bims-mosdis 2022-09-25 papers

bims-mosdis

Biomed News

on Mosquito distribution and disease

Issue of 2022–09–25
nineteen papers selected by
Richard Halfpenny, Staffordshire University

Compounds from human odor induce attraction and landing in female yellow fever mosquitoes (Aedes aegypti).
Mass Trapping and Larval Source Management for Mosquito Elimination on Small Maldivian Islands.
Spatial and Temporal Distribution of Aedes aegypti and Aedes albopictus Oviposition on the Coast of Paraná, Brazil, a Recent Area of Dengue Virus Transmission.
Relative Influence of Land Use, Mosquito Abundance, and Bird Communities in Defining West Nile Virus Infection Rates in Culex Mosquito Populations.
[Distribution of mosquito species and associated viruses in Hami City of Xinjiang Uygur Autonomous Region from 2019 to 2020].
First report of two Asian invasive mosquito species, Aedes japonicus and Aedes koreicus, in Piedmont, northwest Italy.
Gene drive mosquitoes can aid malaria elimination by retarding Plasmodium sporogonic development.
Effects of Hibernation Site, Temperature, and Humidity on the Abundance and Survival of Overwintering Culex pipiens pipiens and Anopheles messeae (Diptera: Culicidae).
Mosquito (Diptera: Culicidae) Diversity and Community Structure in Doi Inthanon National Park, Northern Thailand.
First report of the blood-feeding pattern in Aedes koreicus, a new invasive species in Europe.
Spatial and Seasonal Patterns of the Mosquito Community in Central Oklahoma.
Vertical Transmission of Sindbis Virus in Culex Mosquitoes.
Spatiotemporal patterns of dengue and Zika incidence during the 2015-2018 outbreak of Zika in Mexico.
House modifications for preventing malaria.
Batai Orthobunyavirus: An Emerging Mosquito-Borne Virus in Europe.
Spatio-temporal distribution of vector borne diseases in Australia and Papua New Guinea vis-à-vis climatic factors.
Predictable Chikungunya Infection Dynamics in Brazil.
Spatiotemporal variation of malaria incidence in parasite clearance interventions and non-intervention areas in the Amhara Regional State, Ethiopia.
An overview of dengue viral infection circulating in Pakistan.

Sci Rep. 2022 Sep 21. 12(1): 15638

Compounds from human odor induce attraction and landing in female yellow fever mosquitoes (Aedes aegypti).

Jan E Bello, Ring T Cardé.

The female Aedes aegypti mosquito is a vector of many human diseases such as yellow fever, dengue, and Zika. Transmission of these viruses occurs when an infected female mosquito locates a suitable human host, alights, and blood feeds. Aedes aegypti use human-emitted odors, as well as heat and visual cues, for host location. However, none of the previously identified human-produced compounds induce significant orientation and landing on a human host. Here we show that female yellow fever mosquitoes orient to and land on a mixture of compounds identified from human skin rubbings. Using odor collection, extraction, a two-choice, bioassay-guided fractionation, and chemical analysis, we identified mixtures of 2-ketoglutaric acid and L-lactic acid as landing attractants for female Ae. aegypti. The mixture of pyruvic acid and L-lactic acid were also found to be weakly attractive. Using ratio-response assays, we found that the attraction and alighting behaviors of the mosquitoes were directly related to the ratio of these compounds presented on the surface of the glass assay beads, suggesting that these compounds could mediate landing on a human host even at sub-nanogram dosages. The newly identified compounds fill a gap in our knowledge of odor-mediated attraction of Ae. aegypti and may lead to the development of new attractant-based mosquito control tactics.

DOI: https://doi.org/10.1038/s41598-022-19254-w
Insects. 2022 Sep 02. pii: 805. [Epub ahead of print]13(9):

Mass Trapping and Larval Source Management for Mosquito Elimination on Small Maldivian Islands.

Akib Jahir, Najat F Kahamba, Tom O Knols, Gordon Jackson, Nila F A Patty, Sonu Shivdasani, Fredros O Okumu, Bart G J Knols.

