1
|
Wang Y, Chitnis N, Fairbanks EL. Optimizing malaria vector control in the Greater Mekong Subregion: a systematic review and mathematical modelling study to identify desirable intervention characteristics. Parasit Vectors 2024; 17:162. [PMID: 38553759 PMCID: PMC10981350 DOI: 10.1186/s13071-024-06234-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Accepted: 03/04/2024] [Indexed: 04/01/2024] Open
Abstract
BACKGROUND In the Greater Mekong Subregion (GMS), new vector-control tools are needed to target mosquitoes that bite outside during the daytime and night-time to advance malaria elimination. METHODS We conducted systematic literature searches to generate a bionomic dataset of the main malaria vectors in the GMS, including human blood index (HBI), parity proportion, sac proportion (proportion with uncontracted ovary sacs, indicating the amount of time until they returned to host seeking after oviposition) and the resting period duration. We then performed global sensitivity analyses to assess the influence of bionomics and intervention characteristics on vectorial capacity. RESULTS Our review showed that Anopheles minimus, An. sinensis, An. maculatus and An. sundaicus display opportunistic blood-feeding behaviour, while An. dirus is more anthropophilic. Multivariate regression analysis indicated that environmental, climatic and sampling factors influence the proportion of parous mosquitoes, and resting duration varies seasonally. Sensitivity analysis highlighted HBI and parity proportion as the most influential bionomic parameters, followed by resting duration. Killing before feeding is always a desirable characteristic across all settings in the GMS. Disarming is also a desirable characteristic in settings with a low HBI. Repelling is only an effective strategy in settings with a low HBI and low parity proportion. Killing after feeding is only a desirable characteristic if the HBI and parity proportions in the setting are high. CONCLUSIONS Although in general adopting tools that kill before feeding would have the largest community-level effect on reducing outdoor transmission, other modes of action can be effective. Current tools in development which target outdoor biting mosquitoes should be implemented in different settings dependent on their characteristics.
Collapse
Affiliation(s)
- Yuqian Wang
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Kreuzstrasse 2, Allschwill, 4123, Basel, Switzerland
- University of Basel, Petersplatz 1, 4001, Basel, Switzerland
| | - Nakul Chitnis
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Kreuzstrasse 2, Allschwill, 4123, Basel, Switzerland
- University of Basel, Petersplatz 1, 4001, Basel, Switzerland
| | - Emma L Fairbanks
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Kreuzstrasse 2, Allschwill, 4123, Basel, Switzerland.
- University of Basel, Petersplatz 1, 4001, Basel, Switzerland.
| |
Collapse
|
2
|
Manu YA, Abduljalal A, Rabiu MB, Lawal RD, Saleh J, Safiyanu M. Identification of putative promoter elements for epsilon glutathione s-transferases genes associated with resistance to DDT in the malaria vector mosquito anopheles arabiensis. Sci Afr 2024; 23:None. [PMID: 38445294 PMCID: PMC10911095 DOI: 10.1016/j.sciaf.2023.e02047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2023] [Revised: 11/27/2023] [Accepted: 12/20/2023] [Indexed: 03/07/2024] Open
Abstract
The purpose of this study was to identify the putative regulatory elements in the promoter region of An. arabiensis strains which differed in susceptibility to DDT and compare with those identified in its sibling An. gambaie. Basal expression level of Epsilon class GSTs (Glutathione S - transferases) GSTe1 gene was 0.512 - 0.658 (95% CI) and GSTe2 0.672 - 1.204 (95% CI) in adults of DDT resistant KGB compared to 0.031 - 0.04 (95% CI) and 0.148 - 0.199 (95% CI) respectively in susceptible MAT strains of An. arabiensis. Induced mean expression of GSTe2 in larvae exposed to DDT for one hour was 0.901 - 1.172 (95% CI) in KGB and 0.475 - 0.724 (95% CI) in MAT strain. In present work, strain specific primers were used to amplify and sequenced the promoter regions of GSTe1 and GSTe2 in the KGB, MAT and field specimens. Computational analysis revealed presence of classical arthropod initiator sequence TCAGT and putative core promoter elements, GC, CAAT, TATA boxes. A typical TATA box was identified at 35 bp upstream Transcription Start Site (TSS) in GSTe1 but was absent in GSTe2. Several binding sites for regulatory elements downstream and multiple polymorphic sites were identified between strains. The role of these regulatory elements in transcription of these genes has not been determined. However, on comparison the 2 bp adenosine indel (insertion/deletion) which was essential in driving the promoter activity in An. gambiae was identified only DDT resistant KGB strain.
