1
|
Banik R, Islam MS, Mubarak M, Rahman M, Gesesew HA, Ward PR, Sikder MT. Public knowledge, belief, and preventive practices regarding dengue: Findings from a community-based survey in rural Bangladesh. PLoS Negl Trop Dis 2023; 17:e0011778. [PMID: 38060613 PMCID: PMC10754436 DOI: 10.1371/journal.pntd.0011778] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Revised: 12/28/2023] [Accepted: 11/07/2023] [Indexed: 12/29/2023] Open
Abstract
BACKGROUND Dengue fever, the most prevalent mosquito-borne viral infection, is a recurrent public health threat in Bangladesh. Despite the government's efforts, dengue outbreaks are on the upswing, and people's knowledge, belief, and preventive practices regarding the disease at the rural community level are unclear. OBJECTIVE The objective of this study was to assess the level of knowledge, belief and preventive practices regarding dengue and associated factors among community people from rural Bangladesh. METHODS A cross-sectional survey was conducted involving 401 people using a convenient sampling technique from three unions of Savar from August to September 2021. Participants' responses were collected through face-to-face interviews using a pre-tested structured questionnaire that included information related to socio-demographics, dengue-related knowledge, preventive practices, and the health belief model (HBM) constructs. Multiple linear regression analysis was performed to determine the factors associated with the knowledge and preventive practices of dengue. RESULTS Overall, participants (mean age = 33.47 ± 12.96 years; age range = 18-75 years) correctly answered 66.15% of the knowledge questions regarding dengue. Higher education, travel to dengue-risk regions, and self-efficacy under the HBM construct were all shown to be strongly associated with dengue knowledge. Regarding HBM constructs, about 80% of the participants perceived dengue as dangerous, but less than half (41.4%) believed themselves susceptible to dengue. Considering perceived barriers, 73.07% of the participants believed their residential area was not suitable for Aedes mosquito breeding. Nearly all (93.52%) believed they always kept their surrounding area clean as part of self-efficacy. Moreover, on average participants engaged in 53.69% of all dengue preventive practices. Being older, female, having a higher education, being a service holder, having a good quality of house structure, and perceived susceptibility as well as self-efficacy under the HBM construct were all factors in participants' dengue prevention activities. Participants' dengue preventative practices were shown to be significantly influenced by their knowledge. CONCLUSIONS The findings of this study found a moderate level of knowledge regarding dengue among the participants. Regarding dengue prevention, although participants scored highly in several indicators, the overall preventive practices were not satisfactory. This suggests that there is a pressing need for expanded education outreach aimed at increasing public awareness of dengue and encourage preventive practices within rural communities in Bangladesh.
Collapse
Affiliation(s)
- Rajon Banik
- Department of Public Health and Informatics, Jahangirnagar University, Savar, Dhaka-1342, Bangladesh
| | - Md. Saiful Islam
- Department of Public Health and Informatics, Jahangirnagar University, Savar, Dhaka-1342, Bangladesh
| | - Mahfuza Mubarak
- Department of Public Health and Informatics, Jahangirnagar University, Savar, Dhaka-1342, Bangladesh
| | - Mahmudur Rahman
- Department of Public Health and Informatics, Jahangirnagar University, Savar, Dhaka-1342, Bangladesh
| | - Hailay Abrha Gesesew
- College of Medicine and Public Health, Flinders University, Adelaide, South Australia, Australia
- Department of Epidemiology, School of Health Sciences, Mekelle University, Mekelle, Ethiopia
| | - Paul R. Ward
- Centre for Research on Health Policy, Torrens University Australia, Adelaide, South Australia, Australia
| | - Md. Tajuddin Sikder
- Department of Public Health and Informatics, Jahangirnagar University, Savar, Dhaka-1342, Bangladesh
| |
Collapse
|
2
|
Fu JYL, Chua CL, Abu Bakar AS, Vythilingam I, Wan Sulaiman WY, Alphey L, Chan YF, Sam IC. Susceptibility of Aedes albopictus, Ae. aegypti and human populations to Ross River virus in Kuala Lumpur, Malaysia. PLoS Negl Trop Dis 2023; 17:e0011423. [PMID: 37307291 DOI: 10.1371/journal.pntd.0011423] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Accepted: 05/28/2023] [Indexed: 06/14/2023] Open
Abstract
BACKGROUND Emerging arboviruses such as chikungunya and Zika viruses have unexpectedly caused widespread outbreaks in tropical and subtropical regions recently. Ross River virus (RRV) is endemic in Australia and has epidemic potential. In Malaysia, Aedes mosquitoes are abundant and drive dengue and chikungunya outbreaks. We assessed risk of an RRV outbreak in Kuala Lumpur, Malaysia by determining vector competence of local Aedes mosquitoes and local seroprevalence as a proxy of human population susceptibility. METHODOLOGY/PRINCIPAL FINDINGS We assessed oral susceptibility of Malaysian Ae. aegypti and Ae. albopictus by real-time PCR to an Australian RRV strain SW2089. Replication kinetics in midgut, head and saliva were determined at 3 and 10 days post-infection (dpi). With a 3 log10 PFU/ml blood meal, infection rate was higher in Ae. albopictus (60%) than Ae. aegypti (15%; p<0.05). Despite similar infection rates at 5 and 7 log10 PFU/ml blood meals, Ae. albopictus had significantly higher viral loads and required a significantly lower median oral infectious dose (2.7 log10 PFU/ml) than Ae. aegypti (4.2 log10 PFU/ml). Ae. albopictus showed higher vector competence, with higher viral loads in heads and saliva, and higher transmission rate (RRV present in saliva) of 100% at 10 dpi, than Ae. aegypti (41%). Ae. aegypti demonstrated greater barriers at either midgut escape or salivary gland infection, and salivary gland escape. We then assessed seropositivity against RRV among 240 Kuala Lumpur inpatients using plaque reduction neutralization, and found a low rate of 0.8%. CONCLUSIONS/SIGNIFICANCE Both Ae. aegypti and Ae. albopictus are susceptible to RRV, but Ae. albopictus displays greater vector competence. Extensive travel links with Australia, abundant Aedes vectors, and low population immunity places Kuala Lumpur, Malaysia at risk of an imported RRV outbreak. Surveillance and increased diagnostic awareness and capacity are imperative to prevent establishment of new arboviruses in Malaysia.
Collapse
Affiliation(s)
- Jolene Yin Ling Fu
- Department of Medical Microbiology, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, Malaysia
| | - Chong Long Chua
- Department of Medical Microbiology, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, Malaysia
| | | | - Indra Vythilingam
- Department of Parasitology, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, Malaysia
| | | | - Luke Alphey
- Arthropod Genetics Group, The Pirbright Institute, Woking, United Kingdom
| | - Yoke Fun Chan
- Department of Medical Microbiology, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, Malaysia
| | - I-Ching Sam
- Department of Medical Microbiology, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, Malaysia
| |
Collapse
|
3
|
Pimid M, Krishnan KT, Ahmad AH, Mohd Naim D, Chambers GK, Mohd Nor SA, Ab Majid AH. Parentage Assignment Using Microsatellites Reveals Multiple Mating in Aedes aegypti (Diptera: Culicidae): Implications for Mating Dynamics. JOURNAL OF MEDICAL ENTOMOLOGY 2022; 59:1525-1533. [PMID: 35733165 DOI: 10.1093/jme/tjac081] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/03/2022] [Indexed: 06/15/2023]
Abstract
The mosquito Aedes aegypti is the primary vector of the dengue, yellow fever, and chikungunya viruses. Evidence shows that Ae. aegypti males are polyandrous whereas Ae. aegypti females are monandrous in mating. However, the degree to which Ae. aegypti males and females can mate with different partners has not been rigorously tested. Therefore, this study examined the rates of polyandry via parentage assignment in three sets of competitive mating experiments using wild-type male and female Ae. aegypti. Parentage assignment was monitored using nine microsatellite DNA markers. All Ae. aegypti offspring were successfully assigned to parents with 80% or 95% confidence using CERVUS software. The results showed that both male and female Ae. aegypti mated with up to 3-4 different partners. Adults contributed differentially to the emergent offspring, with reproductive outputs ranging from 1 to 25 viable progeny. This study demonstrates a new perspective on the capabilities of male and female Ae. aegypti in mating. These findings are significant because successful deployment of reproductive control methods using genetic modification or sterile Ae. aegypti must consider the following criteria regarding their mating fitness: 1) choosing Ae. aegypti males that can mate with many different females; 2) testing how transformed Ae. aegypti male perform with polyandrous females; and 3) prioritizing the selection of polyandrous males and/or females Ae. aegypti that have the most offspring.
Collapse
Affiliation(s)
- Marcela Pimid
- Faculty of Agro Based Industry, Universiti Malaysia Kelantan, Jeli Campus, 17600 Kelantan, Malaysia
- School of Biological Sciences, Universiti Sains Malaysia, 11800 Penang, Malaysia
| | - Kumara Thevan Krishnan
- Faculty of Agro Based Industry, Universiti Malaysia Kelantan, Jeli Campus, 17600 Kelantan, Malaysia
| | - Abu Hassan Ahmad
- School of Biological Sciences, Universiti Sains Malaysia, 11800 Penang, Malaysia
| | - Darlina Mohd Naim
- School of Biological Sciences, Universiti Sains Malaysia, 11800 Penang, Malaysia
| | - Geoffrey K Chambers
- School of Biological Sciences, Victoria University of Wellington, PO Box 600, 6140 Wellington, New Zealand
| | - Siti Azizah Mohd Nor
- Institute of Marine Biotechnology, Universiti Malaysia Terengganu, 21030 Terengganu, Malaysia
| | - Abdul Hafiz Ab Majid
- Household & Structural Urban Entomology Laboratory, Vector Control Research Unit, School of Biological Sciences, Universiti Sains Malaysia, 11800 Penang, Malaysia
| |
Collapse
|
4
|
Cui G, Zhong S, Zheng T, Li Z, Zhang X, Li C, Hemming-Schroeder E, Zhou G, Li Y. Aedes albopictus life table: environment, food, and age dependence survivorship and reproduction in a tropical area. Parasit Vectors 2021; 14:568. [PMID: 34743753 PMCID: PMC8573987 DOI: 10.1186/s13071-021-05081-x] [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: 06/12/2021] [Accepted: 10/26/2021] [Indexed: 11/29/2022] Open
Abstract
Background Environmental conditions affect the biology of mosquito vectors. Aedes albopictus is a major vector of many important diseases including dengue, Zika, and chikungunya in China. Understanding the development, fecundity, and survivorship of Ae. albopictus mosquitoes in different environmental conditions is beneficial for the implementation of effective vector control measures. Methods Aedes albopictus larval and adult life-table experiments were conducted under natural conditions in indoor, half-shaded, and fully shaded settings, simulating the three major habitat types in Hainan Province, a tropical island in the South China Sea. Temperature, humidity, and light intensity were recorded daily. Larval rearing used habitat water and tap water, with and without additional artificial food. Development time, survivorship, pupation rate, and adult emergence rates were monitored. Adult mosquito survivorship and fecundity were monitored daily and reproductive rates were determined, and age-dependent survivorship and reproduction were analyzed. Results The pupation time and male and female emergence times were significantly shorter in indoor conditions than in shaded and half-shaded conditions for both tap water with added food and habitat water with added food groups. For habitat water with added food, the shaded environment had the lowest pupation rate among the settings. For tap water with added food group, the shaded environment had the lowest pupation rate. The mean survival time of females was 27.3 ± 0.8 days in the indoor condition, which was significantly longer than that in the half-shaded (18.4 ± 0.6 days) and shaded (13.8 ± 1.2 days) conditions. Adult mortality was age-dependent, and the rate of change in mortality with age was not significantly different among different environmental conditions. The mean net replacement rate (R0) of female mosquitoes showed no significant difference among the three conditions, whereas the per capita intrinsic growth rate (r) in the shaded condition was 42.0% and 20.4% higher than that in the indoor and half-shaded conditions, respectively. Female daily egg mass was also age-dependent in all the settings, decaying exponentially with age. Conclusions Our results imply that half-shaded conditions are likely the best natural condition for adult emergence and female reproduction, and food supply is crucial for larval development and pupation. The results provide new avenues for integrated mosquito management in indoor and outdoor areas, especially in half-shaded areas. Graphical Abstract ![]()
Supplementary Information The online version contains supplementary material available at 10.1186/s13071-021-05081-x.
