bims-mosdis 2022-05-22 papers

bims-mosdis

Biomed News

on Mosquito distribution and disease

Issue of 2022‒05‒22
twenty-six papers selected by
Richard Halfpenny
Staffordshire University

A Cross-Sectional Household Survey in the US Virgin Islands (2019) Reveals Cisterns as Challenging Peridomestic Aedes aegypti Habitats.
Landscape Composition Affects Elements of Metacommunity Structure for Culicidae Across South-Eastern Illinois.
Island biogeography and human practices drive ecological connectivity in mosquito species richness in the Lakshadweep Archipelago.
[Culicidae Larvae and Their Seasonal Dynamics in the Region of Fez-Meknes, Morocco].
Diurnal biting of malaria mosquitoes in the Central African Republic indicates residual transmission may be "out of control".
Updated spatio-temporal distribution of Aedes (Stegomyia) albopictus in Brazil.
Elimination of a closed population of the yellow fever mosquito, Aedes aegypti, through releases of self-limiting male mosquitoes.
Status of Vector Control Capabilities and Capacities in Florida and Texas, and its Potential Public Health Consequences.
Evidence for serial founder events during the colonization of North America by the yellow fever mosquito, Aedes aegypti.
Habitat-Specific Host Selection Patterns of Culex quinquefasciatus and Culex nigripalpus in Florida.
[Mosquitoes, Distribution and Specific Richness in Eight Countries of Africa: Cape Verde, Mauritania, Senegal, Gambia, Mali, Burkina Faso, Niger and Chad].
Functional aspects of evolution in a cluster of salivary protein genes from mosquitoes.
Asymptomatic school-aged children are important drivers of malaria transmission in a high endemicity setting in Uganda.
Spatial statistical and environmental correlation analyses on vector density, vector infection index and Japanese encephalitis cases at the village and pigsty levels in Liyi County, Shanxi Province, China.
Effect of the Rural and Urban Microclimate on Mosquito Richness and Abundance in Yucatan State, Mexico.
Greening Up For Mosquitoes: A Comparison of Green Stormwater Infrastructure in a Semiarid Region.
LOCAL KNOWLEDGE OF ADAPTIVE STRATEGIES AGAINST MALARIA ENDEMICITY IN THE OKAVANGO DELTA, BOTSWANA.
Climate Change and Cascading Risks from Infectious Disease.
Aedes japonicus japonicus in Nebraska and Texas.
Clusters of malaria cases at sub-district level in endemic area in Java Island, Indonesia.
A cost analysis of the diagnosis and treatment of malaria at public health facilities and communities in three districts in Rwanda.
Culex coronator: A New Species Record For Monroe County, Florida.
Ecological and seasonal variations and other factors associated with clinical malaria in the Central Region of Ghana: A cross-sectional study.
Assessment of electronic surveillance and knowledge, attitudes, and practice (KAP) survey toward imported malaria surveillance system acceptance in France.
Distance to public transit predicts spatial distribution of dengue virus incidence in Medellín, Colombia.
Could China's journey of malaria elimination extend to Africa?

J Am Mosq Control Assoc. 2022 Jun 01. 38(2): 113-117

A Cross-Sectional Household Survey in the US Virgin Islands (2019) Reveals Cisterns as Challenging Peridomestic Aedes aegypti Habitats.

Krystal R Seger, Corey A Day, Lee Gaeddert, Gouthami Rao, Amy Kahler, Esther M Ellis, Brett R Ellis, Brian D Byrd.