Collapse
Affiliation(s)
| | - Ado Abduljalal
- Centre for Infectious Disease Research, Bayero University, Kano
| | | | | | | | - Mahmud Safiyanu
- Department of Biochemistry, Yusuf Maitama Sule Univeristy, Kano
| |
Collapse
|
3
|
Haldar K, Alam MS, Koepfli C, Lobo NF, Phru CS, Islam MN, Faiz A, Khan WA, Haque R. Bangladesh in the era of malaria elimination. Trends Parasitol 2023; 39:760-773. [PMID: 37500334 DOI: 10.1016/j.pt.2023.06.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2023] [Revised: 06/06/2023] [Accepted: 06/20/2023] [Indexed: 07/29/2023]
Abstract
Bangladesh has dramatically reduced malaria by 93% from 2008 to 2020. The strategy has been district-wise, phased elimination; however, the last districts targeted for elimination include remote, forested regions which present several challenges for prevention, detection, and treatment of malaria. These districts border Myanmar which harbors Plasmodium falciparum malaria parasites resistant to artemisinins, key drugs used in artemisinin-based combination therapies (ACTs) that have been vital for control programs. Challenges in monitoring emergence of artemisinin resistance (AR), tracking parasite reservoirs, changes in vector behavior and responses to insecticides, as well as other environmental and host factors (including the migration of Forcibly Displaced Myanmar Nationals; FDMNs) may pose added hazards in the final phase of eliminating malaria in Bangladesh.
Collapse
Affiliation(s)
- Kasturi Haldar
- Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, IN, USA; Boler-Parseghian Center for Rare and Neglected Diseases, University of Notre Dame, Notre Dame, Indiana, IN, USA; Eck Institute of Global Health, University of Notre Dame, Notre Dame, Indiana, IN, USA.
| | - Mohammed Shafiul Alam
- Infectious Disease Division, International Center of Diarrheal Diseases, Bangladesh, (icddr, b), Dhaka, Bangladesh
| | - Cristian Koepfli
- Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, IN, USA; Eck Institute of Global Health, University of Notre Dame, Notre Dame, Indiana, IN, USA
| | - Neil F Lobo
- Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, IN, USA; Eck Institute of Global Health, University of Notre Dame, Notre Dame, Indiana, IN, USA
| | - Ching Shwe Phru
- Infectious Disease Division, International Center of Diarrheal Diseases, Bangladesh, (icddr, b), Dhaka, Bangladesh
| | | | - Abul Faiz
- Dev Care Foundation, Dhaka, Bangladesh
| | - Wasif Ali Khan
- Infectious Disease Division, International Center of Diarrheal Diseases, Bangladesh, (icddr, b), Dhaka, Bangladesh
| | - Rashidul Haque
- Infectious Disease Division, International Center of Diarrheal Diseases, Bangladesh, (icddr, b), Dhaka, Bangladesh
| |
Collapse
|
4
|
Boonroumkaew P, Rodpai R, Saeung A, Aupalee K, Saingamsook J, Poolphol P, Sadaow L, Sanpool O, Janwan P, Thanchomnang T, Intapan PM, Maleewong W. Bacterial community structure of Anopheles hyrcanus group, Anopheles nivipes, Anopheles philippinensis, and Anopheles vagus from a malaria-endemic area in Thailand. PLoS One 2023; 18:e0289733. [PMID: 37590198 PMCID: PMC10434920 DOI: 10.1371/journal.pone.0289733] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Accepted: 07/25/2023] [Indexed: 08/19/2023] Open
Abstract