Collapse
Affiliation(s)
- Guzhen Cui
- Key Laboratory of Tropical Translational Medicine of Ministry of Education, Hainan Medical University, Haikou, 571199, China.,Key Laboratory of Medical Microbiology and Parasitology of Education Department of Guizhou, School of Basic Medical Science, Guizhou Medical University, Guiyang, 550025, China
| | - Saifeng Zhong
- Department of Pathogen Biology, Hainan Medical University, Haikou, 571199, China
| | - Tuquan Zheng
- Department of Pathogen Biology, Hainan Medical University, Haikou, 571199, China
| | - Zhangrui Li
- Department of Pathogen Biology, Hainan Medical University, Haikou, 571199, China
| | - Xu Zhang
- Department of Pathogen Biology, Hainan Medical University, Haikou, 571199, China
| | - Chuang Li
- Department of Pathogen Biology, Hainan Medical University, Haikou, 571199, China
| | - Elizabeth Hemming-Schroeder
- Program in Public Health, College of Health Sciences, University of California at Irvine, Irvine, CA, 92617, USA
| | - Guofa Zhou
- Program in Public Health, College of Health Sciences, University of California at Irvine, Irvine, CA, 92617, USA.
| | - Yiji Li
- Key Laboratory of Tropical Translational Medicine of Ministry of Education, Hainan Medical University, Haikou, 571199, China. .,Department of Pathogen Biology, Hainan Medical University, Haikou, 571199, China. .,Hainan Medical University-The University of Hong Kong Joint Laboratory of Tropical Infectious Diseases, Hainan Medical University, Haikou, 571199, China.
| |
Collapse
|
5
|
Ong SQ, Ahmad H, Mohd Ngesom AM. Implications of the COVID-19 Lockdown on Dengue Transmission in Malaysia. Infect Dis Rep 2021; 13:148-160. [PMID: 33562890 PMCID: PMC7985789 DOI: 10.3390/idr13010016] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 01/28/2021] [Accepted: 02/01/2021] [Indexed: 11/30/2022] Open
Abstract
We aim to investigate the effect of large-scale human movement restrictions during the COVID-19 lockdown on both the dengue transmission and vector occurrences. This study compared the weekly dengue incidences during the period of lockdown to the previous years (2015 to 2019) and a Seasonal Autoregressive Integrated Moving Average (SARIMA) model that expected no movement restrictions. We found that the trend of dengue incidence during the first two weeks (stage 1) of lockdown decreased significantly with the incidences lower than the lower confidence level (LCL) of SARIMA. By comparing the magnitude of the gradient of decrease, the trend is 319% steeper than the trend observed in previous years and 650% steeper than the simulated model, indicating that the control of population movement did reduce dengue transmission. However, starting from stage 2 of lockdown, the dengue incidences demonstrated an elevation and earlier rebound by four weeks and grew with an exponential pattern. We revealed that Aedes albopictus is the predominant species and demonstrated a strong correlation with the locally reported dengue incidences, and therefore we proposed the possible diffusive effect of the vector that led to a higher acceleration of incidence rate.
Collapse
Affiliation(s)
- Song-Quan Ong
- CPUS, UOW Malaysia KDU Penang University College, 32, Jalan Anson, George Town 10400, Malaysia
- School of Computer Sciences, Universiti Sains Malaysia, Gelugor 11800, Malaysia
- Correspondence:
| | - Hamdan Ahmad
- Vector Control Research Unit, School of Biological Sciences, Universiti Sains Malaysia, Gelugor 11800, Malaysia;
| | - Ahmad Mohiddin Mohd Ngesom
- Faculty of Health Science, Universiti Kebangsaan Malaysia, Jalan Raja Muda Abdul Aziz, Kuala Lumpur 50300, Malaysia;
| |
Collapse
|
6
|
Marina CF, Bond JG, Hernández-Arriaga K, Valle J, Ulloa A, Fernández-Salas I, Carvalho DO, Bourtzis K, Dor A, Williams T, Liedo P. Population Dynamics of Aedes aegypti and Aedes albopictus in Two Rural Villages in Southern Mexico: Baseline Data for an Evaluation of the Sterile Insect Technique. INSECTS 2021; 12:58. [PMID: 33440870 PMCID: PMC7827525 DOI: 10.3390/insects12010058] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Revised: 01/06/2021] [Accepted: 01/07/2021] [Indexed: 12/11/2022]
Abstract
Indoor and outdoor ovitraps were placed in 15 randomly selected houses in two rural villages in Chiapas, southern Mexico. In addition, ovitraps were placed in five transects surrounding each village, with three traps per transect, one at the edge, one at 50 m, and another at 100 m from the edge of the village. All traps were inspected weekly. A transect with eight traps along a road between the two villages was also included. Population fluctuations of Aedes aegypti and Ae. albopictus were examined during 2016-2018 by counting egg numbers. A higher number of Aedes spp. eggs was recorded at Hidalgo village with 257,712 eggs (60.9%), of which 58.1% were present in outdoor ovitraps and 41.9% in indoor ovitraps, compared with 165,623 eggs (39.1%) collected in the village of Río Florido, 49.0% in outdoor and 51.0% in indoor ovitraps. A total of 84,047 eggs was collected from ovitraps placed along transects around Río Florido, compared to 67,542 eggs recorded from transects around Hidalgo. Fluctuations in egg counts were associated with annual variation in precipitation, with 2.3 to 3.2-fold more eggs collected from ovitraps placed in houses and 4.8 to 5.1-fold more eggs in ovitraps from the surrounding transects during the rainy season than in the dry season, respectively. Aedes aegypti was the dominant species during the dry season and at the start of the rainy season in both villages. Aedes albopictus populations were lower for most of the dry season, but increased during the rainy season and predominated at the end of the rainy season in both villages. Aedes albopictus was also the dominant species in the zones surrounding both villages. The numbers of eggs collected from intradomiciliary ovitraps were strongly correlated with the numbers of eggs in peridomiciliary ovitraps in both Río Florido (R2 adj = 0.92) and Hidalgo (R2 adj = 0.94), suggesting that peridomiciliary sampling could provide an accurate estimate of intradomiciliary oviposition by Aedes spp. in future studies in these villages. We conclude that the feasibility of sterile insect technique (SIT)-based program of vector control could be evaluated in the isolated Ae. aegypti populations in the rural villages of our baseline study.
Collapse
Affiliation(s)
- Carlos F. Marina
- Centro Regional de Investigación en Salud Pública-INSP, Tapachula, Chiapas 30700, Mexico; (J.G.B.); (K.H.-A.); (A.U.); (I.F.-S.)
| | - J. Guillermo Bond
- Centro Regional de Investigación en Salud Pública-INSP, Tapachula, Chiapas 30700, Mexico; (J.G.B.); (K.H.-A.); (A.U.); (I.F.-S.)
| | - Kenia Hernández-Arriaga
- Centro Regional de Investigación en Salud Pública-INSP, Tapachula, Chiapas 30700, Mexico; (J.G.B.); (K.H.-A.); (A.U.); (I.F.-S.)
| | - Javier Valle
- El Colegio de la Frontera Sur (ECOSUR), Tapachula, Chiapas 30700, Mexico; (J.V.); (A.D.); (P.L.)
| | - Armando Ulloa
- Centro Regional de Investigación en Salud Pública-INSP, Tapachula, Chiapas 30700, Mexico; (J.G.B.); (K.H.-A.); (A.U.); (I.F.-S.)
- Facultad de Ciencias Químicas, Universidad Autónoma de Chiapas (UNACH), Tapachula, Chiapas 30700, Mexico
| | - Ildefonso Fernández-Salas
- Centro Regional de Investigación en Salud Pública-INSP, Tapachula, Chiapas 30700, Mexico; (J.G.B.); (K.H.-A.); (A.U.); (I.F.-S.)
- Facultad de Ciencias Biológicas, Universidad Autónoma de Nuevo León (UANL), San Nicolás de los Garza, Nuevo León 66450, Mexico
| | - Danilo O. Carvalho
- Insect Pest Control Laboratory, Joint FAO/IAEA Programme of Nuclear Techniques in Food and Agriculture, IAEA Laboratories, 2444 Seibersdorf, Austria; (D.O.C.); (K.B.)
| | - Kostas Bourtzis
- Insect Pest Control Laboratory, Joint FAO/IAEA Programme of Nuclear Techniques in Food and Agriculture, IAEA Laboratories, 2444 Seibersdorf, Austria; (D.O.C.); (K.B.)
| | - Ariane Dor
- El Colegio de la Frontera Sur (ECOSUR), Tapachula, Chiapas 30700, Mexico; (J.V.); (A.D.); (P.L.)
| | - Trevor Williams
- Instituto de Ecología AC (INECOL), Xalapa, Veracruz 91073, Mexico;
| | - Pablo Liedo
- El Colegio de la Frontera Sur (ECOSUR), Tapachula, Chiapas 30700, Mexico; (J.V.); (A.D.); (P.L.)
| |
Collapse
|
7
|
Samuel PP, Govindarajan R, Krishnamoorthi R, Leo SVJ, Rajamannar V, Nagaraj J. Dengue infection among tribal population in the Nilgiris district, Tamil Nadu, India. J Vector Borne Dis 2021; 58:154-158. [DOI: 10.4103/0972-9062.328973] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
|
8
|
Lee J, Yek S, Wilson R, Rahman S. Characterization of the Aedes albopictus (Diptera: Culicidae) holobiome: bacterial composition across land use type and mosquito sex in Malaysia. Acta Trop 2020; 212:105683. [PMID: 32888935 DOI: 10.1016/j.actatropica.2020.105683] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Revised: 08/25/2020] [Accepted: 08/27/2020] [Indexed: 01/04/2023]
Abstract
Understanding the diversity and dynamics of the microbiota within the mosquito holobiome is of great importance to apprehend how the microbiota modulates various complex processes and interactions. This study examined the bacterial composition of Aedes albopictus across land use type and mosquito sex in the state of Selangor, Malaysia using 16S rRNA sequencing. The bacterial community structure in mosquitoes was found to be influenced by land use type and mosquito sex, with the environment and mosquito diet respectively identified to be the most likely sources of microbes. We found that approximately 70% of the microbiota samples were dominated by Wolbachia and removing Wolbachia from analyses revealed the relatively even composition of the remaining bacterial microbiota. Furthermore, microbial interaction network analysis highlighted the prevalence of co-exclusionary patterns in all networks regardless of land use and mosquito sex, with Wolbachia exhibiting co-exclusionary interactions with other residential bacteria such as Xanthomonas, Xenophilus and Zymobacter.
Collapse
|
9
|
Muhammad NAF, Abu Kassim NF, Ab Majid AH, Abd Rahman A, Dieng H, Avicor SW. Biting rhythm and demographic attributes of Aedes albopictus (Skuse) females from different urbanized settings in Penang Island, Malaysia under uncontrolled laboratory conditions. PLoS One 2020; 15:e0241688. [PMID: 33175896 PMCID: PMC7657491 DOI: 10.1371/journal.pone.0241688] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Accepted: 10/19/2020] [Indexed: 01/30/2023] Open
Abstract
Urbanization could potentially modify Aedes albopictus' ecology by changing the dynamics of the species, and affecting their breeding sites due to environmental changes, and thus contribute to dengue outbreaks. Thus, this study was conducted to evaluate the biting rhythm, fecundity and longevity of adult female Ae. albopictus in relation to urbanization strata; urban, suburban and rural areas in Penang Island, Malaysia. The experiments were done in comparison to a laboratory strain. Twenty-four hours biting activity of all the mosquito strains showed a clear bimodal biting activity, with morning and evening twilight peaks. The interaction effect between biting time and mosquito strains was not significant. Meanwhile, differences in fecundity among mosquito strains were statistically significant (F(3,442) = 10.559, P < 0.05) with urban areas having higher mean number of eggs (mean = 107.69, standard error = 3.98) than suburban (mean = 94.48, standard error = 5.18), and rural areas (mean = 72.52, standard error = 3.87). Longevity of adult females were significantly higher (F(3,441) = 31.259, P < 0.05) for mosquito strains from urban areas compared to the other strains. These findings would provide crucial information for the planning of control programs in Malaysia, particularly Penang.
Collapse
Affiliation(s)
| | - Nur Faeza Abu Kassim
- School of Biological Sciences, Universiti Sains Malaysia, Minden, Penang, Malaysia
- Vector Control Research Unit, School of Biological Sciences, Universiti Sains Malaysia, Minden, Penang, Malaysia
| | - Abdul Hafiz Ab Majid
- School of Biological Sciences, Universiti Sains Malaysia, Minden, Penang, Malaysia
- Household and Structural Urban Entomology Laboratory, Vector Control Research Unit (VCRU), School of Biological Sciences, Universiti Sains Malaysia, Minden, Penang, Malaysia
| | - Azimah Abd Rahman
- School of Humanities, Universiti Sains Malaysia, Minden, Penang, Malaysia
| | - Hamady Dieng
- Institute of Biodiversity and Environmental Conservation (IBEC), Universiti Malaysia Sarawak, Kota Samarahan, Sarawak, Malaysia
| | - Silas Wintuma Avicor
- Entomology Division, Cocoa Research Institute of Ghana (CRIG), New Tafo-Akim, Eastern Region, Ghana
| |
Collapse
|
10
|
Nikookar SH, Fazeli-Dinan M, Enayati A, Zaim M. Zika; a continuous global threat to public health. ENVIRONMENTAL RESEARCH 2020; 188:109868. [PMID: 32846650 DOI: 10.1016/j.envres.2020.109868] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 06/22/2020] [Accepted: 06/22/2020] [Indexed: 06/11/2023]
Abstract
Zika virus is transmitted by Aedes mosquitoes, especially, Ae. aegypti and Ae. albopictus. About 80% of the cases do not manifest any symptoms, and it is a self-limiting, mild viral infection. In 20% of the cases and only in fraction of those who do show the symptoms, important complications including Guillaine Barre'syndrome and microcephaly may occur. The emergence of Zika in 2016 in Brazil spreading to about 70 other countries prompted the WHO officials to declare the disease a Public Health Emergency with International Concern (PHEIC). This has led to increased concerns in health authorities of almost all countries making them embark on the strengthened human and vector surveillance, vector control and clinical management of the disease. Although the main vectors of the disease have not yet been able to establish in Iran, because of their occurrence in neighboring countries as well as increased global travel and trade, the country established a national advisory committee for capacity building, vector and human surveillance and case management of Aedes-borne diseases. This study aims at performing a literature review about global situation of Zika and Aedes mosquitoes, their distribution, biology and ecology from the past to present and the threat posed to Iran. Aedes aegypti was historically present in the checklist of Iranian mosquitoes and Ae. albopictus has recently been collected from Southern Iran, however, the species has apparently failed to establish in the country as comprehensive follow up entomological surveillance could not reproduce the findings. Although Zika was not detected in Iran, considering the expansion in tourism, travel and trade to and from Zika infected and Aedes infested countries, suitable climate and favorable prediction for establishment of Aedes vectors, Iran may well be at risk of invasion of Aedes vector species and the diseases they carry. Therefore, this review is of value particularly to health authorities in Iran and other WHO Eastern Mediterranean countries for sustained vigilance and preparedness for early detection and response, including vector control.