  Globally, environmental impacts and insecticide resistance are forcing pest control organizations to adopt eco-friendly and insecticide-free alternatives to reduce the risk of mosquito-borne diseases, which affect millions of people, such as dengue, chikungunya or Zika virus. We used, for the first time, a combination of human odor-baited mosquito traps (at 6.0 traps/ha), oviposition traps (7.2 traps/ha) and larval source management (LSM) to practically eliminate populations of the Asian tiger mosquito Aedes albopictus (peak suppression 93.0% (95% CI 91.7-94.4)) and the Southern house mosquito Culex quinquefasciatus (peak suppression 98.3% (95% CI 97.0-99.5)) from a Maldivian island (size: 41.4 ha) within a year and thereafter observed a similar collapse of populations on a second island (size 49.0 ha; trap densities 4.1/ha and 8.2/ha for both trap types, respectively). On a third island (1.6 ha in size), we increased the human odor-baited trap density to 6.3/ha and then to 18.8/ha (combined with LSM but without oviposition traps), after which the Aedes mosquito population was eliminated within 2 months. Such suppression levels eliminate the risk of arboviral disease transmission for local communities and safeguard tourism, a vital economic resource for small island developing states. Terminating intense insecticide use (through fogging) benefits human and environmental health and restores insect biodiversity, coral reefs and marine life in these small and fragile island ecosystems. Moreover, trapping poses a convincing alternative to chemical control and reaches impact levels comparable to contemporary genetic control strategies. This can benefit numerous communities and provide livelihood options in small tropical islands around the world where mosquitoes pose both a nuisance and disease threat.

Keywords:  arbovirus; elimination; islands; larval source management; mosquito; trapping

DOI:  https://doi.org/10.3390/insects13090805
Trop Med Infect Dis. 2022 Sep 14. pii: 246. [Epub ahead of print]7(9):

Spatial and Temporal Distribution of Aedes aegypti and Aedes albopictus Oviposition on the Coast of Paraná, Brazil, a Recent Area of Dengue Virus Transmission.

Silvia Jaqueline Pereira de Souza, André de Camargo Guaraldo, Nildimar Alves Honório, Daniel Cardoso Portela Câmara, Natali Mary Sukow, Sarita Terezinha Machado, Claudia Nunes Duarte Dos Santos, Magda Clara Vieira da Costa-Ribeiro.

  Aedes aegypti and Aedes albopictus are considered the most important vectors of arboviruses in the world. Aedes aegypti is the primary vector of dengue, urban yellow fever, chikungunya and zika in Brazil, and Ae. albopictus is considered a potential vector. Distribution patterns and the influence of climatic variables on the oviposition of Ae. aegypti and Ae. albopictus were evaluated in Morretes, a tourist city in the coastal area of Paraná State, Brazil, which has recently been experiencing cases of dengue fever. Eggs were collected using ovitraps over a period of one year (September 2017 to September 2018) and reared from hatching until the emergence of the adults. Both Aedes species were found in anthropized areas with a high human density index. Findings suggest that the monthly average temperature (LRT = 16.65, p = 0.001) had significant positive influences on the oviposition of the Aedes species. Considering the wide distribution of DENV around the Paraná coast and the presence of Ae. albopictus alongside Ae. aegypti, studies on natural arbovirus infection patterns and seasonality are recommended in the region.

Keywords:  Aedes aegypti; Aedes albopictus; meteorological factors; occurrence; oviposition; spatial distribution

DOI:  https://doi.org/10.3390/tropicalmed7090246
Insects. 2022 Aug 23. pii: 758. [Epub ahead of print]13(9):

Relative Influence of Land Use, Mosquito Abundance, and Bird Communities in Defining West Nile Virus Infection Rates in Culex Mosquito Populations.

James S Adelman, Ryan E Tokarz, Alec E Euken, Eleanor N Field, Marie C Russell, Ryan C Smith.

  Since its introduction to North America in 1999, the West Nile virus (WNV) has resulted in over 50,000 human cases and 2400 deaths. WNV transmission is maintained via mosquito vectors and avian reservoir hosts, yet mosquito and avian infections are not uniform across ecological landscapes. As a result, it remains unclear whether the ecological communities of the vectors or reservoir hosts are more predictive of zoonotic risk at the microhabitat level. We examined this question in central Iowa, representative of the midwestern United States, across a land use gradient consisting of suburban interfaces with natural and agricultural habitats. At eight sites, we captured mosquito abundance data using New Jersey light traps and monitored bird communities using visual and auditory point count surveys. We found that the mosquito minimum infection rate (MIR) was better predicted by metrics of the mosquito community than metrics of the bird community, where sites with higher proportions of Culex pipiens group mosquitoes during late summer (after late July) showed higher MIRs. Bird community metrics did not significantly influence mosquito MIRs across sites. Together, these data suggest that the microhabitat suitability of Culex vector species is of greater importance than avian community composition in driving WNV infection dynamics at the urban and agricultural interface.

Keywords:  Culex mosquitoes; West Nile virus; bird communities; mosquito surveillance; vector-borne disease ecology

DOI:  https://doi.org/10.3390/insects13090758
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi. 2022 Aug 25. 34(4): 392-395

[Distribution of mosquito species and associated viruses in Hami City of Xinjiang Uygur Autonomous Region from 2019 to 2020].