Bacterial content of mosquitoes has given rise to the development of innovative tools that influence and seek to control malaria transmission. This study identified the bacterial microbiota in field-collected female adults of the Anopheles hyrcanus group and three Anopheles species, Anopheles nivipes, Anopheles philippinensis, and Anopheles vagus, from an endemic area in the southeastern part of Ubon Ratchathani Province, northeastern Thailand, near the Lao PDR-Cambodia-Thailand border. A total of 17 DNA libraries were generated from pooled female Anopheles abdomen samples (10 abdomens/ sample). The mosquito microbiota was characterized through the analysis of DNA sequences from the V3-V4 regions of the 16S rRNA gene, and data were analyzed in QIIME2. A total of 3,442 bacterial ASVs were obtained, revealing differences in the microbiota both within the same species/group and between different species/group. Statistical difference in alpha diversity was observed between An. hyrcanus group and An. vagus and between An. nivipes and An. vagus, and beta diversity analyses showed that the bacterial community of An. vagus was the most dissimilar from other species. The most abundant bacteria belonged to the Proteobacteria phylum (48%-75%) in which Pseudomonas, Serratia, and Pantoea were predominant genera among four Anopheles species/group. However, the most significantly abundant genus observed in each Anopheles species/group was as follows: Staphylococcus in the An. hyrcanus group, Pantoea in the An. nivipes, Rosenbergiella in An. philippinensis, and Pseudomonas in An. vagus. Particularly, Pseudomonas sp. was highly abundant in all Anopheles species except An. nivipes. The present study provides the first study on the microbiota of four potential malaria vectors as a starting step towards understanding the role of the microbiota on mosquito biology and ultimately the development of potential tools for malaria control.
Collapse
Affiliation(s)
- Patcharaporn Boonroumkaew
- Department of Parasitology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
- Mekong Health Science Research Institute, Khon Kaen University, Khon Kaen, Thailand
| | - Rutchanee Rodpai
- Department of Parasitology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
- Mekong Health Science Research Institute, Khon Kaen University, Khon Kaen, Thailand
| | - Atiporn Saeung
- Center of Insect Vector Study, Department of Parasitology, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
| | - Kittipat Aupalee
- Center of Insect Vector Study, Department of Parasitology, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
| | - Jassada Saingamsook
- Center of Insect Vector Study, Department of Parasitology, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
| | - Petchaboon Poolphol
- The Office of Disease Prevention and Control Region 10th, Ubon Ratchathani, Thailand
| | - Lakkhana Sadaow
- Department of Parasitology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
- Mekong Health Science Research Institute, Khon Kaen University, Khon Kaen, Thailand
| | - Oranuch Sanpool
- Department of Parasitology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
- Mekong Health Science Research Institute, Khon Kaen University, Khon Kaen, Thailand
| | - Penchom Janwan
- Department of Medical Technology, School of Allied Health Sciences, Walailak University, Nakhon Si Thammarat, Thailand
| | - Tongjit Thanchomnang
- Faculty of Medicine, Mahasarakham University, Kham Riang, Maha Sarakham, Thailand
| | - Pewpan M. Intapan
- Department of Parasitology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
- Mekong Health Science Research Institute, Khon Kaen University, Khon Kaen, Thailand
| | - Wanchai Maleewong
- Department of Parasitology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
- Mekong Health Science Research Institute, Khon Kaen University, Khon Kaen, Thailand
| |
Collapse
|
5
|
He ZQ, Hu YB, Wang D, Liu YT, Yang CY, Qian D, Zhou RM, Lu DL, Li SH, Liu Y, Zhang HW. Insecticide resistance of Anopheles sinensis after elimination of malaria in Henan Province, China. Parasit Vectors 2023; 16:180. [PMID: 37268968 DOI: 10.1186/s13071-023-05796-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Accepted: 05/02/2023] [Indexed: 06/04/2023] Open