Collapse
Affiliation(s)
- Seyed Hassan Nikookar
- Department of Medical Entomology and Vector Control, Health Sciences Research Center, Addiction Institute, School of Public Health, Mazandaran University of Medical Sciences, Sari, Iran
| | - Mahmoud Fazeli-Dinan
- Department of Medical Entomology and Vector Control, Health Sciences Research Center, Addiction Institute, School of Public Health, Mazandaran University of Medical Sciences, Sari, Iran
| | - Ahmadali Enayati
- Professor and Head of Medical Entomology Department, School of Public Health and Health Sciences Research Center, Mazandaran University of Medical Sciences, Sari, Iran.
| | - Morteza Zaim
- Department of Medical Entomology and Vector Control, School of Public Health, Tehran University of Medical Sciences, Iran
| |
Collapse
|
11
|
Vertical Infestation Profile of Aedes in Selected Urban High-Rise Residences in Malaysia. Trop Med Infect Dis 2020; 5:tropicalmed5030114. [PMID: 32646026 PMCID: PMC7557596 DOI: 10.3390/tropicalmed5030114] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Revised: 06/05/2020] [Accepted: 06/13/2020] [Indexed: 11/23/2022] Open
Abstract
Dengue is placing huge burdens on the Malaysian healthcare system as well as the economy. With the expansion in the number of high-rise residential buildings, particularly in the urban centers, the flight range and behavior of Aedes mosquitoes may be altered in this habitat type. In this study, we aimed to expand the understanding of the vertical distribution and dispersal of Aedes in nine selected high-rise residences in Kuala Lumpur, Selangor, and Johor using ovitraps as the sampling method. We discovered that Ae. aegypti is the predominant species in all study sites. Both Ae. aegypti and Ae. albopictus are most abundant within the first three levels and could be found up to level 21 (approximately 61.1–63.0 m). Pearson correlation analyses exhibited negative correlations in eight out of nine study sites between the ovitrap indexes (OIs) within each floor level, suggesting that Aedes density decreased as the building level increased. Our findings provide information to the public health authorities on ‘hot spot’ floors for effective suppression of dengue transmission.
Collapse
|
12
|
Metelmann S, Caminade C, Jones AE, Medlock JM, Baylis M, Morse AP. The UK's suitability for Aedes albopictus in current and future climates. J R Soc Interface 2020; 16:20180761. [PMID: 30862279 PMCID: PMC6451397 DOI: 10.1098/rsif.2018.0761] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The Asian tiger mosquito Aedes albopictus is able to transmit various pathogens to humans and animals and it has already caused minor outbreaks of dengue and chikungunya in southern Europe. Alarmingly, it is spreading northwards and its eggs have been found in the UK in 2016 and 2017. Climate-driven models can help to analyse whether this originally subtropical species could become established in northern Europe. But so far, these models have not considered the impact of the diurnal temperature range (DTR) experienced by mosquitoes in the field. Here, we describe a dynamical model for the life cycle of Ae. albopictus, taking into account the DTR, rainfall, photoperiod and human population density. We develop a new metric for habitat suitability and drive our model with different climate data sets to analyse the UK's suitability for this species. For now, most of the UK seems to be rather unsuitable, except for some densely populated and high importation risk areas in southeast England. But this picture changes in the next 50 years: future scenarios suggest that Ae. albopictus could become established over almost all of England and Wales, indicating the need for continued mosquito surveillance.
Collapse
Affiliation(s)
- S Metelmann
- 1 Institute for Infection and Global Health, University of Liverpool Liverpool , UK.,3 NIHR Health Protection Research Unit in Emerging and Zoonotic Infections , Liverpool , UK
| | - C Caminade
- 1 Institute for Infection and Global Health, University of Liverpool Liverpool , UK.,3 NIHR Health Protection Research Unit in Emerging and Zoonotic Infections , Liverpool , UK
| | - A E Jones
- 1 Institute for Infection and Global Health, University of Liverpool Liverpool , UK
| | - J M Medlock
- 3 NIHR Health Protection Research Unit in Emerging and Zoonotic Infections , Liverpool , UK.,4 Medical Entomology Group, Public Health England , London UK
| | - M Baylis
- 1 Institute for Infection and Global Health, University of Liverpool Liverpool , UK.,3 NIHR Health Protection Research Unit in Emerging and Zoonotic Infections , Liverpool , UK
| | - A P Morse
- 2 School of Environmental Sciences, University of Liverpool Liverpool , UK.,3 NIHR Health Protection Research Unit in Emerging and Zoonotic Infections , Liverpool , UK
| |
Collapse
|
13
|
Kache PA, Eastwood G, Collins-Palmer K, Katz M, Falco RC, Bajwa WI, Armstrong PM, Andreadis TG, Diuk-Wasser MA. Environmental Determinants of Aedes albopictus Abundance at a Northern Limit of Its Range in the United States. Am J Trop Med Hyg 2020; 102:436-447. [PMID: 31833467 PMCID: PMC7008348 DOI: 10.4269/ajtmh.19-0244] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Aedes albopictus is a vector of arboviruses with high rates of morbidity and mortality. The northern limit of Ae. albopictus in the northeastern United States runs through New York state (NYS) and Connecticut. We present a landscape-level analysis of mosquito abundance measured by daily counts of Ae. albopictus from 338 trap sites in 12 counties during May–September 2017. During the study period, the mean number of Ae. albopictus caught per day of trapping across all sites was 3.21. We constructed four sets of negative binomial generalized linear models to evaluate how trapping methodology, land cover, as well as temperature and precipitation at multiple time intervals influenced Ae. albopictus abundance. Biogents-Sentinel (BGS) traps were 2.78 times as efficient as gravid traps and 1.49 times as efficient as CO2-baited CDC light traps. Greater proportions of low- and medium-intensity development and low proportions of deciduous cover around the trap site were positively associated with increased abundance, as were minimum winter temperature and March precipitation. The cumulative precipitation within a 28-day time window before the date of collection had a nonlinear relationship with abundance, such that greater cumulative precipitation was associated with increased abundance until approximately 70 mm, above which there was a decrease in abundance. We concluded that populations are established in Nassau, Suffolk, and New York City counties in NYS; north of these counties, the species is undergoing population invasion and establishment. We recommend that mosquito surveillance programs monitoring the northward invasion of Ae. albopictus place BGS traps at sites chosen with respect to land cover.
Collapse
Affiliation(s)
- Pallavi A Kache
- Department of Ecology, Evolution, and Environmental Biology, Columbia University, New York City, New York
| | - Gillian Eastwood
- Center for Vector Biology & Zoonotic Diseases, Connecticut Agricultural Experiment Station, New Haven, Connecticut.,Department of Entomology, Virginia Polytechnic Institute and State University, Blacksburg, Virginia
| | - Kaitlin Collins-Palmer
- Department of Ecology, Evolution, and Environmental Biology, Columbia University, New York City, New York
| | - Marly Katz
- Bureau of Communicable Disease Control, New York State Department of Health, Albany, New York.,The Louis Calder Center-Biological Field Station, Fordham University, Armonk, New York
| | - Richard C Falco
- Bureau of Communicable Disease Control, New York State Department of Health, Albany, New York.,The Louis Calder Center-Biological Field Station, Fordham University, Armonk, New York
| | - Waheed I Bajwa
- Office of Vector Surveillance and Control, New York City Department of Health and Mental Hygiene, New York, New York
| | - Philip M Armstrong
- Center for Vector Biology & Zoonotic Diseases, Connecticut Agricultural Experiment Station, New Haven, Connecticut
| | - Theodore G Andreadis
- Center for Vector Biology & Zoonotic Diseases, Connecticut Agricultural Experiment Station, New Haven, Connecticut
| | - Maria A Diuk-Wasser
- Department of Ecology, Evolution, and Environmental Biology, Columbia University, New York City, New York
| |
Collapse
|
14
|
Incidence and epidemiological features of dengue in Sabah, Malaysia. PLoS Negl Trop Dis 2020; 14:e0007504. [PMID: 32392222 PMCID: PMC7241834 DOI: 10.1371/journal.pntd.0007504] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2019] [Revised: 05/21/2020] [Accepted: 12/19/2019] [Indexed: 12/22/2022] Open
Abstract
In South East Asia, dengue epidemics have increased in size and geographical distribution in recent years. We examined the spatiotemporal distribution and epidemiological characteristics of reported dengue cases in the predominantly rural state of Sabah, in Malaysian Borneo-an area where sylvatic and urban circulation of pathogens are known to intersect. Using a public health data set of routinely notified dengue cases in Sabah between 2010 and 2016, we described demographic and entomological risk factors, both before and after a 2014 change in the clinical case definition for the disease. Annual dengue incidence rates were spatially variable over the 7-year study period from 2010-2016 (state-wide mean annual incidence of 21 cases/100,000 people; range 5-42/100,000), but were highest in rural localities in the western districts of the state (Kuala Penyu, Nabawan, Tenom and Kota Marudu). Eastern districts exhibited lower overall dengue rates, although a high proportion of severe (haemorrhagic) dengue cases (44%) were focused in Sandakan and Tawau. Dengue incidence was highest for those aged between 10 and 29 years (24/100,000), and was slightly higher for males compared to females. Available vector surveillance data indicated that during large outbreaks in 2015 and 2016 the mosquito Aedes albopictus was more prevalent in both urban and rural households (House Index of 64%) than Ae. aegypti (15%). Demographic patterns remained unchanged both before and after the dengue case definition was changed; however, in the years following the change, reported case numbers increased substantially. Overall, these findings suggest that dengue outbreaks in Sabah are increasing in both urban and rural settings. Future studies to better understand the drivers of risk in specific age groups, genders and geographic locations, and to test the potential role of Ae. albopictus in transmission, may help target dengue prevention and control efforts.
Collapse
|
15
|
Verma S, Kumar N, Shiba, Choudhary P, Singhania K, Kumar M. Dengue awareness and its determinants among urban adults of Rohtak, Haryana. J Family Med Prim Care 2020; 9:2040-2044. [PMID: 32670962 PMCID: PMC7346910 DOI: 10.4103/jfmpc.jfmpc_1203_19] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2019] [Revised: 12/28/2019] [Accepted: 03/02/2020] [Indexed: 12/04/2022] Open
Abstract
Context: Despite so many efforts to control dengue, the disease has a huge impact on the health, well-being, and economy of the population. The key success to control dengue depends not only on services provided by health authorities but also on the awareness of the community about preventing practices and their health-seeking behavior. Hence, the present study was conducted to assess the awareness regarding dengue and its determinants among urban adult population of Rohtak. Aims: To assess the awareness regarding dengue and its determinants among urban adult population of Rohtak. Settings and Design: A cross-sectional study. Methods and Materials: Data were collected using a pretested, semi-structured interview schedule from 210 participants which included information on the demographic profile of the subject, awareness about the symptoms, transmission, vector behavior in terms of biting time and breeding places, preventive measures and treatment of dengue fever, and responsibility of vector control. Cumulative awareness was calculated on the basis of correct answers provided. Statistical Analysis Used: Categorical data were presented as a percentage. Pearson's Chi-square test was used to evaluate differences between groups for categorical variables. Results: The level of awareness was better among males (statistically significant). The difference in the level of awareness with respect to education, occupation, and the socioeconomic class was found highly statistically significant. Conclusions: Awareness regarding dengue and its preventive measures were specifically low in women; mostly housewives, in participants of the lower socioeconomic group, and those who were illiterate.
Collapse
|
16
|
Ali I, Mundle M, Anzinger JJ, Sandiford SL. Tiger in the sun: A report of Aedes albopictus in Jamaica. Acta Trop 2019; 199:105112. [PMID: 31351894 DOI: 10.1016/j.actatropica.2019.105112] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Revised: 07/24/2019] [Accepted: 07/24/2019] [Indexed: 11/15/2022]
Abstract
This report describes the presence of Aedes albopictus (Skuse) in Jamaica. The adults were found while conducting an ongoing survey of mosquitoes on the island. Specimens were collected using a combination of modified Center for Disease Control (CDC) miniature light traps and BG sentinel traps. A total of six adult female Ae. albopictus mosquitoes were collected at two different locations in October of 2018. This finding increases the number of Aedes mosquito species on the island bringing with it public health implications.
