1
|
Ngoenklan R, Thanh Duong T, Duc Chinh V, Quang Thieu N, Hii J, Bangs MJ, Aum-Aung B, Suwonkerd W, Chareonviriyaphap T. Comparison of Vector Trapping Methods for Outdoor Biting Malaria Vector Surveillance in Thailand and Vietnam. JOURNAL OF MEDICAL ENTOMOLOGY 2022; 59:2139-2149. [PMID: 36208216 DOI: 10.1093/jme/tjac147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Indexed: 06/16/2023]
Abstract
The performances of the human-baited double net trap (HDNT) and the human-baited host decoy trap (HDT) methods were compared against the outdoor human landing catch (OHLC) method in Thailand and Vietnam. Two study sites were selected in each country: a rural village and a nearby forest setting. The three outdoor trap methods were rotated nightly between three set trapping positions, in a pre-assigned Latin square design. Volunteers were rotated following the trap rotation to avoid bias. The greatest number of adult mosquitoes was collected from the forest sites in both countries, showing Anopheles minimus (s.s.) Theobald (96.54%) and Anopheles dirus (s.s.) Peyton & Harrison (25.71%) as the primary malaria vectors in Thailand and Vietnam, respectively. At the Thai forest site, OHLC collected significantly more anopheline mosquitoes per trap night than HDNT and HDT, with mean ± standard error values of 14.17 ± 4.42, 4.83 ± 1.56, and 4.44 ± 1.45, respectively, whilst HDNT and HDT were significantly less productive at 0.34 times and 0.31 times, respectively, than OHLC in capturing anopheline mosquitoes. However, there were no significant differences among the three methods of trapping malaria vectors for the village site. At the Vietnamese forest site, HDNT achieved the highest performance in collecting Anopheline mosquitoes at 1.54 times compared to OHLC, but there was no significant difference between the two traps. The results suggested HDNT could be a possible alternative trap to OHLC in this area. Although HDT was less efficient at attracting Anopheline mosquitoes, it was highly efficient at trapping culicine mosquitoes.
Collapse
Affiliation(s)
- Ratchadawan Ngoenklan
- Department of Entomology, Faculty of Agriculture, Kasetsart University, Bangkok, Thailand
| | - Tran Thanh Duong
- Department of Entomology, National Institute of Malariology, Parasitology and Entomology, Hanoi, Vietnam
| | - Vu Duc Chinh
- Department of Entomology, National Institute of Malariology, Parasitology and Entomology, Hanoi, Vietnam
| | - Nguyen Quang Thieu
- Department of Entomology, National Institute of Malariology, Parasitology and Entomology, Hanoi, Vietnam
| | - Jeffrey Hii
- Malaria Consortium Asia, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
- College of Public Health, Medical and Veterinary Sciences, James Cook University, Townsville, Queensland, Australia
| | - Michael J Bangs
- Department of Entomology, Faculty of Agriculture, Kasetsart University, Bangkok, Thailand
- Public Health and Malaria Control Department, PT Freeport Indonesia, International SOS, Papua, Indonesia
| | - Boonserm Aum-Aung
- Division of Vector Borne Diseases, Department of Disease Control, Ministry of Public Health, Nonthaburi, Thailand
| | - Wannapa Suwonkerd
- Division of Vector Borne Diseases, Department of Disease Control, Ministry of Public Health, Nonthaburi, Thailand
| | - Theeraphap Chareonviriyaphap
- Department of Entomology, Faculty of Agriculture, Kasetsart University, Bangkok, Thailand
- Royal Society of Thailand, Bangkok, Thailand
| |
Collapse
|
2
|
Tomas T, Eligo N, Tamiru G, Massebo F. Outdoor and early hour human biting activities of malaria mosquitoes and the suitability of clay pot for outdoor resting mosquito collection in malaria endemic villages of southern Rift Valley, Ethiopia. Parasite Epidemiol Control 2022; 19:e00278. [PMID: 36345433 PMCID: PMC9636569 DOI: 10.1016/j.parepi.2022.e00278] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2021] [Revised: 08/21/2022] [Accepted: 10/26/2022] [Indexed: 11/07/2022] Open
Abstract
Background Sampling adult Anopheles mosquitoes is important for assessing vector density, estimating the sporozoite infection rate, and quantifying the impact of vector control interventions. The objective of this study was to assess the Anopheles mosquito species composition, and their outdoor and indoor biting activities, and to evaluate the suitability of clay pots for indoor and outdoor resting mosquito collections. Methods Two malaria-endemic villages in the Gamo zone were purposely selected. Forty clay pots were deployed for outdoor resting mosquitoes sampling and another forty for indoor resting sampling. Twenty pit shelters were constructed for outdoor resting mosquito collection. The human landing catch (HLC) technique was employed to collect indoor and outdoor host-seeking mosquitoes in two households in each village. Morphological identification of the Anopheles mosquito was done using an identification key. Enzyme-linked immunosorbent assay technique was used for blood meal origin and circumsporozoite proteins (CSP) test. Speciation of An. gambiae complex was done using polymerase chain reaction. A Chi-square test was used to compare the effectiveness of clay pot and pit shelters for outdoor resting sampling. Results A total of 904 female Anopheles mosquitoes comprising An. gambiae complex, An. pharoensis, An. tenebrosus, An. dencalicus and An. demelloni were sampled. The majority (64%) of them were sampled by the HLC technique. There was a slight difference between the outdoor clay pot (19%) and pit shelter (17%) collection. No Anopheles mosquitoes were collected indoor using clay pots. All mosquitoes were tested for CSPs, but none of them were found to be positive. Anopheles mosquitoes were tending to bite humans outdoor than indoors, and their peak biting hours was 10–11 pm. The human blood meal index of Anopheles mosquitoes was 0.07 from pit shelters and it was 0.04 from clay pots. The bovine blood meal index was 0.45 for mosquitoes from both pit shelters and clay pot collections. Conclusion Anopheles arabiensis was the predominant species and it was tending to bite cattle more than humans. Clay pot could be suitable for outdoor resting mosquito collection, but not for indoor resting species.
Collapse
|
3
|
Whittaker C, Winskill P, Sinka M, Pironon S, Massey C, Weiss DJ, Nguyen M, Gething PW, Kumar A, Ghani A, Bhatt S. A novel statistical framework for exploring the population dynamics and seasonality of mosquito populations. Proc Biol Sci 2022; 289:20220089. [PMID: 35414241 PMCID: PMC9006040 DOI: 10.1098/rspb.2022.0089] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Understanding the temporal dynamics of mosquito populations underlying vector-borne disease transmission is key to optimizing control strategies. Many questions remain surrounding the drivers of these dynamics and how they vary between species-questions rarely answerable from individual entomological studies (that typically focus on a single location or species). We develop a novel statistical framework enabling identification and classification of time series with similar temporal properties, and use this framework to systematically explore variation in population dynamics and seasonality in anopheline mosquito time series catch data spanning seven species, 40 years and 117 locations across mainland India. Our analyses reveal pronounced variation in dynamics across locations and between species in the extent of seasonality and timing of seasonal peaks. However, we show that these diverse dynamics can be clustered into four 'dynamical archetypes', each characterized by distinct temporal properties and associated with a largely unique set of environmental factors. Our results highlight that a range of environmental factors including rainfall, temperature, proximity to static water bodies and patterns of land use (particularly urbanicity) shape the dynamics and seasonality of mosquito populations, and provide a generically applicable framework to better identify and understand patterns of seasonal variation in vectors relevant to public health.
Collapse
Affiliation(s)
- Charles Whittaker
- MRC Centre for Global Infectious Disease Analysis, School of Public Health, Imperial College, London, UK
| | - Peter Winskill
- MRC Centre for Global Infectious Disease Analysis, School of Public Health, Imperial College, London, UK
| | | | | | - Claire Massey
- Big Data Institute, University of Oxford, Old Road Campus, Oxford, UK
| | - Daniel J Weiss
- Malaria Atlas Project, Telethon Kids Institute, Perth Children's Hospital, Nedlands, WA 6009, Australia.,School of Public Health, Curtin University, Bentley, WA 6102, Australia
| | - Michele Nguyen
- Asian School of the Environment, Nanyang Technological University, Singapore, Singapore
| | - Peter W Gething
- Malaria Atlas Project, Telethon Kids Institute, Perth Children's Hospital, Nedlands, WA 6009, Australia.,School of Public Health, Curtin University, Bentley, WA 6102, Australia
| | - Ashwani Kumar
- Vector Control Research Centre, Indira Nagar, Puducherry, India
| | - Azra Ghani
- MRC Centre for Global Infectious Disease Analysis, School of Public Health, Imperial College, London, UK
| | - Samir Bhatt
- MRC Centre for Global Infectious Disease Analysis, School of Public Health, Imperial College, London, UK.,Section of Epidemiology, Department of Public Health, University of Copenhagen, Copenhagen, Denmark
| |
Collapse
|