Abstract
BACKGROUND Historically, malaria due to Plasmodium vivax has been epidemic in Henan Province, China, with Anopheles sinensis as the main vector. The most effective measures to prevent malaria transmission are based on vector control through the use of insecticides. However, insecticides exert a strong selective pressure on mosquito populations for insecticide resistance. The aim of this study was to investigate the susceptibility profile and population genetic characteristics of An. sinensis to provide basic data and scientific guidance for the study of resistance mechanisms and the control of An. sinensis in Henan Province. METHODS Adult Anopheles mosquitoes were collected at sites near local farmers' sheepfolds, pigsties and/or cowsheds located in Pingqiao, Xiangfu, Xiangcheng and Tanghe counties/districts of Henan Province during July-September 2021 for insecticide susceptibility testing. Molecular identification of collected mosquitoes as belonging to genus Anopheles was by PCR, and the frequencies of mutations in the knockdown resistance gene (kdr) and acetylcholinesterase-1 gene (ace-1) were detected using gene amplification. The mitochondrial DNA cytochrome oxidase subunit I (COI) gene was amplified in deltamethrin-resistant and deltamethrin-sensitive mosquitoes to analyze the genetic evolutionary relationship. RESULTS A total of 1409 Anopheles mosquitoes were identified by molecular identification, of which 1334 (94.68%) were An. sinensis, 28 (1.99%) were An. yatsushiroensis, 43 (3.05%) were An. anthropophagus and four (0.28%) were An. belenrae. The 24-h mortality rates of An. sinensis in Pingqiao, Tanghe, Xiangcheng and Xiangfu counties/districts exposed to deltamethrin were 85.85%, 25.38%, 29.73% and 7.66%, respectively; to beta-cyfluthrin, 36.24%, 70.91%, 34.33% and 3.28%, respectively; to propoxur, 68.39%, 80.60%, 37.62% and 9.29%, respectively; and to malathion, 97.43%, 97.67%, 99.21% and 64.23%, respectively. One mutation, G119S, was detected in the ace-1 gene. The frequencies of the main genotypes were 84.21% of specimens collected in Xiangfu (G/S), 90.63% of speciments collected in Xiangcheng (G/G) and 2.44% of speciments collected in Tanghe (S/S). Significantly higher G119S allele frequencies were observed in both propoxur- and malathion-resistant mosquitoes than in their sensitive counterparts in the Tanghe population (P < 0.05). Three mutations, L1014F (41.38%), L1014C (9.15%) and L1014W (0.12%), were detected in the kdr gene. The genotypes with the highest frequency in the populations of An. sinensis in Xiangfu and Tanghe were the mutant TTT (F/F) and wild-type TTG (L/L), at 67.86% (57/84) and 74.29% (52/70), respectively. In Pingqiao and Xiangfu, higher frequencies of the L1014F allele and lower frequencies of the L1014C allele were observed in mosquitoes resistant for beta-cyfluthrin than in those which were sensitive for this insecticide (P < 0.05). The results of Tajima's D and of Fu and Li's D and F were not significantly negative (P > 0.10), and each haplotype was interlaced and did not form two distinct branches. CONCLUSIONS High resistance to pyrethroids and propoxur was observed at four sites, but the resistance to malathion varied according to the location. Anopheles belenrae and the L1014W (TGG) mutation in An. sinensis were first discovered in Henan Province. The deltamethrin-resistant and deltamethrin-sensitive mosquito populations showed no genetic differentiation. The generation of resistance might be the result of the combination of multiple factors.