Collapse
Affiliation(s)
- Inshan Ali
- Department of Microbiology, Faculty of Medical Sciences, The University of the West Indies, Mona, Jamaica
| | | | - Joshua J Anzinger
- Department of Microbiology, Faculty of Medical Sciences, The University of the West Indies, Mona, Jamaica; Global Virus Network, Baltimore, Maryland, USA
| | - Simone L Sandiford
- Department of Basic Medical Sciences, Pharmacology and Pharmacy Section, Faculty of Medical Sciences, The University of the West Indies, Mona, Jamaica; Mosquito Control and Research Unit, The University of the West Indies, Mona, Jamaica.
| |
Collapse
|
17
|
Analysis of codon usage bias of Crimean-Congo hemorrhagic fever virus and its adaptation to hosts. INFECTION GENETICS AND EVOLUTION 2017; 58:1-16. [PMID: 29198972 DOI: 10.1016/j.meegid.2017.11.027] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2017] [Revised: 11/02/2017] [Accepted: 11/28/2017] [Indexed: 01/05/2023]
Abstract
Crimean-Congo hemorrhagic fever virus (CCHFV) is a negative-sense, single stranded RNA virus with a three-segmented genome that belongs to the genus Nairovirus within the family Bunyaviridae. CCHFV uses Hyalomma ticks as a vector to infect humans with a wide range of clinical signs, from asymptomatic to Zika-like syndrome. Despite significant progress in genomic analyses, the influences of viral relationships with different hosts on overall viral fitness, survival, and evading the host's immune systems remain unknown. To better understand the evolutionary characteristics of CCHFV, we performed a comprehensive analysis of the codon usage pattern in 179 CCHFV strains by calculating the relative synonymous codon usage (RSCU), effective number of codons (ENC), codon adaptation index (CAI), and other indicators. The results indicate that the codon usage bias of CCHFV is relatively low. Several lines of evidence support the hypothesis that a translation selection factor is shaping codon usage pattern in this virus. A correspondence analysis (CA) showed that other factors, such as base composition, aromaticity, and hydrophobicity may also be involved in shaping the codon usage pattern of CCHFV. Additionally, the results from a comparative analysis of RSCU between CCHFV and its hosts suggest that CCHFV tends to evolve codon usage patterns that are comparable to those of its hosts. Furthermore, the selection pressures from Homo sapiens, Bos taurus, and Ovis aries on the CCHFV RSCU patterns were dominant when compared with selection pressure from Hyalomma spp. vectors. Taken together, both natural selection and mutation pressure are important for shaping the codon usage pattern of CCHFV. We believe that such findings will assist researchers in understanding the evolution of CCHFV and its adaptation to its hosts.
Collapse
|
18
|
Rahim J, Ahmad AH, Ahmad H, Ishak IH, Rus AC, Maimusa HA. Adulticidal Susceptibility Evaluation of Aedes albopictus Using New Diagnostic Doses in Penang Island, Malaysia. JOURNAL OF THE AMERICAN MOSQUITO CONTROL ASSOCIATION 2017; 33:200-208. [PMID: 28854111 DOI: 10.2987/16-6607r.1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Insecticide-based vector control approaches are facing challenges due to the development of resistance in vector mosquitoes. Therefore, a proper resistance surveillance program using baseline lethal concentrations is crucial for resistance management strategies. Currently, the World Health Organization's (WHO) diagnostic doses established for Aedes aegypti and Anopheles species are being used to study the resistance status of Aedes albopictus. In this study, we established the diagnostic doses for permethrin, deltamethrin, and malathion using a known susceptible reference strain. Five field-collected populations were screened against these doses, following the WHO protocol. This study established the diagnostic dose of malathion at 2.4%, permethrin at 0.95%, and deltamethrin at 0.28%, which differ from the WHO doses for Aedes aegypti and Anopheles spp. Among the insecticides tested on the 5 wild populations, only deltamethrin showed high effectiveness. Different susceptibility and resistance patterns were observed with permethrin, malathion, and dichloro-diphenyl-trichloroethane (DDT) at 4%. This study may assist the health authorities to improve future chemical-based vector control operations in dengue-endemic areas.
Collapse
|
19
|
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.
Collapse
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
| |
Collapse
|
20
|
Dieng H, Ellias SB, Satho T, Ahmad AH, Abang F, Ghani IA, Noor S, Ahmad H, Zuharah WF, Morales Vargas RE, Morales NP, Hipolito CN, Attrapadung S, Noweg GT. Coffee, its roasted form, and their residues cause birth failure and shorten lifespan in dengue vectors. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2017; 24:14782-14794. [PMID: 28470499 DOI: 10.1007/s11356-017-8711-4] [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: 10/11/2016] [Accepted: 02/28/2017] [Indexed: 06/07/2023]
Abstract
In dengue mosquitoes, successful embryonic development and long lifespan are key determinants for the persistence of both virus and vector. Therefore, targeting the egg stage and vector lifespan would be expected to have greater impacts than larvicides or adulticides, both strategies that have lost effectiveness due to the development of resistance. Therefore, there is now a pressing need to find novel chemical means of vector control. Coffee contains many chemicals, and its waste, which has become a growing environmental concern, is as rich in toxicants as the green coffee beans; these chemicals do not have a history of resistance in insects, but some are lost in the roasting process. We examined whether exposure to coffee during embryonic development could alter larval eclosion and lifespan of dengue vectors. A series of bioassays with different coffee forms and their residues indicated that larval eclosion responses of Aedes albopictus and Ae. aegypti were appreciably lower when embryonic maturation occurred in environments containing coffee, especially roasted coffee crude extract (RCC). In addition, the lifespan of adults derived from eggs that hatched successfully in a coffee milieu was reduced, but this effect was less pronounced with roasted and green coffee extracts (RCU and GCU, respectively). Taken together, these findings suggested that coffee and its residues have embryocidal activities with impacts that are carried over onto the adult lifespan of dengue vectors. These effects may significantly reduce the vectorial capacity of these insects. Reutilizing coffee waste in vector control may also represent a realistic solution to the issues associated with its pollution.
Collapse
Affiliation(s)
- Hamady Dieng
- Institute of Biodiversity and Environmental Conservation (IBEC), Faculty of Resource Science and Technology, Universiti Malaysia Sarawak, Kota Samarahan, Malaysia.
| | | | - Tomomitsu Satho
- Faculty of Pharmaceutical Sciences, Fukuoka University, Fukuoka, Japan
| | - Abu Hassan Ahmad
- School of Biological Sciences, Universiti Sains Malaysia, Penang, Malaysia
| | - Fatimah Abang
- Faculty of Resource Science and Technology, Universiti Malaysia Sarawak, Kota Samarahan, Malaysia
| | - Idris Abd Ghani
- Faculty of Science and Technology, Universiti Kebangsaan Malaysia, Bangi, Malaysia
| | - Sabina Noor
- Faculty of Resource Science and Technology, Universiti Malaysia Sarawak, Kota Samarahan, Malaysia
| | - Hamdan Ahmad
- School of Biological Sciences, Universiti Sains Malaysia, Penang, Malaysia
| | - Wan Fatma Zuharah
- School of Biological Sciences, Universiti Sains Malaysia, Penang, Malaysia
| | | | | | - Cirilo N Hipolito
- Faculty of Resource Science and Technology, Universiti Malaysia Sarawak, Kota Samarahan, Malaysia
| | | | - Gabriel Tonga Noweg
- Institute of Biodiversity and Environmental Conservation (IBEC), Faculty of Resource Science and Technology, Universiti Malaysia Sarawak, Kota Samarahan, Malaysia
| |
Collapse
|
21
|
|
22
|
Johnson BJ, Hurst T, Quoc HL, Unlu I, Freebairn C, Faraji A, Ritchie SA. Field Comparisons of the Gravid Aedes Trap (GAT) and BG-Sentinel Trap for Monitoring Aedes albopictus (Diptera: Culicidae) Populations and Notes on Indoor GAT Collections in Vietnam. JOURNAL OF MEDICAL ENTOMOLOGY 2017; 54:340-348. [PMID: 27707983 DOI: 10.1093/jme/tjw166] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2016] [Accepted: 09/14/2016] [Indexed: 06/06/2023]
Abstract
We report on the use of the Gravid Aedes Trap (GAT) as a surveillance device for Aedes albopictus (Skuse) relative to the BG-Sentinel (BGS) trap in field studies conducted in Trenton, NJ, and on Hammond Island, Queensland, Australia. A parallel study conducted in Nha Trang, Vietnam, assessed the use of the GAT as an indoor surveillance device as well as the use of canola oil as a noninsecticide killing agent. In Trenton and Hammond Island, the GAT collected fewer male (0.40 ± 0.12 and 0.43 ± 0.30, respectively) and female (3.05 ± 0.67 and 2.7 ± 2.3, respectively) Ae. albopictus than the BGS trap (males: 3.54 ± 1.26 and 3.75 ± 0.83; females: 4.66 ± 1.18 and 3.9 ± 0.23) over their respective sampling periods (i.e., 24 h for the BGS and 1 wk for the GAT). Despite differences in capture rates, the percentage of traps positive for female Ae. albopictus was similar between the BGS and GAT (Trenton: 60.1 ± 6.3% and 64.4 ± 4.1%; Hammond: 87.5 ± 6.9% and 80.0 ± 8.2%). In Nha Trang, the GAT was equally effective indoors and outdoors with (10 g hay or 3 g fish food) and without (water or empty) infusion. Additionally, no significant decrease in collections was observed between GATs set with canola oil or long-lasting insecticidal net. In summary, both traps were successful in monitoring female Ae. albopictus over their respective trapping intervals, but would be best used to complement each other to monitor both sexes and all physiological stages of female Ae. albopictus. However, the versatility and low-cost of the GAT makes it an attractive alternative to the more expensive BGS trap.
Collapse
Affiliation(s)
- Brian J Johnson
- College of Public Health, Medical and Veterinary Sciences, James Cook University, PO Box 6811, Cairns, Queensland 4870, Australia ( ; )
- Australian Institute of Tropical Health and Medicine, James Cook University, PO Box 6811, Cairns, Queensland 4870, Australia
| | - Tim Hurst
- Australian Foundation for Peoples of Asia and the Pacific Limited, Hanoi, Vietnam
| | - Hung Luu Quoc
- National Institute of Hygiene and Epidemiology, Hanoi, Vietnam
| | - Isik Unlu
- Mercer County Mosquito Commission, West Trenton, NJ
- Center for Vector Biology, Rutgers University, 180 Jones Ave., New Brunswick, NJ
| | | | - Ary Faraji
- Salt Lake City Mosquito Abatement District, 2020 North Redwood Rd., Salt Lake City, UT
| | - Scott A Ritchie
- College of Public Health, Medical and Veterinary Sciences, James Cook University, PO Box 6811, Cairns, Queensland 4870, Australia ( ; )
- Australian Institute of Tropical Health and Medicine, James Cook University, PO Box 6811, Cairns, Queensland 4870, Australia
| |
Collapse
|
23
|
Contribution of public places in proliferation of dengue vectors in Penang Island, Malaysia. Asian Pac J Trop Biomed 2017. [DOI: 10.1016/j.apjtb.2016.12.017] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
|
24
|
Adilah-Amrannudin N, Hamsidi M, Ismail NA, Ismail R, Dom NC, Ahmad AH, Mastuki MF, Basri TSATA, Khalid A, Muslim M, Daud NAA, Camalxaman SN. Genetic Polymorphism of Aedes albopictus Population Inferred From ND5 Gene Variabilities In Subang Jaya, Malaysia. JOURNAL OF THE AMERICAN MOSQUITO CONTROL ASSOCIATION 2016; 32:265-272. [PMID: 28206858 DOI: 10.2987/16-6579.1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
This study was performed to establish the genetic variability of Aedes albopictus within Subang Jaya, Selangor, Malaysia, by using the nicotinamide adenine dinucleotide dehydrogenase 5 subunit (ND5) mitochondrial DNA (mtDNA) marker. A total of 90 samples were collected from 9 localities within an area of the Subang Jaya Municipality. Genetic variability was determined through the amplification and sequencing of a fragment of the ND5 gene. Eight distinct mtDNA haplotypes were identified. The evolutionary relationship of the local haplotypes alongside 28 reference strains was used to construct a phylogram, the analysis of which revealed low genetic differentiation in terms of both nucleotide and haplotype diversity. Bayesian method was used to infer the phylogenetic tree, revealing a unique relationship between local isolates. The study corroborates the reliability of ND5 to identify distinct lineages for polymorphism-based studies and supplements the existing body of knowledge regarding its genetic diversity. This in turn could potentially aid existing vector control strategies to help mitigate the risk and spread of the dengue virus.
Collapse
|
25
|
Rahim J, Ahmad AH, Kassim NFA, Ahmad H, Ishak IH, Rus AC, Maimusa HA. Revised Discriminating Lethal Doses For Resistance Monitoring Program on Aedes albopictus Against Temephos and Malathion in Penang Island, Malaysia. JOURNAL OF THE AMERICAN MOSQUITO CONTROL ASSOCIATION 2016; 32:210-216. [PMID: 27802400 DOI: 10.2987/16-6556.1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Dengue vector control still heavily relies on the use of chemical insecticides, and the widespread use of insecticides has led to resistance in mosquitoes. The diagnostic dose is a key part of resistance monitoring. The present study corroborates the discriminating lethal doses of temephos and malathion based on dose-response of known susceptible strain of Aedes albopictus following the World Health Organization (WHO) diagnostic test procedure. Late 3rd and early 4th instars were tested with a range of larvicides to determine the lethal concentrations (LC50 and LC99) values. A slightly higher diagnostic dose of 0.020 mg/liter as compared with the WHO-established value of 0.012 mg/liter was observed for temephos. Meanwhile, a malathion diagnostic dose of 0.200 mg/liter is also reported here since there are no such reported values by WHO. Doubling the LC99 values of susceptible strains, 3 of the 5 wild-collected populations showed resistance to temephos and 2 showed incipient resistance; all 5 populations showed incipient resistance to malathion. The revised and established lethal diagnostic dose findings from the current work are crucial to elaborate on the variation in susceptibility of Ae. albopictus in future resistance monitoring programs in Malaysia.
