bims-mosdis Biomed News
on Mosquito distribution and disease
Issue of 2023‒06‒11
ten papers selected by
Richard Halfpenny, Staffordshire University
  1. Assessing vector competence of mosquitoes from northeastern France to West Nile virus and Usutu virus.
  2. FAUNA AND VIROLOGICAL INVESTIGATION OF MOSQUITOES IN URBAN PARKS IN SÃO PAULO, BRAZIL.
  3. Composition of Anopheles species and bionomic characteristics over the peak malaria transmission season in Bandarban, Bangladesh.
  4. COUNTY RECORDS FOR AEDES JAPONICUS IN GEORGIA.
  5. The Threat of Vector-Borne Diseases in Sierra Leone.
  6. Knowledge, Attitude and Practices Towards Dengue Fever Among Slum Dwellers: A Case Study in Dhaka City, Bangladesh.
  7. Mosquito bed net use and associated factors among pregnant women in Rwanda: a nationwide survey.
  8. Dengue in Myanmar: Spatiotemporal epidemiology, association with climate and short-term prediction.
  9. High-risk spatial clusters for Zika, dengue, and chikungunya in Rio de Janeiro, Brazil.
  10. Ecological drivers of sustained enzootic yellow fever virus transmission in Brazil, 2017-2021.
  1. PLoS Negl Trop Dis. 2023 Jun 05. 17(6): e0011144
    Assessing vector competence of mosquitoes from northeastern France to West Nile virus and Usutu virus.
    Jean-Philippe Martinet, Chloé Bohers, Marie Vazeille, Hubert Ferté, Laurence Mousson, Bruno Mathieu, Jérôme Depaquit, Anna-Bella Failloux.
      West Nile virus (WNV) and Usutu virus (USUV) are two arthropod-borne viruses that circulate in mainland France. Assessing vector competence has only been conducted so far with mosquitoes from southern France while an increasingly active circulation of WNV and USUV has been reported in the last years. The main vectors are mosquitoes of the Culex genus and the common mosquito Culex pipiens. Here, we measure the vector competence of five mosquito species (Aedes rusticus, Aedes albopictus, Anopheles plumbeus, Culex pipiens and Culiseta longiareolata) present in northeastern France. Field-collected populations were exposed to artificial infectious blood meal containing WNV or USUV and examined at different days post-infection. We show that (i) Cx. pipiens transmitted WNV and USUV, (ii) Ae. rusticus only WNV, and (iii) unexpectedly, Ae. albopictus transmitted both WNV and USUV. Less surprising, An. plumbeus was not competent for both viruses. Combined with data on distribution and population dynamics, these assessments of vector competence will help in developing a risk map and implementing appropriate prevention and control measures.
    DOI:  https://doi.org/10.1371/journal.pntd.0011144
  2. J Am Mosq Control Assoc. 2023 Jun 01.
    FAUNA AND VIROLOGICAL INVESTIGATION OF MOSQUITOES IN URBAN PARKS IN SÃO PAULO, BRAZIL.
    Marta R Heinisch, Antônio R Medeiros-Sousa, Pâmela S Andrade, Paulo R Urbinatti, Rosa M M S Almeida, Tamara N Lima-Camara.
      The mosquito fauna in urban parks in the city of São Paulo, Brazil, was investigated and compared for richness and diversity, and the abundance of each species was associated with climatic variables. Simultaneously, a virological investigation was performed to test the presence of Flavivirus and Alphavirus. Aspirations of adult mosquitoes were conducted in 3 urban parks for 3 consecutive weeks of each season between October 2018 and January 2020. A total of 2,388 mosquitoes were identified, with Culex quinquefasciatus, Cx. nigripalpus, and Aedes aegypti being the most abundant species. Mosquito assemblages showed similar richness and diversity, showing variability in individual results. Temperatures and Ae. aegypti abundance correlated significantly in one of the parks investigated herein. Urban parks represent areas of shelter and refuge for both anthropophilic and opportunistic species, such as Cx. quinquefasciatus and Ae. aegypti, as well as species that still need moderately preserved environments to develop.