Collapse
Affiliation(s)
- Zhi-Quan He
- Department of Parasite Disease Control and Prevention, Henan Center for Disease Control and Prevention, Zhengzhou, China
- Henan Provincial Medical Key Laboratory of Parasitic Pathogen and Vector, No. 105 South Agricultural Road, Zhengdong New District, Zhengzhou, 450016, China
| | - Ya-Bo Hu
- Zhengzhou Second Hospital, No. 90 Hanghai Middle Road, Erqi District, Zhengzhou, 450016, China
| | - Dan Wang
- Department of Parasite Disease Control and Prevention, Henan Center for Disease Control and Prevention, Zhengzhou, China
- Henan Provincial Medical Key Laboratory of Parasitic Pathogen and Vector, No. 105 South Agricultural Road, Zhengdong New District, Zhengzhou, 450016, China
| | - Yu-Ting Liu
- College of Public Health, Zhengzhou University, No.100 Science Avenue, High-Tech District, Zhengzhou, 450016, China
| | - Cheng-Yun Yang
- Department of Parasite Disease Control and Prevention, Henan Center for Disease Control and Prevention, Zhengzhou, China
- Henan Provincial Medical Key Laboratory of Parasitic Pathogen and Vector, No. 105 South Agricultural Road, Zhengdong New District, Zhengzhou, 450016, China
| | - Dan Qian
- Department of Parasite Disease Control and Prevention, Henan Center for Disease Control and Prevention, Zhengzhou, China
- Henan Provincial Medical Key Laboratory of Parasitic Pathogen and Vector, No. 105 South Agricultural Road, Zhengdong New District, Zhengzhou, 450016, China
| | - Rui-Min Zhou
- Department of Parasite Disease Control and Prevention, Henan Center for Disease Control and Prevention, Zhengzhou, China
- Henan Provincial Medical Key Laboratory of Parasitic Pathogen and Vector, No. 105 South Agricultural Road, Zhengdong New District, Zhengzhou, 450016, China
| | - De-Ling Lu
- Department of Parasite Disease Control and Prevention, Henan Center for Disease Control and Prevention, Zhengzhou, China
- Henan Provincial Medical Key Laboratory of Parasitic Pathogen and Vector, No. 105 South Agricultural Road, Zhengdong New District, Zhengzhou, 450016, China
| | - Su-Hua Li
- Department of Parasite Disease Control and Prevention, Henan Center for Disease Control and Prevention, Zhengzhou, China
- Henan Provincial Medical Key Laboratory of Parasitic Pathogen and Vector, No. 105 South Agricultural Road, Zhengdong New District, Zhengzhou, 450016, China
| | - Ying Liu
- Department of Parasite Disease Control and Prevention, Henan Center for Disease Control and Prevention, Zhengzhou, China.
- Henan Provincial Medical Key Laboratory of Parasitic Pathogen and Vector, No. 105 South Agricultural Road, Zhengdong New District, Zhengzhou, 450016, China.
| | - Hong-Wei Zhang
- Department of Parasite Disease Control and Prevention, Henan Center for Disease Control and Prevention, Zhengzhou, China.
- Henan Provincial Medical Key Laboratory of Parasitic Pathogen and Vector, No. 105 South Agricultural Road, Zhengdong New District, Zhengzhou, 450016, China.
| |
Collapse
|
6
|
Sun D, Chen Y, Wang L, Hu X, Wu Q, Liu Y, Liu P, Zeng X, Li S, Wang G, Zhang Y. Surveillance and Control of Malaria Vectors in Hainan Province, China from 1950 to 2021: A Retrospective Review. Trop Med Infect Dis 2023; 8:tropicalmed8030131. [PMID: 36977132 PMCID: PMC10051372 DOI: 10.3390/tropicalmed8030131] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Revised: 02/17/2023] [Accepted: 02/18/2023] [Indexed: 02/24/2023] Open
Abstract
Malaria is a serious mosquito-borne tropical disease impacting populations in tropical regions across the world. Malaria was previously hyperendemic in Hainan Province. Due to large-scale anti-malarial intervention, malaria elimination in the province was achieved in 2019. This paper reviews the literature on the ecology, bionomics, and control of malaria vectors in Hainan from 1951 to 2021. We searched PubMed, and the China national knowledge infrastructure (CNKI) database for relevant articles published and included three other important books published in Chinese or English in order to summarize research on species, distribution, vectorial capacity, ecology, the resistance of malaria vectors to insecticides, and malaria vector control in Hainan Province. A total of 239 references were identified, 79 of which met the criteria for inclusion in our review. A total of six references dealt with the salivary gland infection of Anophelines, six with vectorial capacity, 41 with mosquito species and distribution, seven with seasonality, three with blood preference, four with nocturnal activity, two with flight distance, 13 with resistance to insecticides, and 14 with vector control. Only 16 published papers met the criteria of addressing malaria vectors in Hainan over the last 10 years (2012–2021). Anopheles dirus and Anopheles minimus are primary malaria vectors, mainly distributed in the southern and central areas of Hainan. Indoor residual spraying with DDT and the use of ITNs with pyrethroid insecticides were the main interventions taken for malaria control. Previous studies on ecology, bionomics, and resistance of vectors provided scientific evidence for optimizing malaria vector control and contributed to malaria elimination in Hainan Province. We hope our study will contribute to preventing malaria reestablishment caused by imported malaria in Hainan. Research on malaria vectors should be updated to provide scientific evidence for malaria vector control strategies post-elimination as the ecology, bionomics, and resistance of vectors to insecticides may change with changes in the environment.