Collapse
|
26
|
Chen B, Yang J, Luo L, Yang Z, Liu Q. Who Is Vulnerable to Dengue Fever? A Community Survey of the 2014 Outbreak in Guangzhou, China. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2016; 13:ijerph13070712. [PMID: 27428986 PMCID: PMC4962253 DOI: 10.3390/ijerph13070712] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/11/2016] [Revised: 07/05/2016] [Accepted: 07/07/2016] [Indexed: 02/03/2023]
Abstract
Unprecedented dengue fever (DF) outbreaks impel China to develop useful disease control strategies. Integrated vector management (IVM) focuses on identifying vulnerable populations and interrupting human–vector contact; however, vulnerable populations have not been clearly identified in China. We conducted a case-control study during the initial stage of the 2014 DF outbreak in Guangzhou, China to assess risk factors for DF infection. Cases were randomly sampled from the National Notifiable Infectious Disease Reporting Information System (NNIDRIS). Controls were healthy individuals recruited from 17 DF infected communities through cluster sampling. A structured questionnaire on demographics, knowledge, practices, and living environment was administered to participants (165 cases; 492 controls). Logistic regression models identified characteristics of vulnerable populations. Awareness of dengue (OR = 0.08, 95% CI = 0.04–0.17), removing trash and stagnant water from around the residence (OR = 0.02, 95% CI = 0.00–0.17), and using mosquito repellent oils (OR = 0.36, 95% CI = 0.16–0.81) were protective factors. Living in an old flat or shed (OR = 2.38, 95% CI = 1.18–4.79) was a risk factor. Coils and bed nets were not protective due to incorrect knowledge of use. Using mosquito repellent oils and other protective measures can reduce vulnerability to DF infection.
Collapse
Affiliation(s)
- Bin Chen
- State Key Laboratory for Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China.
- China CDC Key Laboratory of Surveillance and Early-Warning on Infectious Disease, Chinese Center for Disease Control and Prevention, Beijing 102211, China.
- Xiamen Entry-Exit Inspection and Quarantine Bureau, Xiamen 361012, China.
| | - Jun Yang
- State Key Laboratory for Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China.
- China CDC Key Laboratory of Surveillance and Early-Warning on Infectious Disease, Chinese Center for Disease Control and Prevention, Beijing 102211, China.
| | - Lei Luo
- Guangzhou Center for Disease Control and Prevention, Guangzhou 510440, China.
| | - Zhicong Yang
- Guangzhou Center for Disease Control and Prevention, Guangzhou 510440, China.
| | - Qiyong Liu
- State Key Laboratory for Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China.
- China CDC Key Laboratory of Surveillance and Early-Warning on Infectious Disease, Chinese Center for Disease Control and Prevention, Beijing 102211, China.
| |
Collapse
|
27
|
Dengue and chikungunya: modelling the expansion of mosquito-borne viruses into naïve populations. Parasitology 2016; 143:860-873. [PMID: 27045211 DOI: 10.1017/s0031182016000421] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
With the recent global spread of a number of mosquito-borne viruses, there is an urgent need to understand the factors that contribute to the ability of viruses to expand into naïve populations. Using dengue and chikungunya viruses as case studies, we detail the necessary components of the expansion process: presence of the mosquito vector; introduction of the virus; and suitable conditions for local transmission. For each component we review the existing modelling approaches that have been used to understand recent emergence events or to assess the risk of future expansions. We identify gaps in our knowledge that are related to each of the distinct aspects of the human-mosquito transmission cycle: mosquito ecology; human-mosquito contact; mosquito-virus interactions; and human-virus interactions. Bridging these gaps poses challenges to both modellers and empiricists, but only through further integration of models and data will we improve our ability to better understand, and ultimately control, several infectious diseases that exert a significant burden on human health.
Collapse
|
28
|
Khan J, Khan I, Amin I. A Comprehensive Entomological, Serological and Molecular Study of 2013 Dengue Outbreak of Swat, Khyber Pakhtunkhwa, Pakistan. PLoS One 2016; 11:e0147416. [PMID: 26848847 PMCID: PMC4746065 DOI: 10.1371/journal.pone.0147416] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2015] [Accepted: 01/04/2016] [Indexed: 01/03/2023] Open
Abstract
BACKGROUND Aedes aegypti and Aedes albopictus play a fundamental role in transmission of dengue virus to humans. A single infected Aedes mosquito is capable to act as a reservoir/amplifier host for dengue virus and may cause epidemics via horizontal and vertical modes of dengue virus (DENV) transmission. The present and future dengue development can be clarified by understanding the elements which help the dissemination of dengue transmission. The current study deals with molecular surveillance of dengue in addition to ecological and social context of 2013 dengue epidemics in Swat, Pakistan. METHODS Herein, we reported dengue vectors surveillance in domestic and peridomistic containers in public and private places in 7 dengue epidemic-prone sites in District Swat, Pakistan from July to November 2013. Using the Flaviviruses genus-specific reverse transcriptase (RT) semi nested-PCR assay, we screened blood samples (N = 500) of dengue positive patients, 150 adult mosquito pools and 25 larval pools. RESULTS The 34 adult and 7 larval mosquito pools were found positive. The adult positive pools comprised 30 pools of Ae. aegypti and 4 pools of Ae. albopictus, while among the 7 larval pools, 5 pools of Ae. aegypti and 2 pools of Ae. albopictus were positive. The detected putative genomes of dengue virus were of DENV-2 (35% in 14 mosquito pools & 39% in serum) and DENV-3 (65% in 27 mosquito pools & 61% in serum). The higher vector density and dengue transmission rate was recorded in July and August (due to favorable conditions for vector growth). About 37% of Ae. aegpti and 34% Ae. albopictus mosquitoes were collected from stagnant water in drums, followed by drinking water tanks (23% & 26%), tires (20% & 18%) and discarded containers (10% & 6%). Among the surveyed areas, Saidu was heavily affected (26%) by dengue followed by Kanju (20% and Landikas (12%). The maximum infection was observed in the age group of <15 (40%) followed by 15-45 (35%) and >45 (25%) years and was more in males (55.3%) as compare to females (44.7%). The increase in vector mosquito density and the subsequent viral transmission was determined by a complex interplay of ecological, biological and social factors. CONCLUSION The suitable environmental conditions and discriminable role of Aedes through trans-ovarial transmission of DENV is indispensable in the recent geographic increase of dengue in Pakistan. Climate change affects the survival and dispersion of vectors as well as the transmission rates of dengue. Control of Aedes mosquitoes (vectors) and elimination of breeding sources must be emphasized and prioritized. Such actions may not only reduce the risk of dengue transmission during epidemics, but also minimize the chances of dengue viruses establishment in new (non endemic) areas of the region.
Collapse
Affiliation(s)
- Jehangir Khan
- Zoology Department, Abdul Wali Khan University Mardan (AWKUM), Bunir Campus, Khyber Pakhtunkhwa (KPK), Pakistan
- * E-mail:
| | - Inamullah Khan
- Nuclear Institute of Food and Agriculture (NIFA), G.T Road, Tarnab Peshawar, Pakistan
| | - Ibne Amin
- Zoology Department, Abdul Wali Khan University Mardan (AWKUM), Bunir Campus, Khyber Pakhtunkhwa (KPK), Pakistan
| |
Collapse
|
29
|
Marcela P, Hassan AA, Hamdan A, Dieng H, Kumara TK. Interspecific Cross-Mating Between Aedes aegypti and Aedes albopictus Laboratory Strains: Implication of Population Density on Mating Behaviors. JOURNAL OF THE AMERICAN MOSQUITO CONTROL ASSOCIATION 2015; 31:313-320. [PMID: 26675452 DOI: 10.2987/moco-31-04-313-320.1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Mating behavior between Aedes aegypti and Ae. albopictus, established colony strains were examined under laboratory conditions (30-cm(3) screened cages) for 5 consecutive days. The effect of selected male densities (30, 20, 10) and female density (20) on the number of swarming, mating pairs, eggs produced, and inseminated females were evaluated. Male densities significantly increased swarming behavior, mating pairs, and egg production of heterospecific females, but female insemination was reduced. Aedes aegypti males mate more readily with heterospecific females than do Ae. albopictus males. The current study suggests that Ae. aegypti males were not species-specific in mating, and if released into the field as practiced in genetically modified mosquito techniques, they may mate with both Ae. aegypti and Ae. albopictus females, hence reducing populations of both species by producing infertile eggs.
Collapse
Affiliation(s)
- P Marcela
- 1 School of Biological Sciences, Universiti Sains Malaysia, 11800 Penang, Malaysia
| | - A Abu Hassan
- 1 School of Biological Sciences, Universiti Sains Malaysia, 11800 Penang, Malaysia
| | - A Hamdan
- 1 School of Biological Sciences, Universiti Sains Malaysia, 11800 Penang, Malaysia
| | - H Dieng
- 2 Institute of Biodiversity and Environmental Conservation, Universiti Malaysia Sarawak, 94300 Kota Samarahan, Sarawak, Malaysia
| | - T K Kumara
- 3 Faculty of Agro Based Industry, Universiti Malaysia Kelantan, 17600 Jeli, Kelantan, Malaysia
| |
Collapse
|
30
|
Ismail NA, Dom NC, Ismail R, Ahmad AH, Zaki A, Camalxaman SN. Mitochondrial Cytochrome Oxidase I Gene Sequence Analysis of Aedes Albopictus in Malaysia. JOURNAL OF THE AMERICAN MOSQUITO CONTROL ASSOCIATION 2015; 31:305-312. [PMID: 26675451 DOI: 10.2987/moco-31-04-305-312.1] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
A study was conducted to establish polymorphic variation of the mitochondrial DNA encoding the cytochrome oxidase subunit 1 (CO1) gene in Aedes albopictus isolated from 2 hot spot dengue-infested areas in the Subang Jaya District, Malaysia. A phylogenetic analysis was performed with the use of sequences obtained from USJ6 and Taman Subang Mas (TSM). Comparison of the local CO1 sequences with a laboratory strain (USM), alongside reference strains derived from the GenBank database revealed low genetic variation in terms of nucleotide differences and haplotype diversity. Four methods were used to construct a phylogenetic tree and illustrate the genetic relationship of the 37 Ae. albopictus populations based on the CO1 sequences, namely neighbor-joining (NJ), maximum parsimony (MP), maximum likelihood (ML), and Bayesian method, which revealed a distinct relationship between isolates from USJ6 and TSM. Our findings provide new information regarding the genetic diversity among morphologically similar Ae. albopictus, which has not been reported to date.
Collapse
Affiliation(s)
- Nurul-Ain Ismail
- 1 Faculty of Health Sciences, Universiti Teknologi MARA, 42300 Puncak Alam, Selangor, Malaysia
| | - Nazri Che Dom
- 1 Faculty of Health Sciences, Universiti Teknologi MARA, 42300 Puncak Alam, Selangor, Malaysia
| | - Rodziah Ismail
- 1 Faculty of Health Sciences, Universiti Teknologi MARA, 42300 Puncak Alam, Selangor, Malaysia
| | - Abu Hassan Ahmad
- 2 School of Biological Sciences, Universiti Sains Malaysia, 11800 Pulau Pinang, Malaysia
| | - Afiq Zaki
- 1 Faculty of Health Sciences, Universiti Teknologi MARA, 42300 Puncak Alam, Selangor, Malaysia
| | - Siti Nazrina Camalxaman
- 1 Faculty of Health Sciences, Universiti Teknologi MARA, 42300 Puncak Alam, Selangor, Malaysia
| |
Collapse
|
31
|
Assessing dengue outbreak areas using vector surveillance in north east district, Penang Island, Malaysia. ASIAN PACIFIC JOURNAL OF TROPICAL DISEASE 2015. [DOI: 10.1016/s2222-1808(15)60947-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
|
32
|
Zuharah WF, Fadzly N, Yusof NA, Dieng H. Risky behaviors: effects of Toxorhynchites splendens (Diptera: Culicidae) predator on the behavior of three mosquito species. JOURNAL OF INSECT SCIENCE (ONLINE) 2015; 15:iev115. [PMID: 26386041 PMCID: PMC4626665 DOI: 10.1093/jisesa/iev115] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2015] [Accepted: 08/30/2015] [Indexed: 05/25/2023]
Abstract
Viable biocontrol agents for mosquito control are quite rare, therefore improving the efficacy of existing biological agents is an important study. We need to have a better understanding of the predation-risk behavioral responses toward prey. This research examined prey choices by Toxorhynchites splendens by monitoring the behavioral responses of Aedes aegypti, Aedes albopictus, and Anopheles sinensis larvae when exposed to the predator. The results show that Tx. splendens prefers to consume Ae. aegypti larvae. The larvae exhibited different behavioral responses when Tx. splendens was present which suggest vulnerability in the presence of predators. "Thrashing" and "browsing" activities were greater in Ae. aegypti larvae. Such active and risky movements could cause vulnerability for the Ae. aegypti larvae due to increasing of water disturbance. In contrast, Ae. albopictus and An. sinensis larvae exhibited passive, low-risk behaviors, spending most of the time on the "wall" position near the edges of the container. We postulated that Ae. aegypti has less ability to perceive cues from predation and could not successfully alter its behavior to reduce risk of predation risk compared with Ae. albopictus and An. sinensis. Our results suggest that Tx. splendens is a suitable biocontrol agent in controlling dengue hemorrhagic vector, Ae. aegypti.