    Keywords:  Diversity; green areas; mosquitoes; richness; seasonality
    DOI:  https://doi.org/10.2987/22-7108
  3. Malar J. 2023 Jun 06. 22(1): 176
    Composition of Anopheles species and bionomic characteristics over the peak malaria transmission season in Bandarban, Bangladesh.
    Hasan Mohammad Al-Amin, Isabella Rodriguez, Ching Swe Phru, Wasif A Khan, Rashidul Haque, Bernard L Nahlen, Timothy A Burton, Mohammad Shafiul Alam, Neil F Lobo.
      BACKGROUND: Joint efforts by government and non-government organizations have helped to reduce malaria in Bangladesh and set the country on a clear path to eventual malaria elimination. However, achieving that goal would be challenging without a comprehensive understanding of vector bionomics.METHODS: Targeted capturing of Anopheles mosquitoes over a rainy season, utilizing specific sampling methods, including human landing catches (HLCs), CDC-light traps (CDC-LTs), and pyrethrum spray catches (PSCs) were aimed to characterize entomological drivers of transmission in four sites of Bandarban, Bangladesh.
    RESULTS: Molecular characterization of a subset of 4637 mosquitoes has demonstrated the presence of at least 17 species whose capture rates were representative of the rainy season. Species compositions and bionomic traits did not vary between sites with Anopheles maculatus having the highest landing rate by HLCs and Anopheles vagus having the highest capture rate with CDC-LTs. Interestingly, Anopheles species compositions and capture rates varied significantly (p < 0.05) for An. vagus, between HLCs and its often-used proxy-CDC-LTs- suggesting impacts on downstream analysis. CDC-LTs capture rates demonstrated differing compositions with indoor and outdoor biting rates. For example, Anopheles nigerrimus and Anopheles nivipes were more endophagic by HLCs and more exophagic by CDC-LTs. The use of a cow-baited CDC-LT also demonstrated significantly different results when compared to a human-baited CDC-LT considering the high degree of anthropophily in these species. The exception to both zoophily and indoor resting was An. vagus, which demonstrated both anthropophily and high resting rates indoors-pointing to this species being a possible primary vector at this site.
    CONCLUSION: A diverse Anopheles fauna in Bandarban has been confirmed through molecular methods, highlighting the potential impact of sampling techniques. Given the complexity of the local ecosystem, a better understanding of mosquito behaviour and ecology is required to achieve the goal of malaria elimination in Bangladesh.
    Keywords:  Anopheles; Bangladesh; Bionomics; Human landing catch; Light trap
    DOI:  https://doi.org/10.1186/s12936-023-04614-2
  4. J Am Mosq Control Assoc. 2023 Jun 01.
    COUNTY RECORDS FOR AEDES JAPONICUS IN GEORGIA.
    Rosmarie Kelly, Thuy Vi Thi Nguyen, Misty McKanna, William J Sames.
      Consolidating and updating distributional data for mosquito species within a state is a good practice. These updates have an immediate impact by providing documented species distribution information for public use and by serving as a resource to researchers who need background information about a species's state distribution. In Georgia, Aedes japonicus, an introduced species, was peer review reported from 7 counties (2002-06): Fulton, Habersham, Lumpkin, Rabun, Towns, Union, and White. No further records were found in peer-reviewed journals or in the Symbiota Collections of Arthropods Network. This study consolidated the 7 peer-reviewed county records for Ae. japonicus with 73 new county records from surveillance data collected by the Georgia Department of Public Health. This study documented the presence of Ae. japonicus in 80 of the 159 counties in Georgia.
    Keywords:  Culicidae; distribution; mosquito; new records; surveillance
    DOI:  https://doi.org/10.2987/23-7117
  5. Am J Trop Med Hyg. 2023 Jun 05. pii: tpmd220495. [Epub ahead of print]
    The Threat of Vector-Borne Diseases in Sierra Leone.
    Robert T Jones, Scott J Tytheridge, Samuel J Smith, Rebecca S Levine, Mary H Hodges, Rashid Ansumana, Sophie Wulff, Jimmy Whitworth, James G Logan.