Z G Gao, D Wang, M T Mahe, Z X Cao, Y Liu, T Lina, R F Huang, X Ma.

   OBJECTIVE: To investigate the distribution of mosquito species and their associated viruses, and identify Culex pipiens subspecies in Hami City, Xinjiang Uygur Autonomous Region.
METHODS: Mosquitoes were captured using mosquito trapping lamps method in Yizhou District, Yiwu County, and Balikun County of Hami City in mi-July, 2019 and 2020. The species and subspecies of all captured mosquitoes were characterized. In addition, the flavivirus, alphavirus, bunyavirus, Japanese encephalitis virus, Liaoning virus, Tahyna virus, tick-borne encephalitis virus and West Nile virus were detected using reverse-transcription PCR assay in captured mosquitoes.
RESULTS: A total of 1 496 mosquitoes were captured from Yizhou District, Yiwu County, and Balikun County of Hami City, belonging to 3 genus and 3 species. Cx. pipiens was the dominant mosquito species (986 mosquitoes, 65.91%), followed by Aedes caspius (457 mosquitoes, 30.55%), while Culiseta alaskaensis had the lowest number (53 mosquitoes, 3.54%). All captured Cx. pipiens mosquitoes were identified as Cx. pipiens pipiens based on the terminalia of male mosquitoes. RT-PCR assay tested negative for flavivirus, alphavirus, bunyavirus, Japanese encephalitis virus, Liaoning virus, Tahyna virus, tick-borne encephalitis or West Nile virus in captured Cx. pipiens mosquitoes.
CONCLUSIONS: There were 3 species of mosquitoes in Hami City from 2019 to 2020, including Cx. pipiens, Ae. Caspius and C. alaskaensis, with Cx. pipiens as the dominant mosquito species, and all captured Cx. pipiens mosquitoes were Cx. pipiens pipiens; however, no arboviruses were detected.

Keywords:  Arbovirus; Culex pipiens; Hami City; Mosquito; Species identification

DOI:  https://doi.org/10.16250/j.32.1374.2022085
Ann Ist Super Sanita. 2022 Jul-Sep;58(3):58(3): 162-165

First report of two Asian invasive mosquito species, Aedes japonicus and Aedes koreicus, in Piedmont, northwest Italy.

Andrea Mosca, Mirko F Perna, Matteo Giovannozzi, Paolo Roberto.

INTRODUCTION: Aedes japonicus japonicus and Aedes koreicus are two invasive mosquitoes recently reported in various parts of Europe, including areas very close to Piedmont where, since 2012, specific tools have been implemented to allow the early detection of invasive mosquitoes, through the surveillance of the main points of entry.
RESULTS: Thanks to the regional surveillance system, Ae. j. japonicus was intercepted in Piedmont for the first time in 2019, in the northernmost part of the region and now it is reported in six provinces. Ae. koreicus was intercepted for the first time in 2012 in three provinces.
DISCUSSION AND CONCLUSION: The spread of these two invasive mosquitoes in Europe is still ongoing. Where Aedes albopictus is abundant, probably their presence goes undetected, therefore, it is crucial to begin surveillance early in the season. Due to their competence for several arboviruses and tolerance to the cold temperatures Ae. j. japonicus and Ae. koreicus represent a further concern for Public Health. A longer seasonal period for surveillance and response to mosquito-borne diseases, as well as a shift up of these activities to previously uncovered altitudes are indeed needed.

DOI: https://doi.org/10.4415/ANN_22_03_03
Sci Adv. 2022 Sep 23. 8(38): eabo1733

Gene drive mosquitoes can aid malaria elimination by retarding Plasmodium sporogonic development.

Astrid Hoermann, Tibebu Habtewold, Prashanth Selvaraj, Giuseppe Del Corsano, Paolo Capriotti, Maria Grazia Inghilterra, Temesgen M Kebede, George K Christophides, Nikolai Windbichler.

Gene drives hold promise for the genetic control of malaria vectors. The development of vector population modification strategies hinges on the availability of effector mechanisms impeding parasite development in transgenic mosquitoes. We augmented a midgut gene of the malaria mosquito Anopheles gambiae to secrete two exogenous antimicrobial peptides, magainin 2 and melittin. This small genetic modification, capable of efficient nonautonomous gene drive, hampers oocyst development in both Plasmodium falciparum and Plasmodium berghei. It delays the release of infectious sporozoites, while it simultaneously reduces the life span of homozygous female transgenic mosquitoes. Modeling the spread of this modification using a large-scale agent-based model of malaria epidemiology reveals that it can break the cycle of disease transmission across a range of transmission intensities.

