helen M. Faddy
- Research and Development, Australian Red Cross Blood Service, Kelvin Grove, Queensland, Australia
| | - David Harley
- Research School of Population Health, The Australian National University, Canberra, Australian Capital Territory, Australia
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Munusamy RG, Appadurai DR, Kuppusamy S, Michael GP, Savarimuthu I. Ovicidal and larvicidal activities of some plant extracts against Aedes aegypti L. and Culex quinquefasciatus Say (Diptera: Culicidae). ASIAN PACIFIC JOURNAL OF TROPICAL DISEASE 2016. [DOI: 10.1016/s2222-1808(16)61070-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Yang CF, Tu CH, Lo YP, Cheng CC, Chen WJ. Involvement of Tetraspanin C189 in Cell-to-Cell Spreading of the Dengue Virus in C6/36 Cells. PLoS Negl Trop Dis 2015; 9:e0003885. [PMID: 26132143 PMCID: PMC4488468 DOI: 10.1371/journal.pntd.0003885] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2015] [Accepted: 06/09/2015] [Indexed: 01/23/2023] Open
Abstract
Dengue virus (DENV) is naturally transmitted by mosquitoes to humans, infecting cells of both hosts. Unlike in mammalian cells, DENV usually does not cause extremely deleterious effects on cells of mosquitoes. Despite this, clustered progeny virions were found to form infection foci in a high density cell culture. It is thus interesting to know how the virus spreads among cells in tissues such as the midgut within live mosquitoes. This report demonstrates that cell-to-cell spread is one way for DENV to infect neighboring cells without depending on the "release and entry" mode. In the meantime, a membrane-bound vacuole incorporating tetraspanin C189 was formed in response to DENV infection in the C6/36 cell and was subsequently transported along with the contained virus from one cell to another. Knockdown of C189 in DENV-infected C6/36 cells is shown herein to reduce cell-to-cell transmission of the virus, which may be recovered by co-transfection with a C189-expressing vector in DENV-infected C6/36 cells. Moreover, cell-to-cell transmission usually occurred at the site where the donor cell directly contacts the recipient cell. It suggested that C189 is crucially involved in the intercellular spread of progeny viral particles between mosquito cells. This novel finding presumably accounts for the rapid and efficient infection of DENV after its initial replication within tissues of the mosquito.
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Affiliation(s)
- Chao-Fu Yang
- Graduate Institute of Biomedical Science, College of Medicine, Chang Gung University, Kwei-San, Tao-Yuan, Taiwan
| | - Cheng-Hsun Tu
- Graduate Institute of Biomedical Science, College of Medicine, Chang Gung University, Kwei-San, Tao-Yuan, Taiwan
| | - Yin-Ping Lo
- Graduate Institute of Biomedical Science, College of Medicine, Chang Gung University, Kwei-San, Tao-Yuan, Taiwan
| | - Chih-Chieh Cheng
- Graduate Institute of Biomedical Science, College of Medicine, Chang Gung University, Kwei-San, Tao-Yuan, Taiwan
| | - Wei-June Chen
- Graduate Institute of Biomedical Science, College of Medicine, Chang Gung University, Kwei-San, Tao-Yuan, Taiwan
- Department of Public Health and Parasitology, College of Medicine, Chang Gung University, Kwei-San, Tao-Yuan, Taiwan
- * E-mail:
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Kraemer MUG, Sinka ME, Duda KA, Mylne AQN, Shearer FM, Barker CM, Moore CG, Carvalho RG, Coelho GE, Van Bortel W, Hendrickx G, Schaffner F, Elyazar IRF, Teng HJ, Brady OJ, Messina JP, Pigott DM, Scott TW, Smith DL, Wint GRW, Golding N, Hay SI. The global distribution of the arbovirus vectors Aedes aegypti and Ae. albopictus. eLife 2015; 4:e08347. [PMID: 26126267 PMCID: PMC4493616 DOI: 10.7554/elife.08347] [Citation(s) in RCA: 1137] [Impact Index Per Article: 126.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2015] [Accepted: 06/18/2015] [Indexed: 02/06/2023] Open
Abstract
Dengue and chikungunya are increasing global public health concerns due to their rapid geographical spread and increasing disease burden. Knowledge of the contemporary distribution of their shared vectors, Aedes aegypti and Aedes albopictus remains incomplete and is complicated by an ongoing range expansion fuelled by increased global trade and travel. Mapping the global distribution of these vectors and the geographical determinants of their ranges is essential for public health planning. Here we compile the largest contemporary database for both species and pair it with relevant environmental variables predicting their global distribution. We show Aedes distributions to be the widest ever recorded; now extensive in all continents, including North America and Europe. These maps will help define the spatial limits of current autochthonous transmission of dengue and chikungunya viruses. It is only with this kind of rigorous entomological baseline that we can hope to project future health impacts of these viruses.
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Affiliation(s)
- Moritz UG Kraemer
- Spatial Ecology and Epidemiology Group, Department of Zoology, University of Oxford, Oxford, United Kingdom
| | - Marianne E Sinka
- Spatial Ecology and Epidemiology Group, Department of Zoology, University of Oxford, Oxford, United Kingdom
| | - Kirsten A Duda
- Spatial Ecology and Epidemiology Group, Department of Zoology, University of Oxford, Oxford, United Kingdom
| | - Adrian QN Mylne
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Freya M Shearer
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Christopher M Barker
- Department of Pathology, Microbiology, and Immunology, School of Veterinary Medicine, University of California, Davis, Davis, United States
| | - Chester G Moore
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, United States
| | | | | | - Wim Van Bortel
- European Centre for Disease Prevention and Control, Stockholm, Sweden
| | | | | | | | - Hwa-Jen Teng
- Center for Research, Diagnostics and Vaccine Development, Centers for Disease Control, Taipei, Taiwan
| | - Oliver J Brady
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Jane P Messina
- Spatial Ecology and Epidemiology Group, Department of Zoology, University of Oxford, Oxford, United Kingdom
| | - David M Pigott
- Spatial Ecology and Epidemiology Group, Department of Zoology, University of Oxford, Oxford, United Kingdom
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Thomas W Scott
- Fogarty International Center, National Institutes of Health, Bethesda, United States
- Department of Entomology and Nematology, University of California, Davis, Davis, United States
| | - David L Smith
- Spatial Ecology and Epidemiology Group, Department of Zoology, University of Oxford, Oxford, United Kingdom
- Fogarty International Center, National Institutes of Health, Bethesda, United States
- Sanaria Institute for Global Health and Tropical Medicine, Rockville, United States
| | - GR William Wint
- Environmental Research Group Oxford, Department of Zoology, University of Oxford, Oxford, United Kingdom
| | - Nick Golding
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Simon I Hay
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
- Fogarty International Center, National Institutes of Health, Bethesda, United States
- Institute for Health Metrics and Evaluation, University of Washington, Seattle, United States
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