Collapse
Affiliation(s)
- Dingwei Sun
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention (Chinese Center for Tropical Diseases Research), NHC Key Laboratory of Parasite and Vector Biology, WHO Collaborating Center for Tropical Diseases, National Center for International Research on Tropical Diseases, Shanghai 200025, China
- Hainan Provincial Center for Disease Control and Prevention, Haikou 570203, China
| | - Yan Chen
- Hainan Provincial Center for Disease Control and Prevention, Haikou 570203, China
| | - Lu Wang
- Hainan Provincial Center for Disease Control and Prevention, Haikou 570203, China
| | - Ximin Hu
- Hainan Provincial Center for Disease Control and Prevention, Haikou 570203, China
| | - Qun Wu
- Hainan Provincial Center for Disease Control and Prevention, Haikou 570203, China
| | - Ying Liu
- Hainan Provincial Center for Disease Control and Prevention, Haikou 570203, China
| | - Puyu Liu
- Hainan Provincial Center for Disease Control and Prevention, Haikou 570203, China
| | - Xuexia Zeng
- Hainan Provincial Center for Disease Control and Prevention, Haikou 570203, China
| | - Shangan Li
- Hainan Provincial Center for Disease Control and Prevention, Haikou 570203, China
| | - Guangze Wang
- Hainan Provincial Center for Disease Control and Prevention, Haikou 570203, China
| | - Yi Zhang
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention (Chinese Center for Tropical Diseases Research), NHC Key Laboratory of Parasite and Vector Biology, WHO Collaborating Center for Tropical Diseases, National Center for International Research on Tropical Diseases, Shanghai 200025, China
- School of Global Health, Chinese Center for Tropical Diseases Research, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
- Correspondence:
| |
Collapse
|
7
|
Zhao Y, Aung PL, Ruan S, Win KM, Wu Z, Soe TN, Soe MT, Cao Y, Sattabongkot J, Kyaw MP, Cui L, Menezes L, Parker DM. Spatio-temporal trends of malaria incidence from 2011 to 2017 and environmental predictors of malaria transmission in Myanmar. Infect Dis Poverty 2023; 12:2. [PMID: 36709318 PMCID: PMC9883610 DOI: 10.1186/s40249-023-01055-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Accepted: 01/13/2023] [Indexed: 01/29/2023] Open
Abstract
BACKGROUND Myanmar bears the heaviest malaria burden in the Greater Mekong Subregion (GMS). This study assessed the spatio-temporal dynamics and environmental predictors of Plasmodium falciparum and Plasmodium vivax malaria in Myanmar. METHODS Monthly reports of malaria cases at primary health centers during 2011-2017 were analyzed to describe malaria distribution across Myanmar at the township and state/region levels by spatial autocorrelation (Moran index) and spatio-temporal clustering. Negative binomial generalized additive models identified environmental predictors for falciparum and vivax malaria, respectively. RESULTS From 2011 to 2017, there was an apparent reduction in malaria incidence in Myanmar. Malaria incidence peaked in June each year. There were significant spatial autocorrelation and clustering with extreme spatial heterogeneity in malaria cases and test positivity across the nation (P < 0.05). Areas with higher malaria incidence were concentrated along international borders. Primary clusters of P. falciparum persisted in western townships, while clusters of P. vivax shifted geographically over the study period. The primary cluster was detected from January 2011 to December 2013 and covered two states (Sagaing and Kachin). Annual malaria incidence was highest in townships with a mean elevation of 500‒600 m and a high variance in elevation (states with both high and low elevation). There was an apparent linear relationship between the mean normalized difference vegetative index and annual P. falciparum incidence (P < 0.05). CONCLUSION The decreasing trends reflect the significant achievement of malaria control efforts in Myanmar. Prioritizing the allocation of resources to high-risk areas identified in this study can achieve effective disease control.