DOI: https://doi.org/10.1126/sciadv.abo1733
J Med Entomol. 2022 Sep 20. pii: tjac139. [Epub ahead of print]

Effects of Hibernation Site, Temperature, and Humidity on the Abundance and Survival of Overwintering Culex pipiens pipiens and Anopheles messeae (Diptera: Culicidae).

F G Sauer, E Timmermann, U Lange, R Lühken, E Kiel.

  Knowledge of the hibernation site preferences and the factors which influence winter survival in these hibernation sites may enhance understanding of mosquito population dynamics after winter and how arboviruses persist in temperate regions. Our study quantified the number of adult overwintering mosquitoes in cellars and aboveground constructions and analyzed survival rates in relation to the environmental conditions in these sites. During the winters 2016/2017 and 2018/2019, 149 different constructions in Northwest Germany were sampled for mosquitoes. Mosquitoes were detected in 44% of the cellars and in 33% of the aboveground constructions. Culex p. pipiens Linnaeus was the most abundant species in cellars, whereas high numbers of Anopheles messeae Falleroni were collected from a single barn. Subsequently, an enclosure study was conducted during 2019/2020. Overwintering field-collected Cx. p. pipiens and An. messeae were divided into groups with or without fructose availability, and placed in cages with different man-made hibernations sites, where temperature and relative humidity were recorded hourly. For both species, increasing mean temperatures (5-16°C) but not mean relative humidity (58-94%) were correlated with winter mortality rates of the mosquitoes. The lipid measurements were greater and mortality rates were lower when both species were provided fructose. Larger specimens (determined by wing length) stored more lipids, and in Cx. p pipiens, but not in An. messeae, survival probability of large specimens was significantly greater than for small females. Mosquitoes showed a distinct pattern in the selection of overwintering sites, while temperature was an important driver for survival.

Keywords:   Anopheles messeae ; Culex pipiens pipiens ; Culicidae; hibernation site; winter mortality

DOI:  https://doi.org/10.1093/jme/tjac139
Insects. 2022 Sep 07. pii: 814. [Epub ahead of print]13(9):

Mosquito (Diptera: Culicidae) Diversity and Community Structure in Doi Inthanon National Park, Northern Thailand.

Wichai Srisuka, Chayanit Sulin, Wirat Sommitr, Rampa Rattanarithikul, Kittipat Aupalee, Atiporn Saeung, Ralph E Harbach.

  Urbanization and human activities create new suitable aquatic habitats for the immature stages of mosquitoes in many countries. This also applies to Doi Inthanon National Park in northern Thailand, which is named for the highest mountain in the country. Despite its popularity, there is no information regarding mosquito diversity and community structure in the different ecosystems of the park. Monthly collections of immature stages from various habitats were conducted from August 2004 to December 2005 using dipping and sucking methods. The specimens collected from each habitat were reared to adults and identified based on their morphology. Diversity parameters and community structure were statistically analyzed. A total of 140 species (3795 specimens) belonging to 15 genera were identified. Among these, four genera (Culex, Aedes, Anopheles, and Uranotaenia) had high species richness, each represented by 48, 27, 19, and 15 species, respectively. Aedes albopictus was the most relatively abundant species, representing 6.7% of the total number of captured specimens, followed by Tripteroides aranoides (5.6%) and Cx. mimulus (5%). Species richness in natural habitats was significantly higher than in artificial containers. Species richness and abundance were highest in the rainy season. In comparison to agricultural areas and villages, mosquito diversity was found to be higher in forest areas. Ground pools, stream pools, rock pools, bamboo stumps, bamboo internode, and rice fields were the most preferred natural habitats. The results indicate that Doi Inthanon National Park has a high mosquito diversity. Each species exhibits differences in abundance and distribution in different habitats, which is useful information for planning conservation measures and vector control in the park.

Keywords:  distribution; ecology; mosquito fauna; mountain; vectors

DOI:  https://doi.org/10.3390/insects13090814
Sci Rep. 2022 Sep 21. 12(1): 15751

First report of the blood-feeding pattern in Aedes koreicus, a new invasive species in Europe.

Fabrizio Montarsi, Fausta Rosso, Daniele Arnoldi, Silvia Ravagnan, Giovanni Marini, Luca Delucchi, Roberto Rosà, Annapaola Rizzoli.