  Most residences in the United States Virgin Islands (USVI) rely on household rainwater-catchment systems and subterranean cisterns for long-term water storage that may provide suitable habitats for mosquitoes of public health relevance. We conducted a household cistern survey (n = 164) on the islands of St. Croix, St. John, and St. Thomas in 2019. The survey revealed that 45.7% (95% CI: 38.3-53.4%) of cisterns contained mosquitoes (adult and/or immature mosquitoes). Aedes aegypti, a vector of chikungunya, dengue, and Zika viruses in the USVI, was found in 27.4% (95% CI: 21.2-34.7%) of cisterns and accounted for 83.3% of the total mosquitoes identified in the study. The odds of detecting mosquitoes in a cistern were 5.45 times higher at locations where the residents reported that they had observed adult mosquitoes coming out of their cisterns (95% CI: 2.25-14.21), suggesting that vector control personnel should consider resident complaints about mosquitoes in their cistern as valid and likely reliable self-assessments. Resident mosquito management practices in cisterns did not correspond with decreased odds of mosquito detection. We conclude that cisterns in the USVI commonly provide habitat for immature and adult Ae. aegypti, which may decrease the effectiveness of area-wide mosquito control strategies. Additional studies are necessary to evaluate the importance of these cisterns as they relate to mosquito production and arbovirus transmission risk, and to assess physical and chemical control methods.

Keywords:  Management practices; St. Croix; St. John; St. Thomas; mosquito control; rainwater-catchment systems

DOI:  https://doi.org/10.2987/21-7022
Front Public Health. 2022 ;10 872812

Landscape Composition Affects Elements of Metacommunity Structure for Culicidae Across South-Eastern Illinois.

Valeria Trivellone, Yanghui Cao, Millon Blackshear, Chang-Hyun Kim, Christopher Stone.

  The interplay among invasive alien vectors and the species assemblage of native potential vectors in areas of range expansion may affect the dynamics of pathogen transmission. In this study we investigate how Aedes albopictus, an invasive mosquito of considerable public health concern fits within mosquito communities at the edge of its range of distribution. This was addressed using a 2-year field survey of mosquitoes in south-eastern Illinois. We found that Ae. albopictus was more broadly distributed in this region than previously realized, with new occurrence records for nine counties. Abundance of this species varied strongly and peaked in locations of low-intermediate overall mosquito species richness. This differed from overall mosquito abundance, as well as abundance of another important vector, Cx. pipiens, for which the abundance-richness relationships were best described with power functions. Metacommunity analyses revealed that mosquito communities showed a non-random distribution with a Clementsian gradient, which suggests a pattern whereby distinct species assemblages are associated with specific habitats or environmental conditions. Land use was a significant underlying factor shaping mosquito community structure and species assemblages. Multivariate analyses showed that while Ae. canadensis and Cx. pipiens complex mosquitoes were associated with high and low proportions of wetlands in the environment, respectively, Ae. albopictus was most strongly associated with urban settlements. This work sheds light on landscape-level processes, such as niche differentiation driven by urban and agricultural development, structuring mosquito communities. We suggest that mosquito community assessments across habitats be incorporated as part of a One Health vector surveillance approach to aid in the goal of prediction and prevention of new and (re-)emerging vector-borne diseases.

Keywords:  Aedes albopictus; Culicidae; biodiversity; land use; mosquito surveillance; species assemblage

DOI:  https://doi.org/10.3389/fpubh.2022.872812
Sci Rep. 2022 May 16. 12(1): 8060

Island biogeography and human practices drive ecological connectivity in mosquito species richness in the Lakshadweep Archipelago.

Muhammad Nihad P P, Rohini P D, Sutharsan G, Anagha Ajith P K, Sumitha M K, Shanmuga Priya A, Rahul P, Sasikumar V, Shaibal Dasgupta, Jayalakshmi Krishnan, Farah Ishtiaq.