      Sierra Leone is vulnerable to a wide range of vector-borne diseases transmitted by mosquitoes, tsetse flies, black flies, and other vectors. Malaria, lymphatic filariasis, and onchocerciasis have posed the greatest threat and have received the most attention in terms of vector control and capacity for diagnosis. However, malaria infection rates remain high, and there is evidence of circulation of other vector-borne diseases, such as chikungunya and dengue, which may go undiagnosed and unreported. The limited understanding of the prevalence and transmission of these diseases restricts the capacity for predicting outbreaks, and impedes the planning of appropriate responses. We review the available literature and gather expert opinions from those working in the country to report on the status of vector-borne disease transmission and control in Sierra Leone, and present an assessment of the threats of these diseases. Our discussions highlight an absence of entomological testing for disease agents and the need for more investment in surveillance and capacity strengthening.
    DOI:  https://doi.org/10.4269/ajtmh.22-0495
  6. Int J Public Health. 2023 ;68 1605364
    Knowledge, Attitude and Practices Towards Dengue Fever Among Slum Dwellers: A Case Study in Dhaka City, Bangladesh.
    Md Mostafizur Rahman, Kamrun Nahar Tanni, Tuly Roy, Md Rakibul Islam, Md Alim Al Raji Rumi, Mohammed Sadman Sakib, Masrur Abdul Quader, Nafee-Ul-Islam Bhuiyan, Ifta Alam Shobuj, Afra Sayara Rahman, Md Iftekharul Haque, Fariha Faruk, Fahim Tahsan, Farzana Rahman, Edris Alam, Abu Reza Md Towfiqul Islam.
      Objectives: This study intends to evaluate Dhaka city slum dwellers' responses to Dengue fever (DF). Methods: 745 individuals participated in a KAP survey that was pre-tested. Face-to-face interviews were performed to obtain data. Python with RStudio was used for data management and analysis. The multiple regression models were applied when applicable. Results: 50% of respondents were aware of the deadly effects of DF, its common symptoms, and its infectious nature. However, many were unaware that DF could be asymptomatic, a previously infected person could have DF again, and the virus could be passed to a fetus. Individuals agreed that their families, communities, and authorities should monitor and maintain their environment to prevent Aedes mosquito breeding. However, overall 60% of the study group had inadequate preventative measures. Many participants lacked necessary practices such as taking additional measures (cleaning and covering the water storage) and monitoring potential breeding places. Education and types of media for DF information were shown to promote DF prevention practices. Conclusion: Slum dwellers lack awareness and preventative activities that put them at risk for DF. Authorities must improve dengue surveillance. The findings suggest efficient knowledge distribution, community stimulation, and ongoing monitoring of preventative efforts to reduce DF. A multidisciplinary approach is needed to alter dwellers' behavior since DF control can be done by raising the population's level of life. People and communities must perform competently to eliminate vector breeding sites.
    Keywords:  Bangladesh; COVID-19; Dhaka city; dengue; slums
    DOI:  https://doi.org/10.3389/ijph.2023.1605364
  7. BMC Pregnancy Childbirth. 2023 Jun 06. 23(1): 419
    Mosquito bed net use and associated factors among pregnant women in Rwanda: a nationwide survey.
    Joseph Kawuki, Elorm Donkor, Ghislaine Gatasi, Lilian Nuwabaine.
      BACKGROUND: In malaria-endemic countries such as Rwanda, the appropriate use of mosquito bed nets is an effective intervention for malaria prevention. Despite being one of the demographics most impacted by malaria, there is a dearth of literature on the usage of mosquito bed nets by pregnant women in Rwanda. The study aimed to assess the prevalence and associated factors for mosquito bed net use among pregnant women in Rwanda.METHODS: We used weighted data from the 2020 Rwanda Demographic and Health Survey of 870 pregnant women, and multistage stratified sampling was used to select participants. Multivariable logistic regression was conducted to determine the factors associated with mosquito bed net use, using SPSS (version 26).