Aedes koreicus is an invasive mosquito species which has been introduced into several European countries. Compared to other invasive Aedes mosquitoes, little is known of its biology and ecology. To determine Ae. koreicus' vectorial capacity, it is essential to establish its feeding patterns and level of anthropophagy. We report on the blood-feeding patterns of Ae. koreicus, examining the blood meal origin of engorged females and evaluating the influence of different biotic and abiotic factors on feeding behavior. Mosquitoes were collected in 23 sites in northern Italy by manual aspiration and BG-sentinel traps; host availability was estimated by survey. The source of blood meals was identified using a nested PCR and by targeting and sequencing the cytochrome c oxidase subunit I gene. In total, 352 Ae. koreicus engorged females were collected between 2013 and 2020 and host blood meals were determined from 299 blood-fed mosquitoes (84.9%). Eleven host species were identified, with the highest prevalences being observed among roe deer (Capreolus capreolus) (N = 189, 63.2%) and humans (N = 46, 15.4%). Blood meals were mostly taken from roe deer in forested sites and from humans in urban areas, suggesting that this species can feed on different hosts according to local abundance. Two blood meals were identified from avian hosts and one from lizard. Ae. koreicus' mammalophilic feeding pattern suggests that it may be a potential vector of pathogens establishing transmission cycles among mammals, whereas its role as a bridge vector between mammals and birds could be negligible.

DOI: https://doi.org/10.1038/s41598-022-19734-z
Pathogens. 2022 Sep 03. pii: 1007. [Epub ahead of print]11(9):

Spatial and Seasonal Patterns of the Mosquito Community in Central Oklahoma.

David Hoekman, Bailee Cummings, Helen Arango, Nicholas Back, Randall Welles, Noah Pelletier, Katelyn Helwig, Christian Escritt, Kayla Thomas, Hailie Fellers, Callie Campbell, Alyssa Wheeler, Raul Iglesias, Hayden Jacobs, Macey Lively, Caio Martinelle B França.

  Mosquitoes (Culicidae) are ubiquitous flying insects that function as vectors for several viruses that cause disease in humans. Mosquito abundance and diversity are influenced by landscape features and environmental factors such as temperature and precipitation and vary across seasons and years. The range and phenology of many mosquito species that vector viruses relevant to human health are changing. We sampled mosquito communities in central Oklahoma for four years at thirteen sites, collecting over 25,000 mosquitoes; among these, we identified 27 different species, including several that transmit human pathogens and were collected in suburban backyards. Community composition differed across the landscape and changed from early season to late season and year to year. This effort to describe mosquito communities in Oklahoma is a first step toward assessing and predicting arbovirus risk, an ongoing and dynamic public health challenge.

Keywords:  Aedes; CDC light trap; Culex; Oklahoma; community composition; mosquito; surveillance; vectors

DOI:  https://doi.org/10.3390/pathogens11091007
Viruses. 2022 Aug 30. pii: 1915. [Epub ahead of print]14(9):

Vertical Transmission of Sindbis Virus in Culex Mosquitoes.

Emma Dahl, Linnea Öborn, Viktoria Sjöberg, Åke Lundkvist, Jenny C Hesson.

  Vertical transmission (VT) is a phenomenon of vector-borne diseases where a pathogen is transferred from an infected arthropod mother to her offspring. For mosquito-borne flavi- and alphaviruses, VT is commonly viewed as rare; however, both field and experimental studies report on vertical transmission efficiency to a notably varying degree. It is likely that this reflects the different experimental methods used to test vertical transmission efficiency as well as differences between virus-vector combinations. There are very few investigations of the VT of an alphavirus in a Culex vector. Sindbis virus (SINV) is an arthritogenic alphavirus that utilizes Culex species as main vectors both in the summer transmission season and for its persistence over the winter period in northern latitudes. In this study, we investigated the vertical transmission of the SINV in Culex vectors, both in the field and in experimental settings. The detection of SINV RNA in field-collected egg rafts and emerging adults shows that vertical transmission takes place in the field. Experimentally infected females gave rise to adult offspring containing SINV RNA at emergence; however, three to four weeks after emergence none of the offspring contained SINV RNA. This study shows that vertical transmission may be connected to SINV's ability to persist throughout northern winters and also highlights many aspects of viral replication that need further study.

Keywords:  Sweden; alphavirus; arbovirus; overwintering; temperate region; vector; viral persistence; winter season

DOI:  https://doi.org/10.3390/v14091915
Salud Publica Mex. 2022 Aug 19. 64(5, sept-oct): 478-487

Spatiotemporal patterns of dengue and Zika incidence during the 2015-2018 outbreak of Zika in Mexico.

Anais Cortes-Escamilla, Benjamín Roche, Mario Henry Rodríguez-López, Hugo López Gatell-Ramírez, Celia M Alpuche-Aranda.