Mosquitoes are globally distributed and adapted to a broad range of environmental conditions. As obligatory hosts of many infectious pathogens, mosquito abundance and distribution are primarily determined by the presence and quality of larval habitats. To understand the dynamics and productivity of larval habitats in changing island environments, we conducted a four-month mosquito survey across ten inhabited islands in the Lakshadweep archipelago. Using fine-resolution larval habitat mapping, we recorded 7890 mosquitoes representing 13 species and 7 genera. Of these, four species comprised 95% of the total collections-Aedes albopictus (Stegomyia) was the dominant species followed by Armigeres subalbatus, Culex quinquefasciatus and Malaya genurostris. We found larval species richness was positively associated with the island area and mosquito larval richness (Chao1 estimator) was higher in artificial habitats than in natural habitats. Furthermore, mosquito species composition did not deteriorate with distance between islands. Mosquito abundance by species was associated with microclimatic variables-pH and temperature. We detected co-existence of multiple species at a micro-habitat level with no evidence of interactions like competition or predation. Our study analyzed and identified the most productive larval habitats -discarded plastic container and plastic drums contributing to high larval indices predicting dengue epidemic across the Lakshadweep islands. Our data highlight the need to devise vector control strategies by removal of human-induced plastic pollution (household waste) which is a critical driver of disease risk.

DOI: https://doi.org/10.1038/s41598-022-11898-y
Med Trop Sante Int. 2021 Jun 30. pii: mtsibulletin.n1.2021.89. [Epub ahead of print]1(2):

[Culicidae Larvae and Their Seasonal Dynamics in the Region of Fez-Meknes, Morocco].

T Filali Mouatassem, A El Ouali Lalami, C Faraj, N Rais, R Guemmouh.

  Objective: As part of the prevention of vector-borne diseases in central Morocco, a study of the seasonal fluctuation of Culicidian biodiversity was conducted from November 2015 to November 2016 on four breeding sites located in the city of Fez in central Morocco (Jnan El Alami, Lgaâda dam, Awinat Elhajaj, Douwar Lhandiya Source). The study aimed to improve the knowledge of seasonal dynamics and activity period of Culicidian mosquitoes, in order to target the period of control.Methods: Larvae were collected by dipping method at a 15-day interval at least once a month. Statistical analyses were performed using version 3.6.1 of the statistical processing software.
Results: During this study, nine species were found with high monthly and seasonal variations in numbers of each species and from site to site. Predominant species are vectors of disease: Culex pipiens, Cx. perexiguus, Cx. theileri, known vectors of West Nile virus, followed by Anopheles maculipennis s. l. and An. sergentii that are the main vectors of malaria in Morocco. Cx. pipiens and Cx. perexiguus reached the highest density in September, while Cx. theileri was found in large numbers in February and can therefore emerge in late winter and mid-spring. The lowest number of An. sergentii was collected in November, but increased in September, October and December. An. maculipennis s. l. occurred in June, with recurrences in March and July. Culiseta longiareolata was found in spring and summer and in abundance in June. However, Uranotaenia unguiculata was only present in September and October. Both An. cinereus and Cx. hortensis were present in November and February.
Conclusion: The results obtained will be an important tool for management and monitoring Culicidae proliferation and can be used to improve the efficiency of control management.

Keywords:  An. maculipennis s. l.; An. sergentii; Anopheles cinereus; Awinat Elhajaj; Culex pipiens; Culicidian fauna; Culiseta longiareolata; Cx. hortensis; Cx. perexiguus; Cx. theileri; Douwar Lhandiya Source; Fez; Jnan EL Alami; Lgaâda dam; Maghreb; Morocco; Northern Africa; Seasonal fluctuation; Uranotaenia unguiculata

DOI:  https://doi.org/10.48327/mtsibulletin.n1.2021.89
Proc Natl Acad Sci U S A. 2022 May 24. 119(21): e2104282119

Diurnal biting of malaria mosquitoes in the Central African Republic indicates residual transmission may be "out of control".

Claire Sangbakembi-Ngounou, Carlo Costantini, Neil Michel Longo-Pendy, Carine Ngoagouni, Ousman Akone-Ella, Nil Rahola, Sylvie Cornelie, Pierre Kengne, Emmanuel Rivalyn Nakouné, Narcisse Patrice Komas, Diego Ayala.