    RESULTS: Of the 870 pregnant women, 57.9% (95%CI: 54.6-61.1) used mosquito bed nets. However, 16.7% did not use bed nets among those owning bed nets. On one hand, older age (AOR = 1.59, 95%CI: 1.04-2.44), primary education (AOR = 1.18, 95%CI: 1.07-2.23), being married (AOR = 2.17, 95%CI: 1.43-3.20), being from Kigali region (AOR = 1.97, 95%CI: 1.19-3.91), partner's education (AOR = 1.22, 95%CI: 1.13-3.41), having recently visited a health facility (AOR = 2.07, 95%CI: 1.35-3.18), and being in the third pregnancy trimester (AOR = 2.14, 95%CI: 1.44-3.18) were positively associated with mosquito bed net use. On the other hand, low wealth index (AOR = 0.13, 95%CI: 0.07-0.24), and being from Eastern region (AOR = 0.42, 95% CI: 0.26-0.66) had a negative association.
    CONCLUSIONS: About half of the pregnant women in Rwanda used mosquito bed nets and the usage was associated with various socio-demographics. There is a need for appropriate risk communication and continuous sensitisation to improve mosquito net use among pregnant women. Early antenatal care attendance and partner engagement in malaria prevention and mosquito net use, as well as consideration of household dynamics, are also crucial in improving not only mosquito net coverage but also utilization.
    Keywords:  Insecticide-treated nets; Mosquito bed net; Pregnant women; Rwanda; Usage
    DOI:  https://doi.org/10.1186/s12884-023-05583-9
  8. PLoS Negl Trop Dis. 2023 Jun 05. 17(6): e0011331
    Dengue in Myanmar: Spatiotemporal epidemiology, association with climate and short-term prediction.
    Win Zaw, Zaw Lin, July Ko Ko, Chawarat Rotejanaprasert, Neriza Pantanilla, Steeve Ebener, Richard James Maude.
      Dengue is a major public health problem in Myanmar. The country aims to reduce morbidity by 50% and mortality by 90% by 2025 based on 2015 data. To support efforts to reach these goals it is important to have a detailed picture of the epidemiology of dengue, its relationship to meteorological factors and ideally to predict ahead of time numbers of cases to plan resource allocations and control efforts. Health facility-level data on numbers of dengue cases from 2012 to 2017 were obtained from the Vector Borne Disease Control Unit, Department of Public Health, Myanmar. A detailed analysis of routine dengue and dengue hemorrhagic fever (DHF) incidence was conducted to examine the spatial and temporal epidemiology. Incidence was compared to climate data over the same period. Dengue was found to be widespread across the country with an increase in spatial extent over time. The temporal pattern of dengue cases and fatalities was episodic with annual outbreaks and no clear longitudinal trend. There were 127,912 reported cases and 632 deaths from 2012 and 2017 with peaks in 2013, 2015 and 2017. The case fatality rate was around 0.5% throughout. The peak season of dengue cases was from May to August in the wet season but in 2014 peak dengue season continued until November. The strength of correlation of dengue incidence with different climate factors (total rainfall, maximum, mean and minimum temperature and absolute humidity) varied between different States and Regions. Monthly incidence was forecasted 1 month ahead using the Auto Regressive Integrated Moving Average (ARIMA) method at country and subnational levels. With further development and validation, this may be a simple way to quickly generate short-term predictions at subnational scales with sufficient certainty to use for intervention planning.
    DOI:  https://doi.org/10.1371/journal.pntd.0011331
  9. Rev Saude Publica. 2023 ;pii: S0034-89102023000100224. [Epub ahead of print]57 32
    High-risk spatial clusters for Zika, dengue, and chikungunya in Rio de Janeiro, Brazil.
    Reinaldo Souza-Santos, Andrea Sobral, Andre Reynaldo Santos Périssé.
      OBJECTIVE: To analyze the spatial distribution and identify high-risk spatial clusters of Zika, dengue, and chikungunya (ZDC), in the city of Rio de Janeiro, Brazil, and their socioeconomic status.METHODS: An ecological study based on data from a seroprevalence survey. Using a rapid diagnostic test to detect the arboviruses, 2,114 individuals were tested in 2018. The spatial distribution was analyzed using kernel estimation. To detect high-risk spatial clusters of arboviruses, we used multivariate scan statistics. The Social Development Index (SDI) was considered in the analysis of socioeconomic status.