OBJECTIVE: Evaluate spatially and temporally simultaneous presence of clusters of dengue and Zika clinical cases and their relationship with expected dengue transmission risk.
MATERIALS AND METHODS: A classification of dengue risk transmission was carried out for whole country, and spatial autocorrelation analyses to identify clusters of confirmed clinical cases of dengue and Zika from 2015 to 2018 was conducted using Moran's Index statistics.
RESULTS: Clusters of both diseases were identified in dengue-high risk munici-palities at the beginning of the outbreak, but, at the end of the outbreak, Zika clusters occurred in dengue low-risk mu-nicipalities.
CONCLUSION: This study identified Zika clusters in low-risk dengue areas suggesting participation of several factors that favor virus introduction and dissemination, such as differences in entomological and control interventions, and the possibility of cross-immunity in the population.

DOI: https://doi.org/10.21149/13584
Cochrane Database Syst Rev. 2022 Sep 22. 9 CD013398

House modifications for preventing malaria.

Tilly Fox, Joanna Furnival-Adams, Marty Chaplin, Mark Napier, Evelyn A Olanga.

BACKGROUND: Malaria remains an important public health problem. Research in 1900 suggested house modifications may reduce malaria transmission. A previous version of this review concluded that house screening may be effective in reducing malaria. This update includes data from five new studies.
OBJECTIVES: To assess the effects of house modifications that aim to reduce exposure to mosquitoes on malaria disease and transmission.
SEARCH METHODS: We searched the Cochrane Infectious Diseases Group Specialized Register; Central Register of Controlled Trials (CENTRAL), published in the Cochrane Library; MEDLINE (PubMed); Embase (OVID); Centre for Agriculture and Bioscience International (CAB) Abstracts (Web of Science); and the Latin American and Caribbean Health Science Information database (LILACS) up to 25 May 2022. We also searched the World Health Organization International Clinical Trials Registry Platform, ClinicalTrials.gov, and the ISRCTN registry to identify ongoing trials up to 25 May 2022.
SELECTION CRITERIA: Randomized controlled trials, including cluster-randomized controlled trials (cRCTs), cross-over studies, and stepped-wedge designs were eligible, as were quasi-experimental trials, including controlled before-and-after studies, controlled interrupted time series, and non-randomized cross-over studies. We sought studies investigating primary construction and house modifications to existing homes reporting epidemiological outcomes (malaria case incidence, malaria infection incidence or parasite prevalence). We extracted any entomological outcomes that were also reported in these studies.
DATA COLLECTION AND ANALYSIS: Two review authors independently selected eligible studies, extracted data, and assessed the risk of bias. We used risk ratios (RR) to compare the effect of the intervention with the control for dichotomous data. For continuous data, we presented the mean difference; and for count and rate data, we used rate ratios. We presented all results with 95% confidence intervals (CIs). We assessed the certainty of evidence using the GRADE approach.
MAIN RESULTS: One RCT and six cRCTs met our inclusion criteria, with an additional six ongoing RCTs. We did not identify any eligible non-randomized studies. All included trials were conducted in sub-Saharan Africa since 2009; two randomized by household and four at the block or village level. All trials assessed screening of windows, doors, eaves, ceilings, or any combination of these; this was either alone, or in combination with roof modification or eave tube installation (an insecticidal "lure and kill" device that reduces mosquito entry whilst maintaining some airflow). In one trial, the screening material was treated with 2% permethrin insecticide. In five trials, the researchers implemented the interventions. A community-based approach was adopted in the other trial. Overall, the implementation of house modifications probably reduced malaria parasite prevalence (RR 0.68, 95% CI 0.57 to 0.82; 5 trials, 5183 participants; moderate-certainty evidence), although an inconsistent effect was observed in a subpopulation of children in one study. House modifications reduced moderate to severe anaemia prevalence (RR 0.70, 95% CI 0.55 to 0.89; 3 trials, 3643 participants; high-certainty evidence). There was no consistent effect on clinical malaria incidence, with rate ratios ranging from 0.38 to 1.62 (3 trials, 3365 participants, 4126.6 person-years). House modifications may reduce indoor mosquito density (rate ratio 0.63, 95% CI 0.30 to 1.30; 4 trials, 9894 household-nights; low-certainty evidence), although two studies showed little effect on this parameter.
AUTHORS' CONCLUSIONS: House modifications - largely screening, sometimes combined with insecticide and lure and kill devices - were associated with a reduction in malaria parasite prevalence and a reduction in people with anaemia. Findings on malaria incidence were mixed. Modifications were also associated with lower indoor adult mosquito density, but this effect was not present in some studies.