Collapse
Affiliation(s)
- Yan Zhao
- grid.412449.e0000 0000 9678 1884Department of Immunology, College of Basic Medical Sciences, China Medical University, Shenyang, 110122 Liaoning China
| | - Pyae Linn Aung
- Myanmar Health Network Organization, Yangon, Myanmar ,grid.10223.320000 0004 1937 0490Mahidol Vivax Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Shishao Ruan
- grid.412449.e0000 0000 9678 1884Department of Immunology, College of Basic Medical Sciences, China Medical University, Shenyang, 110122 Liaoning China
| | - Kyawt Mon Win
- grid.415741.2Department of Public Health, Ministry of Health, NayPyiTaw, Myanmar
| | - Zifang Wu
- grid.412449.e0000 0000 9678 1884Department of Immunology, College of Basic Medical Sciences, China Medical University, Shenyang, 110122 Liaoning China
| | - Than Naing Soe
- grid.415741.2Department of Public Health, Ministry of Health, NayPyiTaw, Myanmar
| | - Myat Thu Soe
- Myanmar Health Network Organization, Yangon, Myanmar
| | - Yaming Cao
- grid.412449.e0000 0000 9678 1884Department of Immunology, College of Basic Medical Sciences, China Medical University, Shenyang, 110122 Liaoning China
| | - Jetsumon Sattabongkot
- grid.10223.320000 0004 1937 0490Mahidol Vivax Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | | | - Liwang Cui
- grid.170693.a0000 0001 2353 285XDivision of Infectious Diseases and International Medicine, Department of Internal Medicine, Morsani College of Medicine, University of South Florida, 3720 Spectrum Boulevard, Suite 304, Tampa, FL 33612 USA
| | - Lynette Menezes
- grid.170693.a0000 0001 2353 285XDivision of Infectious Diseases and International Medicine, Department of Internal Medicine, Morsani College of Medicine, University of South Florida, 3720 Spectrum Boulevard, Suite 304, Tampa, FL 33612 USA
| | - Daniel M. Parker
- grid.266093.80000 0001 0668 7243Department of Population Health and Disease Prevention, Department of Epidemiology, University of California, Irvine, USA
| |
Collapse
|
8
|
Aung PL, Win KM, Pumpaibool T. Malaria Preventive Practices among People Residing in Different Malaria-Endemic Settings in a Township of Myanmar: A Mixed-Methods Study. Trop Med Infect Dis 2022; 7:tropicalmed7110353. [PMID: 36355895 PMCID: PMC9692550 DOI: 10.3390/tropicalmed7110353] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2022] [Revised: 11/01/2022] [Accepted: 11/01/2022] [Indexed: 11/06/2022] Open
Abstract
Different villages in a township or an area exhibit different malaria endemicities. This study aimed to investigate malaria preventive practices among people residing in different villages with stratified malaria endemicity in a township in Myanmar. Quantitative data were collected using standardized questionnaires by conducting face-to-face interviews, and qualitative data were obtained through in-depth interviews using a guideline. Quantitative data were analyzed using descriptive statistics and logistic regression models, whereas thematic analysis was used to visualize qualitative data. A total of 360 respondents with similar characteristics participated in the quantitative study. Knowledge regarding malaria and the availability of health information exhibited insignificant differences. Malaria preventive practices were considerably poor among people from moderate- and high-endemic villages (p < 0.05). Adult male farmers or gold miners with low annual family incomes reported poor preventive practices in both moderate- and high-endemic groups. People could not practice some malaria preventive measures because of a lack of resources, e.g., a lack of mosquito repellents. To eliminate the disparities of preventive practices in different malaria-endemic settings, heath-awareness-raising activities should be increased, especially in moderate- and high-endemic villages.
Collapse
Affiliation(s)
- Pyae Linn Aung
- College of Public Health Sciences, Chulalongkorn University, Bangkok 10330, Thailand
- Myanmar Health Network Organization, Yangon 11091, Myanmar
| | - Kyawt Mon Win
- Department of Public Health, Ministry of Health, NayPyiTaw 15011, Myanmar
| | - Tepanata Pumpaibool
- College of Public Health Sciences, Chulalongkorn University, Bangkok 10330, Thailand
- Correspondence:
| |
Collapse
|