    RESULTS: Among the 2,114 individuals, 1,714 (81.1%) were positive for at least one arbovirus investigated. The kernel estimation showed positive individuals for at least one arbovirus in all regions of the city, with hot spots in the North, coincident with regions with very low or low SDI. The scan statistic detected three significant (p<0.05) high-risk spatial clusters for Zika, dengue, and chikungunya viruses. These clusters correspond to 35.7% (n=613) of all positive individuals of the sample. The most likely cluster was in the North (cluster 1) and overlapped regions with very low and low SDI. Clusters 2 and 3 were in the West and overlapping regions with low and very low SDI, respectively. The highest values of relative risks were in cluster 1 for CHIKV (1.97), in cluster 2 for ZIKV (1.58), and in cluster 3 for CHIKV (1.44). Regarding outcomes in the clusters, the Flavivirus had the highest frequency in clusters 1, 2, and 3 (42.83%, 54.46%, and 52.08%, respectively).
    CONCLUSION: We found an over-risk for arboviruses in areas with the worst socioeconomic conditions in Rio de Janeiro. Moreover, the highest concentration of people negative for arboviruses occurred in areas considered to have better living conditions.
    DOI:  https://doi.org/10.11606/s1518-8787.2023057004932
  10. PLoS Negl Trop Dis. 2023 Jun 05. 17(6): e0011407
    Ecological drivers of sustained enzootic yellow fever virus transmission in Brazil, 2017-2021.
    Natália Ingrid Oliveira Silva, Gregory F Albery, Matheus Soares Arruda, Gabriela Fernanda Garcia Oliveira, Thaís Alkifeles Costa, Érica Munhoz de Mello, Gabriel Dias Moreira, Erik Vinícius Reis, Simone Agostinho da Silva, Marlise Costa Silva, Munique Guimarães de Almeida, Daniel J Becker, Colin J Carlson, Nikos Vasilakis, Kathryn A Hanley, Betânia Paiva Drumond.
      Beginning December 2016, sylvatic yellow fever (YF) outbreaks spread into southeastern Brazil, and Minas Gerais state experienced two sylvatic YF waves (2017 and 2018). Following these massive YF waves, we screened 187 free-living non-human primate (NHPs) carcasses collected throughout the state between January 2019 and June 2021 for YF virus (YFV) using qPCR. One sample belonging to a Callithrix, collected in June 2020, was positive for YFV. The viral strain belonged to the same lineage associated with 2017-2018 outbreaks, showing the continued enzootic circulation of YFV in the state. Next, using data from 781 NHPs carcasses collected in 2017-18, we used generalized additive mixed models (GAMMs) to identify the spatiotemporal and host-level drivers of YFV infection and intensity (an estimation of genomic viral load in the liver of infected NHP). Our GAMMs explained 65% and 68% of variation in virus infection and intensity, respectively, and uncovered strong temporal and spatial patterns for YFV infection and intensity. NHP infection was higher in the eastern part of Minas Gerais state, where 2017-2018 outbreaks affecting humans and NHPs were concentrated. The odds of YFV infection were significantly lower in NHPs from urban areas than from urban-rural or rural areas, while infection intensity was significantly lower in NHPs from urban areas or the urban-rural interface relative to rural areas. Both YFV infection and intensity were higher during the warm/rainy season compared to the cold/dry season. The higher YFV intensity in NHPs in warm/rainy periods could be a result of higher exposure to vectors and/or higher virus titers in vectors during this time resulting in the delivery of a higher virus dose and higher viral replication levels within NHPs. Further studies are needed to better test this hypothesis and further compare the dynamics of YFV enzootic cycles between different seasons.
    DOI:  https://doi.org/10.1371/journal.pntd.0011407
This page is being maintained by Thomas Krichel. It was last updated on 2023‒10‒31 at 17:30.