Collapse
Affiliation(s)
- Wan Fatma Zuharah
- Medical Entomology Laboratory, School of Biological Sciences. Universiti Sains Malaysia, 11800 USM, Penang, Malaysia Vector Control Research Unit, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia
| | - Nik Fadzly
- Medical Entomology Laboratory, School of Biological Sciences. Universiti Sains Malaysia, 11800 USM, Penang, Malaysia Centre of Marine and Coastal Studies (CEMACS), Universiti Sains Malaysia, Penang 11800, Malaysia
| | - Nur Aishah Yusof
- Medical Entomology Laboratory, School of Biological Sciences. Universiti Sains Malaysia, 11800 USM, Penang, Malaysia
| | - Hamady Dieng
- Medical Entomology Laboratory, School of Biological Sciences. Universiti Sains Malaysia, 11800 USM, Penang, Malaysia Institute of Biodiversity and Environmental Conservation (IBEC), Universiti Malaysia Sarawak, Sarawak, Malaysia
| |
Collapse
|
33
|
Practices of Dengue Fever Prevention and the Associated Factors among the Orang Asli in Peninsular Malaysia. PLoS Negl Trop Dis 2015; 9:e0003954. [PMID: 26267905 PMCID: PMC4534093 DOI: 10.1371/journal.pntd.0003954] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2015] [Accepted: 07/06/2015] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Dengue is prevalent among Malaysia's indigenous peoples, known as the Orang Asli, and it poses a serious health threat to them. The study aims to look at the socio-demographic factors, health beliefs, and knowledge about dengue and its association to dengue prevention practices among Orang Asli communities in Peninsular Malaysia. METHODS A cross-sectional survey was conducted in 16 randomly selected Orang Asli villages from eight states in Peninsular Malaysia from April 2012 until February 2013. RESULTS A total of 560 Orang Asli were interviewed and 505 completed the survey. Slightly above half of the participants (n = 280, 55.4%) had a total dengue prevention score of 51-100 (of a possible score of 0-100). Multivariate analysis findings showed dengue knowledge, perceived barriers to perform dengue prevention, fogging frequency, and perceived susceptibility to dengue fever as significant factors associated to dengue prevention practices. Participants with a lower dengue knowledge score (score 0-18) were less likely (OR = 0.63, 95%CI = 0.44-0.92 vs. score 19-36, P = 0.015) to practice dengue prevention. Participants with low perceived barriers to prevent dengue (score of 1-5) were more likely (OR = 2.06, 95%CI = 1.21-3.53, vs. score of 6-10, P = 0.008) to practice dengue prevention. Villages that were not fogged (OR = 0.49, 95%CI = 0.24-0.99, P = 0.045) or rarely fogged (OR = 0.40, 95%CI = 0.22-0.75, P = 0.004) had lower dengue prevention practices than villages that were fogged often. Participants with low perceived susceptibility of acquiring dengue (score of 1-5) were less likely (OR = 0.54, 95%CI = 0.33-0.89 vs. score of 6-10, P = 0.018) to practice dengue prevention measures. CONCLUSION Findings imply that educational and health programmes should focus on enhancing dengue knowledge and perceived susceptibility of acquiring dengue and reducing perceived barriers to performing dengue prevention practices among the Orang Asli. More outreach on mosquito control campaigns should be carried out especially in villages where mosquito fogging is frequent.
Collapse
|
34
|
Joanne S, Vythilingam I, Yugavathy N, Leong CS, Wong ML, AbuBakar S. Distribution and dynamics of Wolbachia infection in Malaysian Aedes albopictus. Acta Trop 2015; 148:38-45. [PMID: 25899523 DOI: 10.1016/j.actatropica.2015.04.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2014] [Revised: 04/05/2015] [Accepted: 04/09/2015] [Indexed: 01/24/2023]
Abstract
Wolbachia are maternally transmitted bacteria found in most arthropods and nematodes, but little is known about their distribution and reproductive dynamics in the Malaysian dengue vector Aedes albopictus. In this study, polymerase chain reaction (PCR) was used to determine the presence of Wolbachia from field collected Ae. albopictus from various parts of the country using wsp specific primers. Ae. albopictus had Wolbachia infection ranging from 60 to 100%. No sequence diversity of wsp gene was found within all wAlbA and wAlbB sequences. Our findings suggest that Wolbachia infection amongst the Malaysian Ae. albopictus were not homogenously distributed in all districts in Malaysia. The presence of Wolbachia in different organs of Ae. albopictus was also determined. Wolbachia were only found in the ovaries and midguts of the mosquitoes, while absent in the salivary glands. The effects of Wolbachia on Ae. albopictus fecundity, longevity and egg viability were studied using infected and uninfected colonies. The removal of Wolbachia from Ae. albopictus resulted in reduced fecundity, longevity and egg viability, thus. Wolbachia seem to play a vital role in Ae. albopictus reproductive system.
Collapse
|
35
|
Mogi M, Armbruster P, Tuno N, Campos R, Eritja R. Simple Indices Provide Insight to Climate Attributes Delineating the Geographic Range of Aedes albopictus (Diptera: Culicidae) Prior to Worldwide Invasion. JOURNAL OF MEDICAL ENTOMOLOGY 2015; 52:647-657. [PMID: 26335471 DOI: 10.1093/jme/tjv038] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2014] [Accepted: 03/19/2015] [Indexed: 06/05/2023]
Abstract
Aedes albopictus (Skuse) has expanded its distribution worldwide during the past decades. Despite attempts to explain and predict its geographic occurrence, analyses of the distribution of Ae. albopictus in the context of broad climatic regions (biomes) has not been performed. We analyzed climate conditions at its distribution sites in the range before the worldwide invasions (from the easternmost Hawaii through westernmost Madagascar) by using thermal and aridity-humidity indices descriptive of major biomes. A significant advantage of this approach is that it uses simple indices clearly related to the population dynamics of Ae. albopictus. Although Ae. albopictus has been regarded as a forest species preferring humid climate, in areas with significant human habitation, the distribution sites extended from the perhumid, rain forest zone to the semiarid, steppe zone. This pattern was common from the tropics through the temperate zone. Across the distribution range, there was no seasonal discordance between temperature and precipitation; at sites where winter prevents Ae. albopictus reproduction (monthly means<10°C), precipitation was concentrated in warm months (>10°C) under the Asian summer monsoon. Absence of the species in northern and eastern coastal Australia and eastern coastal Africa was not attributable solely to climate conditions. However, Asia west of the summer monsoon range was climatically unsuitable because of low precipitation throughout the year or in warm months favorable to reproduction (concentration of precipitation in winter). We hypothesized that Ae. albopictus originated in continental Asia under the monsoon climate with distinct dry seasons and hot, wet summer, enabling rapid population growth.
Collapse
Affiliation(s)
- Motoyoshi Mogi
- Division of Parasitology, Department of Pathology and Biodefense, Faculty of Medicine, Saga University, Nabeshima 5-1-1, Saga, 849-8501, Japan (retired).
| | - Peter Armbruster
- Department of Biology, Georgetown University, 37th and O sts. NW, Washington, DC 20057
| | - Nobuko Tuno
- Laboratory of Ecology, Graduate School of Natural Science and Technology, Kanazawa University, Kanazawa, 920-1192, Japan
| | - Raúl Campos
- Instituto de Limnología Dr. Raúl A. Ringuelet, Universidad Nacional de La Plata - CONICET, CCT La Plata, Boulevard 120 y 62 - Casilla de Correo N° 712. 1900, La Plata, Buenos Aires, Argentina
| | - Roger Eritja
- Consell Comarcal del Baix Llobregat, Parc Torreblanca, 08980 Sant Feliu de Llobregat, Spain
| |
Collapse
|
36
|
Dieng H, Hassan RB, Hassan AA, Ghani IA, Abang FB, Satho T, Miake F, Ahmad H, Fukumitsu Y, Hashim NA, Zuharah WF, Kassim NFA, Majid AHA, Selvarajoo R, Nolasco-Hipolito C, Ajibola OO, Tuen AA. Occurrence of a mosquito vector in bird houses: Developmental consequences and potential epidemiological implications. Acta Trop 2015; 145:68-78. [PMID: 25617636 DOI: 10.1016/j.actatropica.2015.01.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2014] [Revised: 12/29/2014] [Accepted: 01/07/2015] [Indexed: 11/25/2022]
Abstract
Even with continuous vector control, dengue is still a growing threat to public health in Southeast Asia. Main causes comprise difficulties in identifying productive breeding sites and inappropriate targeted chemical interventions. In this region, rural families keep live birds in backyards and dengue mosquitoes have been reported in containers in the cages. To focus on this particular breeding site, we examined the capacity of bird fecal matter (BFM) from the spotted dove, to support Aedes albopictus larval growth. The impact of BFM larval uptake on some adult fitness traits influencing vectorial capacity was also investigated. In serial bioassays involving a high and low larval density (HD and LD), BFM and larval standard food (LSF) affected differently larval development. At HD, development was longer in the BFM environment. There were no appreciable mortality differences between the two treatments, which resulted in similar pupation and adult emergence successes. BFM treatment produced a better gender balance. There were comparable levels of blood uptake and egg production in BFM and LSF females at LD; that was not the case for the HD one, which resulted in bigger adults. BFM and LSF females displayed equivalent lifespans; in males, this parameter was shorter in those derived from the BFM/LD treatment. Taken together these results suggest that bird defecations successfully support the development of Ae. albopictus. Due to their cryptic aspects, containers used to supply water to encaged birds may not have been targeted by chemical interventions.
Collapse
|
37
|
Aziz AT, Dieng H, Ahmad AH, Mahyoub JA, Turkistani AM, Mesed H, Koshike S, Satho T, Salmah MC, Ahmad H, Zuharah WF, Ramli AS, Miake F. Household survey of container-breeding mosquitoes and climatic factors influencing the prevalence of Aedes aegypti (Diptera: Culicidae) in Makkah City, Saudi Arabia. Asian Pac J Trop Biomed 2015; 2:849-57. [PMID: 23569860 DOI: 10.1016/s2221-1691(12)60242-1] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2012] [Revised: 08/23/2012] [Accepted: 11/28/2012] [Indexed: 11/24/2022] Open
Abstract
OBJECTIVE To investigate the prevalence of container breeding mosquitoes with emphasis on the seasonality and larval habitats of Aedes aegypti (Ae. aegypti) in Makkah City, adjoining an environmental monitoring and dengue incidence. METHODS Monthly visits were performed between April 2008 and March 2009 to randomly selected houses. During each visit, mosquito larvae were collected from indoors and outdoors containers by either dipping or pipetting. Mosquitoes were morphologically identified. Data on temperature, relative humidity, rain/precipitations during the survey period was retrieved from governmental sources and analyzed. RESULTS The city was warmer in dry season (DS) than wet season (WS). No rain occurred at all during DS and even precipitations did fall, wetting events were much greater during WS. Larval survey revealed the co-breeding of Aedes, Culex and Anopheles in a variety of artificial containers in and around homes. 32 109 larvae representing 1st , 2nd, 3rd, and 4th stages were collected from 22 618 container habitats. Culicines was far the commonest and Aedes genus was as numerous as the Culex population. Ae. aegypti larval abundance exhibited marked temporal variations, overall, being usually more abundant during WS. Ten types of artificial containers were found with developing larvae. 70% of these habitats were located indoors. 71.42% of indoor containers were permanent and 28.58% was semi-permanent during WS. Cement tanks was the only container type permanent during DS. Ae. aegypti larval indices (CI, HI, BI) recorded were greater during WS. CONCLUSIONS Taken together, these results indicate a high risk of dengue transmission in the holy city.
Collapse
Affiliation(s)
- Al Thabiany Aziz
- Medical Entomology Laboratory, School of Biological Sciences, Universiti Sains Malaysia, 11800 Minden, Penang, Malaysia
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
38
|
Dieng H, Saifur RGM, Ahmad AH, Salmah MRC, Aziz AT, Satho T, Miake F, Jaal Z, Abubakar S, Morales RE. Unusual developing sites of dengue vectors and potential epidemiological implications. Asian Pac J Trop Biomed 2015; 2:228-32. [PMID: 23569903 DOI: 10.1016/s2221-1691(12)60047-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2011] [Revised: 09/01/2011] [Accepted: 09/24/2011] [Indexed: 11/29/2022] Open
Abstract
OBJECTIVE To identify the unusual breeding sites of two dengue vectors, i.e. Aedes albopictus (Ae. albopictus) and Aedes aegypti (Ae. aegypti). METHODS During the second half of 2010, we performed an occasional survey in rural (Teluk Tempoyak) and urban (Gelugor) areas of Penang Island, Malaysia, to identify cryptic breeding sites. RESULTS In the rural area, we found heterogeneous immature stages of Ae. albopictus in the water bowl of an encaged bird. We also observed Ae. aegypti eggs deposited in the flush tank of a toilet in the urban area. CONCLUSIONS It can be concluded that both breeding patterns can increase contact with hosts (humans and birds) and presumably population densities of Ae. albopictus and Ae. aegypti, thereby potentially boosting the risks for spread and transmission of arboviral diseases.