  SignificanceTransmission of malarial parasites occurs via the bites of Anopheles mosquitoes, whose blood-feeding behavior modulates the risk of infection. In many malaria endemic regions, eradication strategies rely on reducing transmission by targeting nocturnal blood-feeding Anopheles with insecticidal nets. However, a proportion of mosquitoes may naturally feed when humans are not protected by nets, setting a ceiling to the efficacy of massive net-based interventions. In Bangui, Central African Republic, 20 to 30% of daily exposure to indoor bites occurs during daytime, and this fraction may correspond to mosquitoes escaping exposure to current vector control measures. Knowledge about the daily rhythmicity of mosquito biting is therefore crucial to adjust vector control tactics to protect people at places where they spend daytime.

Keywords:  Anopheles; Central African Republic; biting behavior; residual malaria; vector control

DOI:  https://doi.org/10.1073/pnas.2104282119
Acta Trop. 2022 May 11. pii: S0001-706X(22)00203-0. [Epub ahead of print] 106511

Updated spatio-temporal distribution of Aedes (Stegomyia) albopictus in Brazil.

Paula Fassicolo Variza, Camila Lorenz, Joice Guilherme de Oliveira, Millena Fernansdes, Sérgio Antonio Netto, Josiane Somariva Prophiro.

  Aedes albopictus is native to Asia and is ranked among the top 100 invasive species worldwide, with vector competence for dengue, Zika, and chikungunya viruses. Understanding Ae. albopictus dispersal is essential for effective monitoring and vector control strategies. In this study, we analysed and updated the distribution of Ae. albopictus in Brazil using data available from the Ministry of Health through the Rapid Index Survey for Aedes (LIRA) for the years 2015-2020. The results of this research were mapped to visually represent the current distribution of Ae. albopictus in Brazil. In 2015, the presence of the vector was confirmed in 271 of the 1,820 Brazilian municipalities sampled (14.9%), and in 2020 it was detected in 728 of the 2,937 municipalities sampled (24.8%). In 2020, all Brazilian states had recorded the presence of this critical vector with a broader geographic distribution in the Southeast and Midwest regions as compared to the North, Northeast, and South regions. It was possible to note some stabilization of dispersion of this species in the Brazilian territory. The record of Ae. albopictus distribution advanced in Brazilian states and municipalities from 2015 to 2020; it is suggested that surveys of this vector be conducted periodically in all Brazilian municipalities and authorities should developing control strategies for this species together with Ae. aegypti.

Keywords:  LIRA; control; dengue; epidemiology; mosquito; vector

DOI:  https://doi.org/10.1016/j.actatropica.2022.106511
PLoS Negl Trop Dis. 2022 May 16. 16(5): e0010315

Elimination of a closed population of the yellow fever mosquito, Aedes aegypti, through releases of self-limiting male mosquitoes.

Prabhakargouda B Patil, Shaibal Kumar Dasgupta, Kevin Gorman, Angela Pickl-Herk, Mirel Puinean, Andrew McKemey, Bharat Char, Usha B Zehr, Shirish R Barwale.

Establishment of novel mosquito control technologies such as the use of genetically engineered insects typically involves phased testing to generate robust data-sets that support its safe and effective use as a vector control tool. In this study, we demonstrate the ability of the transgenic self-limiting OX513A Aedes aegypti strain to suppress a wild type Ae. aegypti population in an outdoor containment facility in India. OX513A is a genetically engineered Ae. aegypti strain with a repressible dominant self-limiting gene. When male adult OX513A mate with wild female adults, a single copy of the self-limiting gene is inherited by all the progeny, leading to death of >95% of progeny during larval/pupal development. A wild-type population of Ae. aegypti was established and stabilized during a 14 week period in five paired field cage units, each consisting of control and treatment cages, followed by weekly releases of OX513A male adults to suppress the target population. The successive introductions of OX513A male adults led to a consistent decline in wild type numbers eventually resulting in the elimination of Ae. aegypti from all treated cages within 10 to 15 weeks of release. This study demonstrates that Ae. aegypti elimination may be a realistic and achievable target in relatively isolated environments.