DOI: https://doi.org/10.1002/14651858.CD013398.pub4
Viruses. 2022 Aug 25. pii: 1868. [Epub ahead of print]14(9):

Batai Orthobunyavirus: An Emerging Mosquito-Borne Virus in Europe.

Karen L Mansfield, Arran J Folly, Luis M Hernández-Triana, Sanam Sewgobind, Nicholas Johnson.

  Batai virus (BATV) is a zoonotic orthobunyavirus transmitted by a wide range of mosquito vectors. The virus is distributed throughout Asia and parts of Africa and has been sporadically detected in several European countries. There is increasing evidence that BATV is emerging in Europe as a potential threat to both animal and human health, having been detected in mosquitoes, mammals, birds and humans. In recent years, serological surveillance in cattle, sheep and goats has suggested an antibody prevalence of up to 46% in European livestock, although human serological prevalence remains generally low. However, the recent and continued spread of invasive mosquito species into Europe may facilitate the establishment of competent populations of mosquitoes leading to increased BATV transmission. Migratory birds may also potentially facilitate the emergence of BATV in geographical locations where it was previously undetected. Although BATV has the potential to cause disease in humans and livestock, our understanding of the impact in wild animal populations is extremely limited. Therefore, there is a need for increased surveillance for BATV in mosquitoes, livestock, wild mammals and birds in Europe to understand the true impact of this virus.

Keywords:  Chittoor; emerging infectious diseases; zoonotic; Čalovo

DOI:  https://doi.org/10.3390/v14091868
J Vector Borne Dis. 2022 Apr-Jun;59(2):59(2): 115-126

Spatio-temporal distribution of vector borne diseases in Australia and Papua New Guinea vis-à-vis climatic factors.

Yuriy Kuleshov, Yufei Wei, Kasis Inape, Gang-Jun Liu.

   BACKGROUND & OBJECTIVES: Weather and climate are directly linked to human health including the distribution and occurrence of vector-borne diseases which are of significant concern for public health.
METHODS: In this review, studies on spatiotemporal distribution of dengue, Barmah Forest Virus (BFV) and Ross River Virus (RRV) in Australia and malaria in Papua New Guinea (PNG) under the influence of climate change and/ or human society conducted in the past two decades were analysed and summarised. Environmental factors such as temperature, rainfall, relative humidity and tides were the main contributors from climate.
RESULTS: The Socio-Economic Indexes for Areas (SEIFA) index (a product from the Australian Bureau of Statistics that ranks areas in Australia according to relative socio-economic advantage and disadvantage) was important in evaluating contribution from human society.
INTERPRETATION & CONCLUSION: For future studies, more emphasis on evaluation of impact of the El Niño-Southern Oscillation (ENSO) and human society on spatio-temporal distribution of vector borne diseases is recommended to highlight importance of the environmental factors in spreading mosquito-borne diseases in Australia and PNG.

Keywords:  Barmah Forest Virus; Climate Change; Dengue; Malaria; Ross River Virus; Socioeconomic Factors; Vector-Borne Diseases

DOI:  https://doi.org/10.4103/0972-9062.337510
Viruses. 2022 Aug 26. pii: 1889. [Epub ahead of print]14(9):

Predictable Chikungunya Infection Dynamics in Brazil.

Laith Yakob.

  Chikungunya virus (CHIKV) was first imported into the Caribbean in 2013 and subsequently spread across the Americas. It has infected millions in the region and Brazil has become the hub of ongoing transmission. Using Seasonal Autoregressive Integrated Moving Average (SARIMA) models trained and validated on Brazilian data from the Ministry of Health's notifiable diseases information system, we tested the hypothesis that transmission in Brazil had transitioned from sporadic and explosive to become more predictable. Consistency weighted, population standardized kernel density estimates were used to identify municipalities with the most consistent inter-annual transmission rates. Spatial clustering was assessed per calendar month for 2017-2021 inclusive using Moran's I. SARIMA models were validated on 2020-2021 data and forecasted 106,162 (95%CI 27,303-200,917) serologically confirmed cases and 339,907 (95%CI 35,780-1035,449) total notifications for 2022-2023 inclusive, with >90% of cases in the Northeast and Southeast regions. Comparing forecasts for the first five months of 2022 to the most up-to-date ECDC report (published 2 June 2022) showed remarkable accuracy: the models predicted 92,739 (95%CI 20,685-195,191) case notifications during which the ECDC reported 92,349 case notifications. Hotspots of consistent transmission were identified in the states of Para and Tocantins (North region); Rio Grande do Norte, Paraiba and Pernambuco (Northeast region); and Rio de Janeiro and eastern Minas Gerais (Southeast region). Significant spatial clustering peaked during late summer/early autumn. This analysis highlights how CHIKV transmission in Brazil has transitioned, making it more predictable and thus enabling improved control targeting and site selection for trialing interventions.