Collapse
Affiliation(s)
- Hamady Dieng
- School of Biological Sciences, Universiti Sains Malaysia, Penang, Malaysia
| | | | | | | | | | | | | | | | | | | |
Collapse
|
39
|
Aida HN, Dieng H, Ahmad AH, Satho T, Nurita AT, Salmah MRC, Miake F, Norasmah B. The biology and demographic parameters of Aedes albopictus in northern peninsular Malaysia. Asian Pac J Trop Biomed 2015; 1:472-7. [PMID: 23569816 DOI: 10.1016/s2221-1691(11)60103-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2011] [Revised: 04/27/2011] [Accepted: 05/11/2011] [Indexed: 10/28/2022] Open
Abstract
OBJECTIVE To generate life table characteristics for the dengue vector Aedes albopictus (A. albopictus) under uncontrolled conditions, incorporating both the aquatic and the adult stages. METHODS Ten females derived from wild pupae were allowed to fully blood-feed on restrained mice. 774 eggs were hatched in seasoned water. F1 larvae were followed for development until their F2 counterparts emerged as adults. Some population parameters were monitored (F1) or estimated (F2). RESULTS A. albopictus exhibited increased fecundity and egg hatch success. Immature development was quick. Immature survival was high, with lowest rate in the pupal stage. Adult emergence was about 81% and sex ratio was close to 1:1. Generational mortality (K) was about 28%. A high proportion of females completed a reproductive cycle and the obtained parity rate was predicted to lead to higher fecundity in the next generation. CONCLUSIONS It can be concluded that natural A. albopictus populations in Penang seem largely determined by quick development in combination with low immature loss and increased oviposition.
Collapse
Affiliation(s)
- H Nur Aida
- Medical Entomology Laboratory, School of Biological Sciences, Universiti Sains Malaysia, 11800 Minden, Penang, Malaysia
| | | | | | | | | | | | | | | |
Collapse
|
40
|
Wong LP, AbuBakar S, Chinna K. Community knowledge, health beliefs, practices and experiences related to dengue fever and its association with IgG seropositivity. PLoS Negl Trop Dis 2014; 8:e2789. [PMID: 24853259 PMCID: PMC4031145 DOI: 10.1371/journal.pntd.0002789] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2012] [Accepted: 03/02/2014] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Demographic, economic and behavioural factors are central features underpinning the successful management and biological control of dengue. This study aimed to examine these factors and their association with the seroprevalence of this disease. METHODOLOGY We conducted a cross-sectional telephone survey of households in a 3 km radius of the schools where we had conducted serological tests on the student population in a previous study. Households were surveyed about their socio-demographics, knowledge, practices, and Health Belief Model (HBM) constructs. The results were then associated with the prevalence rate of dengue in the community, as marked by IgG seropositivity of the students who attended school there. RESULTS A total of 1,400 complete responses were obtained. The community's IgG seropositivity was significantly positively associated with high household monthly income, high-rise residential building type, high surrounding vegetation density, rural locality, high perceived severity and susceptibility, perceived barriers to prevention, knowing that a neighbour has dengue, frequent fogging and a higher level of knowledge about dengue. In the multivariate analyses, three major correlates of the presence of IgG seropositivity in the community: (1) high-rise residential apartment house type or condominium buildings; (2) the main construct of the HBM, perceived severity and susceptibility; and (3) the additional constructs of the HBM, lack of preventive measures from the community level and having a neighbour with dengue as a cue to action. Weak correlations were found between self-practices to prevent dengue and the level of dengue seropositivity in the community, and between HBM constructs and knowledge (r = 0.09). CONCLUSIONS The residential environment factor and the constructs of the HBM are useful and important elements in developing interventions to prevent and control dengue. The study also sheds light on the importance of the need for approaches that ensure the translation of knowledge into practice.
Collapse
Affiliation(s)
- Li Ping Wong
- Department of Social and Preventive Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
- Julius Centre University of Malaya (JCUM), University of Malaya, Kuala Lumpur, Malaysia
- * E-mail:
| | - Sazaly AbuBakar
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
- Tropical Infectious Diseases Research and Educational Centre (TIDREC), University of Malaya, Kuala Lumpur, Malaysia
| | - Karuthan Chinna
- Department of Social and Preventive Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
- Julius Centre University of Malaya (JCUM), University of Malaya, Kuala Lumpur, Malaysia
| |
Collapse
|
41
|
Petrić D, Bellini R, Scholte EJ, Rakotoarivony LM, Schaffner F. Monitoring population and environmental parameters of invasive mosquito species in Europe. Parasit Vectors 2014; 7:187. [PMID: 24739334 PMCID: PMC4005621 DOI: 10.1186/1756-3305-7-187] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2013] [Accepted: 04/11/2014] [Indexed: 12/02/2022] Open
Abstract
To enable a better understanding of the overwhelming alterations in the invasive mosquito species (IMS), methodical insight into the population and environmental factors that govern the IMS and pathogen adaptations are essential. There are numerous ways of estimating mosquito populations, and usually these describe developmental and life-history parameters. The key population parameters that should be considered during the surveillance of invasive mosquito species are: (1) population size and dynamics during the season, (2) longevity, (3) biting behaviour, and (4) dispersal capacity. Knowledge of these parameters coupled with vector competence may help to determine the vectorial capacity of IMS and basic disease reproduction number (R0) to support mosquito borne disease (MBD) risk assessment. Similarly, environmental factors include availability and type of larval breeding containers, climate change, environmental change, human population density, increased human travel and goods transport, changes in living, agricultural and farming habits (e.g. land use), and reduction of resources in the life cycle of mosquitoes by interventions (e.g. source reduction of aquatic habitats). Human population distributions, urbanisation, and human population movement are the key behavioural factors in most IMS-transmitted diseases. Anthropogenic issues are related to the global spread of MBD such as the introduction, reintroduction, circulation of IMS and increased exposure to humans from infected mosquito bites. This review addresses the population and environmental factors underlying the growing changes in IMS populations in Europe and confers the parameters selected by criteria of their applicability. In addition, overview of the commonly used and newly developed tools for their monitoring is provided.
Collapse
Affiliation(s)
- Dušan Petrić
- University of Novi Sad, Faculty of Agriculture, Laboratory for Medical Entomology, Trg D. Obradovića 8, 21000 Novi Sad, Serbia
| | - Romeo Bellini
- Centro Agricoltura Ambiente "G. Nicoli", Via Argini Nord 3351, 40014 Crevalcore, Italy
| | - Ernst-Jan Scholte
- National Centre for Monitoring of Vectors, Dutch Food and Consumer Product Safety Authority (NVWA), Geertjesweg 15, P.O. Box 9102, 6700, HC, Wageningen, The Netherlands
| | | | | |
Collapse
|
42
|
Waldock J, Chandra NL, Lelieveld J, Proestos Y, Michael E, Christophides G, Parham PE. The role of environmental variables on Aedes albopictus biology and chikungunya epidemiology. Pathog Glob Health 2014; 107:224-41. [PMID: 23916332 DOI: 10.1179/2047773213y.0000000100] [Citation(s) in RCA: 117] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Aedes albopictus is a vector of dengue and chikungunya viruses in the field, along with around 24 additional arboviruses under laboratory conditions. As an invasive mosquito species, Ae. albopictus has been expanding in geographical range over the past 20 years, although the poleward extent of mosquito populations is limited by winter temperatures. Nonetheless, population densities depend on environmental conditions and since global climate change projections indicate increasing temperatures and altered patterns of rainfall, geographic distributions of previously tropical mosquito species may change. Although mathematical models can provide explanatory insight into observed patterns of disease prevalence in terms of epidemiological and entomological processes, understanding how environmental variables affect transmission is possible only with reliable model parameterisation, which, in turn, is obtained only through a thorough understanding of the relationship between mosquito biology and environmental variables. Thus, in order to assess the impact of climate change on mosquito population distribution and regions threatened by vector-borne disease, a detailed understanding (through a synthesis of current knowledge) of the relationship between climate, mosquito biology, and disease transmission is required, but this process has not yet been undertaken for Ae. albopictus. In this review, the impact of temperature, rainfall, and relative humidity on Ae. albopictus development and survival are considered. Existing Ae. albopictus populations across Europe are mapped with current climatic conditions, considering whether estimates of climatic cutoffs for Ae. albopictus are accurate, and suggesting that environmental thresholds must be calibrated according to the scale and resolution of climate model outputs and mosquito presence data.
Collapse
|
43
|
Indirect effects of cigarette butt waste on the dengue vector Aedes aegypti (Diptera: Culicidae). Acta Trop 2014; 130:123-30. [PMID: 24239749 DOI: 10.1016/j.actatropica.2013.11.001] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2013] [Revised: 11/04/2013] [Accepted: 11/05/2013] [Indexed: 11/23/2022]
Abstract
Despite major insecticide-based vector control programs, dengue continues to be a major threat to public health in urban areas. The reasons for this failure include the emergence of insecticide resistance and the narrowing of the spectrum of efficient products. Cigarette butts (CBs), the most commonly discarded piece of waste, also represent a major health hazard to human and animal life. CBs are impregnated with thousands of chemical compounds, many of which are highly toxic and none of which has history of resistance in mosquitoes. This study was performed to examine whether exposure to CB alters various biological parameters of parents and their progeny. We examined whether the mosquito changes its ovipositional behaviors, egg hatching, reproductive capacity, longevity and fecundity in response to CB exposure at three different concentrations. Females tended to prefer microcosms containing CBs for egg deposition than those with water only. There were equivalent rates of eclosion success among larvae from eggs that matured in CB and water environments. We also observed decreased life span among adults that survived CB exposure. Extracts of CB waste have detrimental effects on the fecundity and longevity of its offspring, while being attractive to its gravid females. These results altogether indicate that CB waste indirectly affect key adult life traits of Aedes aegypti and could conceivably be developed as a novel dengue vector control strategy, referring to previously documented direct toxicity on the larval stage. But this will require further research on CB waste effects on non-target organisms including humans.
Collapse
|
44
|
Novel Genetic and Molecular Tools for the Investigation and Control of Dengue Virus Transmission by Mosquitoes. CURRENT TROPICAL MEDICINE REPORTS 2014; 1:21-31. [PMID: 24693489 DOI: 10.1007/s40475-013-0007-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Aedes aegypti is the principal vector of dengue virus (DENV) throughout the tropical world. This anthropophilic mosquito species needs to be persistently infected with DENV before it can transmit the virus through its saliva to a new vertebrate host. In the mosquito, DENV is confronted with several innate immune pathways, among which RNA interference is considered the most important. The Ae. aegypti genome project opened the doors for advanced molecular studies on pathogen-vector interactions including genetic manipulation of the vector for basic research and vector control purposes. Thus, Ae. aegypti has become the primary model for studying vector competence for arboviruses at the molecular level. Here, we present recent findings regarding DENV-mosquito interactions, emphasizing how innate immune responses modulate DENV infections in Ae. aegypti. We also describe the latest advancements in genetic manipulation of Ae. aegypti and discuss how this technology can be used to investigate vector transmission of DENV at the molecular level and to control transmission of the virus in the field.
Collapse
|
45
|
Cheong YL, Burkart K, Leitão PJ, Lakes T. Assessing weather effects on dengue disease in Malaysia. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2013; 10:6319-34. [PMID: 24287855 PMCID: PMC3881116 DOI: 10.3390/ijerph10126319] [Citation(s) in RCA: 100] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/23/2013] [Revised: 11/04/2013] [Accepted: 11/08/2013] [Indexed: 11/23/2022]
Abstract
The number of dengue cases has been increasing on a global level in recent years, and particularly so in Malaysia, yet little is known about the effects of weather for identifying the short-term risk of dengue for the population. The aim of this paper is to estimate the weather effects on dengue disease accounting for non-linear temporal effects in Selangor, Kuala Lumpur and Putrajaya, Malaysia, from 2008 to 2010. We selected the weather parameters with a Poisson generalized additive model, and then assessed the effects of minimum temperature, bi-weekly accumulated rainfall and wind speed on dengue cases using a distributed non-linear lag model while adjusting for trend, day-of-week and week of the year. We found that the relative risk of dengue cases is positively associated with increased minimum temperature at a cumulative percentage change of 11.92% (95% CI: 4.41-32.19), from 25.4 °C to 26.5 °C, with the highest effect delayed by 51 days. Increasing bi-weekly accumulated rainfall had a positively strong effect on dengue cases at a cumulative percentage change of 21.45% (95% CI: 8.96, 51.37), from 215 mm to 302 mm, with the highest effect delayed by 26-28 days. The wind speed is negatively associated with dengue cases. The estimated lagged effects can be adapted in the dengue early warning system to assist in vector control and prevention plan.