DOI: https://doi.org/10.1371/journal.pntd.0010315
J Am Mosq Control Assoc. 2022 Jun 01. 38(2): 104-108

Status of Vector Control Capabilities and Capacities in Florida and Texas, and its Potential Public Health Consequences.

Steven T Peper, Rui-De Xue, Steven M Presley.

  It has been reported that roughly 80% of vector control organizations throughout the southern USA lack critical capabilities to properly address potential vector populations and vector-borne diseases within their jurisdictions. This study further investigated current vector control capabilities and capacity within the states of Florida and Texas. It was reported that only 26% of jurisdictions in Florida and 14% in Texas reported that they were "fully capable." Both states are among the top 4 states relative to the number of human cases of mosquito-borne diseases, and both states have had local transmission of Zika virus. Respondents from Florida indicated that 88% of jurisdictions have vector control capabilities to some degree, with 65% of those reporting they had sufficient capabilities. Respondents from Texas indicated that 89% of jurisdictions have vector control capabilities to some degree, with 67% of those reporting they had sufficient capabilities. As the prioritization of resource commitment for vector control capabilities varies throughout the USA, it is imperative that each state evaluates their specific needs and current capabilities and capacity to best ensure the public health needs of their constituents.

Keywords:  Florida; Texas; funding; mosquito surveillance; vector control; vector-borne diseases

DOI:  https://doi.org/10.2987/21-7053
Ecol Evol. 2022 May;12(5): e8896

Evidence for serial founder events during the colonization of North America by the yellow fever mosquito, Aedes aegypti.

Evlyn Pless, Jeffrey R Powell, Krystal R Seger, Brett Ellis, Andrea Gloria-Soria.

  The Aedes aegypti mosquito first invaded the Americas about 500 years ago and today is a widely distributed invasive species and the primary vector for viruses causing dengue, chikungunya, Zika, and yellow fever. Here, we test the hypothesis that the North American colonization by Ae. aegypti occurred via a series of founder events. We present findings on genetic diversity, structure, and demographic history using data from 70 Ae. aegypti populations in North America that were genotyped at 12 microsatellite loci and/or ~20,000 single nucleotide polymorphisms, the largest genetic study of the region to date. We find evidence consistent with colonization driven by serial founder effect (SFE), with Florida as the putative source for a series of westward invasions. This scenario was supported by (1) a decrease in the genetic diversity of Ae. aegypti populations moving west, (2) a correlation between pairwise genetic and geographic distances, and (3) demographic analysis based on allele frequencies. A few Ae. aegypti populations on the west coast do not follow the general trend, likely due to a recent and distinct invasion history. We argue that SFE provides a helpful albeit simplified model for the movement of Ae. aegypti across North America, with outlier populations warranting further investigation.

Keywords:  Aedes aegypti; Invasive species; North America; genetic structure; population genetics; serial founder effect

DOI:  https://doi.org/10.1002/ece3.8896
J Am Mosq Control Assoc. 2022 Jun 01. 38(2): 83-91

Habitat-Specific Host Selection Patterns of Culex quinquefasciatus and Culex nigripalpus in Florida.

Chip Hancock, Jeremy V Camp.