Keywords:  Aedes; arbovirus; epidemiology; intervention; transmission

DOI:  https://doi.org/10.3390/v14091889
PLoS One. 2022 ;17(9): e0274500

Spatiotemporal variation of malaria incidence in parasite clearance interventions and non-intervention areas in the Amhara Regional State, Ethiopia.

Melkamu Tiruneh Zeleke, Kassahun Alemu Gelaye, Muluken Azage Yenesew.

BACKGROUND: In Ethiopia, malaria remains a major public health problem. To eliminate malaria, parasite clearance interventions were implemented in six kebeles (the lowest administrative unit) in the Amhara region. Understanding the spatiotemporal distribution of malaria is essential for targeting appropriate parasite clearance interventions to achieve the elimination goal. However, little is known about the spatiotemporal distribution of malaria incidence in the intervention and non-intervention areas. This study aimed to investigate the spatiotemporal distribution of community-based malaria in the intervention and non-intervention kebeles between 2013 and 2018 in the Amhara Regional State, Ethiopia.
METHODS: Malaria data from 212 kebeles in eight districts were downloaded from the District Health Information System2 (DHIS2) database. We used Autoregressive integrated moving average (ARIMA) model to investigate seasonal variations; Anselin Local Moran's I statistical analysis to detect hotspot and cold spot clusters of malaria cases; and a discrete Poisson model using Kulldorff scan statistics to identify statistically significant clusters of malaria cases.
RESULTS: The result showed that the reduction in the trend of malaria incidence was higher in the intervention areas compared to the non-intervention areas during the study period with a slope of -0.044 (-0.064, -0.023) and -0.038 (-0.051, -0.024), respectively. However, the difference was not statistically significant. The Global Moran's I statistics detected the presence of malaria clusters (z-score = 12.05; p<0.001); the Anselin Local Moran's I statistics identified hotspot malaria clusters at 21 locations in Gendawuha and Metema districts. A statistically significant spatial, temporal, and space-time cluster of malaria cases were detected. Most likely type of spatial clusters of malaria cases (LLR = 195501.5; p <0.001) were detected in all kebeles of Gendawuha and Metema districts. The temporal scan statistic identified three peak periods between September 2013 and November 2015 (LLR = 8727.5; p<0.001). Statistically significant most-likely type of space-time clusters of malaria cases (LLR = 97494.3; p<0.001) were detected at 22 locations from June 2014 to November 2016 in Metema district.
CONCLUSION: There was a significant decline in malaria incidence in the intervention areas. There were statistically significant spatiotemporal variations of malaria in the study areas. Applying appropriate parasite clearance interventions is highly recommended for the better achievement of the elimination goal. A more rigorous evaluation of the impact of parasite clearance interventions is recommended.

DOI: https://doi.org/10.1371/journal.pone.0274500
J Vector Borne Dis. 2022 Apr-Jun;59(2):59(2): 109-114

An overview of dengue viral infection circulating in Pakistan.

Liaqat Ali, Zakkia Gul, Asiya Ijaz, Nouman Khalid, Falak Zeb, Samia Afzal, Anayat Ullah, Fazli Subhan, Saeed Ahmed.

   BACKGROUND & OBJECTIVES: Dengue virus (DENV) is an RNA virus that infects approximately 2.5 billion people around the world. The incidence of dengue fever has rapidly increased at an alarming rate in the last few years and has affected thousands of people in Pakistan. This review explores the prevalence, serotypes and pathogenesis of dengue virus circulating in Pakistan.
METHODS: A systematic review of observational studies published between 1994 and December 2019 was performed. All records of the confirmed outbreak of dengue fever in Pakistan were reviewed and articles containing no primary data were excluded.
RESULTS: Four identified serotypes of dengue virus (DENV 1-4) circulate in different regions of the world causing epidemics. The most prevalent serotype, which is still epidemic and dominant in Pakistan, is DENV-2. Many factors like over-population, rapid urbanization, travelling, lack of vector control in dengue endemic areas and inadequate health-care are responsible of dynamic and huge raise of dengue in Pakistan.
INTERPRETATION & CONCLUSION: Currently there is no specific treatment for prevention of dengue virus. Recently some antiviral compounds were being tested to eradicate this disease. There is a need to develop an efficient and safe vaccine for all four serotypes to combat dengue viral infection globally and particularly in Pakistan.

Keywords:  Dengue virus; Non-structural proteins; Pathogenesis; Prevalence; Serotypes

DOI:  https://doi.org/10.4103/0972-9062.331412