Collapse
Affiliation(s)
- Yoon Ling Cheong
- Geoinformation Science Lab, Department of Geography, Humboldt-Universität zu Berlin, Unter den Linden 6, Berlin 10099, Germany; E-Mail:
- Medical Research Resource Centre, Institute for Medical Research, Jalan Pahang, Kuala Lumpur 50588, Malaysia
| | - Katrin Burkart
- Climatological Section, Department of Geography, Humboldt-Universität zu Berlin, Unter den Linden 6, Berlin 10099, Germany; E-Mail:
| | - Pedro J. Leitão
- Geomatics Lab, Department of Geography, Humboldt-Universität zu Berlin, Unter den Linden 6, Berlin 10099, Germany; E-Mail:
| | - Tobia Lakes
- Geoinformation Science Lab, Department of Geography, Humboldt-Universität zu Berlin, Unter den Linden 6, Berlin 10099, Germany; E-Mail:
| |
Collapse
|
46
|
Serpa LLN, Monteiro Marques GRA, de Lima AP, Voltolini JC, Arduino MDB, Barbosa GL, Andrade VR, de Lima VLC. Study of the distribution and abundance of the eggs of Aedes aegypti and Aedes albopictus according to the habitat and meteorological variables, municipality of São Sebastião, São Paulo State, Brazil. Parasit Vectors 2013; 6:321. [PMID: 24499530 PMCID: PMC3843558 DOI: 10.1186/1756-3305-6-321] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2013] [Accepted: 10/10/2013] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND This study focused on the distribution and abundance of the eggs of Aedes aegypti and Aedes albopictus. METHODS Eighty ovitraps were exposed for four days of each month in peri- and intradomiciliary environments of 40 urban residences on 20 street blocks that were drawn monthly in Sebastião, SP, between February 2011 and February 2012. The monthly distribution of positive ovitrap indices (POI) and mean egg counts per trap (MET) of Ae. aegypti and Ae. albopictus were analyzed using the Kruskal-Wallis test, followed by the Dwass-Steel-Critchlow-Fligner (DSCF) test. Spearman's rank correlation coefficient and simple linear regression were used to determine the association between the meteorological variables of temperature and rainfall and the number of ovitraps with eggs and the egg count. RESULTS The POI and MET of Ae. aegypti were higher in peridomiciliary premises. A positive correlation was found between the temperature and the number of ovitraps with eggs and the egg count of this species in domestic environments. There was no difference in the POI and MET of Ae. albopictus between the environments. A positive correlation was found between temperature and positive ovitraps of Ae. albopictus in peridomiciliary premises. The POI and MET of Ae. aegypti were higher than those of Ae. albopictus. CONCLUSIONS Peridomiciliary premises were the preferred environments for oviposition of Ae. aegypti. The use of ovitraps for surveillance and vector control is reiterated.
Collapse
Affiliation(s)
- Lígia Leandro Nunes Serpa
- Superintendência de Controle de Endemias, Praça Coronel Vitoriano, 23 Jardim Santa Clara, Centro, Taubaté, São Paulo CEP 12020-020, Brasil
| | | | - Ana Paula de Lima
- Superintendência de Controle de Endemias, Praça Coronel Vitoriano, 23 Jardim Santa Clara, Centro, Taubaté, São Paulo CEP 12020-020, Brasil
| | - Júlio Cesar Voltolini
- Universidade de Taubaté, Avenida Tiradentes, 500, Bom Conselho, Taubaté, São Paulo CEP 12030-180, Brasil
| | - Marylene de Brito Arduino
- Superintendência de Controle de Endemias, Praça Coronel Vitoriano, 23 Jardim Santa Clara, Centro, Taubaté, São Paulo CEP 12020-020, Brasil
| | - Gerson Laurindo Barbosa
- Superintendência de Controle de Endemias, Rua Paula Souza, 166, Luz, São Paulo, São Paulo CEP 01027-000, Brasil
| | - Valmir Roberto Andrade
- Superintendência de Controle de Endemias, Rua São Carlos, 546, Vila Industrial, Campinas, São Paulo CEP 13035-420, Brasil
| | - Virgília Luna Castor de Lima
- Superintendência de Controle de Endemias, Rua São Carlos, 546, Vila Industrial, Campinas, São Paulo CEP 13035-420, Brasil
| |
Collapse
|
47
|
Zhou JH, Zhang J, Sun DJ, Ma Q, Chen HT, Ma LN, Ding YZ, Liu YS. The distribution of synonymous codon choice in the translation initiation region of dengue virus. PLoS One 2013; 8:e77239. [PMID: 24204777 PMCID: PMC3808402 DOI: 10.1371/journal.pone.0077239] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2013] [Accepted: 08/30/2013] [Indexed: 11/18/2022] Open
Abstract
Dengue is the most common arthropod-borne viral (Arboviral) illness in humans. The genetic features concerning the codon usage of dengue virus (DENV) were analyzed by the relative synonymous codon usage, the effective number of codons and the codon adaptation index. The evolutionary distance between DENV and the natural hosts (Homo sapiens, Pan troglodytes, Aedes albopictus and Aedes aegypti) was estimated by a novel formula. Finally, the synonymous codon usage preference for the translation initiation region of this virus was also analyzed. The result indicates that the general trend of the 59 synonymous codon usage of the four genotypes of DENV are similar to each other, and this pattern has no link with the geographic distribution of the virus. The effect of codon usage pattern of Aedes albopictus and Aedes aegypti on the formation of codon usage of DENV is stronger than that of the two primates. Turning to the codon usage preference of the translation initiation region of this virus, some codons pairing to low tRNA copy numbers in the two primates have a stronger tendency to exist in the translation initiation region than those in the open reading frame of DENV. Although DENV, like other RNA viruses, has a high mutation to adapt its hosts, the regulatory features about the synonymous codon usage have been 'branded' on the translation initiation region of this virus in order to hijack the translational mechanisms of the hosts.
Collapse
Affiliation(s)
- Jian-hua Zhou
- State Key Laboratory of Veterinary Etiological Biology, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences. Lanzhou, Gansu, P.R. China
| | - Jie Zhang
- State Key Laboratory of Veterinary Etiological Biology, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences. Lanzhou, Gansu, P.R. China
| | - Dong-jie Sun
- State Key Laboratory of Veterinary Etiological Biology, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences. Lanzhou, Gansu, P.R. China
| | - Qi Ma
- State Key Laboratory of Veterinary Etiological Biology, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences. Lanzhou, Gansu, P.R. China
| | - Hao-tai Chen
- State Key Laboratory of Veterinary Etiological Biology, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences. Lanzhou, Gansu, P.R. China
| | - Li-na Ma
- State Key Laboratory of Veterinary Etiological Biology, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences. Lanzhou, Gansu, P.R. China
| | - Yao-zhong Ding
- State Key Laboratory of Veterinary Etiological Biology, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences. Lanzhou, Gansu, P.R. China
| | - Yong-sheng Liu
- State Key Laboratory of Veterinary Etiological Biology, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences. Lanzhou, Gansu, P.R. China
- * E-mail:
| |
Collapse
|
48
|
Survivorship of adult Aedes albopictus (Diptera: Culicidae) feeding on indoor ornamental plants with no inflorescence. Parasitol Res 2013; 112:2313-8. [DOI: 10.1007/s00436-013-3396-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2012] [Accepted: 03/11/2013] [Indexed: 10/27/2022]
|
49
|
Das B, Das M, Dwibedi B, Kar SK, Hazra RK. Molecular investigations of dengue virus during outbreaks in Orissa state, Eastern India from 2010 to 2011. INFECTION GENETICS AND EVOLUTION 2013; 16:401-10. [PMID: 23523598 DOI: 10.1016/j.meegid.2013.03.016] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2012] [Revised: 03/01/2013] [Accepted: 03/09/2013] [Indexed: 11/26/2022]
Abstract
Dengue is one of the most important arboviral diseases in India. Orissa state in Eastern India reported the first dengue outbreak in 2010, followed by extensive outbreaks in 2011, affecting large number of people. Detailed entomological, serological and phylogenetic investigations were performed in mosquitoes and patients serum collected from dengue virus (DENV) affected areas of Orissa. The combination of DENV specific IgM capture-ELISA and reverse-transcription PCR (RT-PCR) detected high DENV positivity in serum samples. DENV was detected in mosquitoes reared from field caught pupae by RT-PCR, which confirmed the vertical transmission of DENV that may have an important role in the recurrence of dengue outbreaks. Phylogenetic analyses revealed the circulation of Indian lineage of DENV-2 (genotype-IV) and DENV-3 (genotype-III) in vectors and patients serum in Orissa from 2010 to 2011, DENV-2 being the prevailing serotype. Selection analyses within the C-prM region showed that the emergence of DENV-2 and DENV-3 in Orissa was constrained by purifying selection which suggested the role of ecological factors like mosquito density and behavior in the recurrent outbreaks. Aedes albopictus was found to be the most abundant vector in the areas surveyed, followed by Aedes aegypti. Indoor breeding spots (earthen pots) were most abundant, with high pupal productivity (38.50) and contributed maximum Aedes species in the affected areas. The DENV infection rate estimated by maximum likelihood estimate (MLE) was high for indoor breeding Aedes (4.87; 95% CI: 1.82, 10.78) in comparison to outdoor breeding Aedes (1.55; 95% CI: 0.09, 7.55). The high MLE in Ae. albopictus (4.72; 95% CI: 1.94, 9.80) in comparison to Ae. aegypti (1.55; 95% CI: 0.09, 7.54) indicated that Ae. albopictus was the main DENV vector responsible for the outbreaks. The results indicated the circulation of two virulent serotypes of DENV in Orissa, mainly by Ae. albopictus with the implication for implementation of intradomecile vector control measures to prevent the spread of dengue.
Collapse
Affiliation(s)
- Biswadeep Das
- Regional Medical Research Center, Bhubaneswar, Orissa 751023, India
| | | | | | | | | |
Collapse
|
50
|
Saboia-Vahia L, Borges-Veloso A, Mesquita-Rodrigues C, Cuervo P, Dias-Lopes G, Britto C, Silva APDB, De Jesus JB. Trypsin-like serine peptidase profiles in the egg, larval, and pupal stages of Aedes albopictus. Parasit Vectors 2013; 6:50. [PMID: 23445661 PMCID: PMC3606343 DOI: 10.1186/1756-3305-6-50] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2012] [Accepted: 02/18/2013] [Indexed: 11/25/2022] Open
Abstract
BACKGROUND Aedes albopictus, a ubiquitous mosquito, is one of the main vectors of dengue and yellow fever, representing an important threat to public health worldwide. Peptidases play key roles in processes such as digestion, oogenesis, and metamorphosis of insects. However, most of the information on the proteolytic enzymes of mosquitoes is derived from insects in the adult stages and is often directed towards the understanding of blood digestion. The aim of this study was to investigate the expression of active peptidases from the preimaginal stages of Ae. albopictus. METHODS Ae. albopictus eggs, larvae, and pupae were analyzed using zymography with susbtrate-SDS-PAGE. The pH, temperature and peptidase inhibitor sensitivity was evaluated. In addition, the proteolytic activities of larval instars were assayed using the fluorogenic substrate Z-Phe-Arg-AMC. RESULTS The proteolytic profile of the larval stage was composed of 8 bands ranging from 17 to 130 kDa. These enzymes displayed activity in a broad range of pH values, from 5.5 to 10.0. The enzymatic profile of the eggs was similar to that of the larvae, although the proteolytic bands of the eggs showed lower intensities. The pupal stage showed a complex proteolytic pattern, with at least 6 bands with apparent molecular masses ranging from 30 to 150 kDa and optimal activity at pH 7.5. Peptidases from larval instars were active from 10°C to 60°C, with optimal activity at temperatures between 37°C and 50°C. The proteolytic profile of both the larval and pupal stages was inhibited by phenyl-methyl sulfonyl-fluoride (PMSF) and Nα-Tosyl L-lysine chloromethyl ketone hydrochloride (TLCK), indicating that the main peptidases expressed during these developmental stages are trypsin-like serine peptidases. CONCLUSION The preimaginal stages of Ae. albopictus exhibited a complex profile of trypsin-like serine peptidase activities. A comparative analysis of the active peptidase profiles revealed differential expression of trypsin-like isoforms among the preimaginal stages, suggesting that some of these enzymes are stage specific. Additionally, a comparison of the peptidase expression between larvae from eggs collected in the natural environment and larvae obtained from the eggs of female mosquitoes maintained in colonies for a long period of time demonstrated that the proteolytic profile is invariable under such conditions.
Collapse
Affiliation(s)
- Leonardo Saboia-Vahia
- Laboratório de Biologia Molecular e Doenças Endêmicas, Instituto Oswaldo Cruz, FIOCRUZ, Rio de Janeiro, Brazil
| | - André Borges-Veloso
- Laboratório de Biologia Molecular e Doenças Endêmicas, Instituto Oswaldo Cruz, FIOCRUZ, Rio de Janeiro, Brazil
| | - Camila Mesquita-Rodrigues
- Laboratório de Biologia Molecular e Doenças Endêmicas, Instituto Oswaldo Cruz, FIOCRUZ, Rio de Janeiro, Brazil
| | - Patricia Cuervo
- Laboratório de Pesquisa em Leishmaniose, Instituto Oswaldo Cruz, FIOCRUZ, Rio de Janeiro, Brazil
| | - Geovane Dias-Lopes
- Laboratório de Biologia Molecular e Doenças Endêmicas, Instituto Oswaldo Cruz, FIOCRUZ, Rio de Janeiro, Brazil
| | - Constança Britto
- Laboratório de Biologia Molecular e Doenças Endêmicas, Instituto Oswaldo Cruz, FIOCRUZ, Rio de Janeiro, Brazil
| | - Ana Paula de Barros Silva
- Laboratório de Biologia Molecular e Doenças Endêmicas, Instituto Oswaldo Cruz, FIOCRUZ, Rio de Janeiro, Brazil
| | - Jose B De Jesus
- Laboratório de Biologia Molecular e Doenças Endêmicas, Instituto Oswaldo Cruz, FIOCRUZ, Rio de Janeiro, Brazil
- Departamento de Engenharia de Biossistemas, Universidade Federal de São João Del Rey, Minas Gerais, Brazil
| |
Collapse
|