  Blood-engorged Culex quinquefasciatus and Cx. nigripalpus were collected from 140 locations throughout Sarasota County, FL, from 2017 to 2020 to determine local, habitat-specific, and seasonal variations in the host usage patterns of these 2 important arbovirus vectors. Mosquitoes were collected using light traps, gravid traps, and via aspiration of resting shelters. Host was determined from 920 samples using multiple polymerase chain reaction protocols that target mitochondrial sequences specific to mammals, birds, and reptiles. The data were analyzed to test for statistical associations between host class and season or with habitat categories (urban, suburban, and rural). Culex quinquefasciatus took significantly more blood meals from birds compared to mammals, though a seasonal shift to a higher ratio of mammalian host usage was observed in fall. There was a habitat-dependent pattern of host usage by Cx. nigripalpus, with significantly more mammalian hosts identified from mosquitoes captured in rural habitats and a similar ratio of mammalian and avian hosts in urban habitats. In general humans were used as hosts by Cx. nigripalpus less often compared to Cx. quinquefasciatus. In contrast to previous studies, Cx. nigripalpus utilized ectothermic hosts (mostly reptiles) at a much higher ratio and exhibited no apparent seasonal shift in host selection.

Keywords:   Culex ; habitat; host selection; mosquito vector; seasonal variation; urban

DOI:  https://doi.org/10.2987/21-7054
Med Trop Sante Int. 2021 Jun 30. pii: mtsibulletin.2021.109. [Epub ahead of print]1(2):

[Mosquitoes, Distribution and Specific Richness in Eight Countries of Africa: Cape Verde, Mauritania, Senegal, Gambia, Mali, Burkina Faso, Niger and Chad].

E H Ndiaye, A Ould Mohamed Salem Boukhary, M Diallo, D Diallo, R Labbo, P Boussès, G Le Goff, V Robert.

  Mosquitoes (Diptera, Culicidae) form a family of insects of considerable public health importance. Mention of their presence/absence was tackled in the literature and by specialized websites for eight African countries: Cape Verde, Mauritania, Senegal, Gambia, Mali, Burkina Faso, Niger and Chad. In total, 216 species have been recorded belonging to 13 genera: Anopheles (48 species), Aedeomyia (2), Aedes (62), Coquillettidia (6), Culex (54), Culiseta (1), Eretmapodites (7), Ficalbia (3), Lutzia (1), Mansonia (2), Mimomyia (7), Toxorhynchites (4) and Uranotaenia (19). The presence of these species in the study area is certain except for three species whose presence is doubtful. This specific richness represents 6% of the world's richness. The countries with the highest specific richness are Burkina Faso (162 species), Senegal (143) and Mali (110); the country with the lowest richness is Cape Verde (11). This richness is lower in the north in hyper-arid climate and higher in the south in sub-humid climate. Chad is the least well inventoried country. All species are considered native, with the exception of Ae. (Stegomyia ) albopictus (the Asian tiger mosquito) introduced in 2016 into Mali and possibly Ae. (Ochlerotatus ) caspius into Mauritania and Ae. (Stg. ) aegypti introduced into Nouakchott, Mauritania. This synthesis of the knowledge may be useful for vector control, public health, and future research.

Keywords:  Biodiversity; Burkina Faso; Cape Verde; Chad; Culicidae; Diptera; Gambia; Mali; Mauritania; NUTS1; Niger; Sahel; Senegal; Species; inventory; sub-Saharan Africa

DOI:  https://doi.org/10.48327/mtsibulletin.2021.109
Insect Biochem Mol Biol. 2022 May 12. pii: S0965-1748(22)00067-4. [Epub ahead of print]146 103785

Functional aspects of evolution in a cluster of salivary protein genes from mosquitoes.

Patricia H Alvarenga, Denis R Dias, Xueqing Xu, Ivo M B Francischetti, Apostolos G Gittis, Gabriela Arp, David N Garboczi, José M C Ribeiro, John F Andersen.

  The D7 proteins are highly expressed in the saliva of hematophagous Nematocera and bind biogenic amines and eicosanoid compounds produced by the host during blood feeding. These proteins are encoded by gene clusters expressing forms having one or two odorant-binding protein-like domains. Here we examine functional diversity within the D7 group in the genus Anopheles and make structural comparisons with D7 proteins from culicine mosquitoes in order to understand aspects of D7 functional evolution. Two domain long form (D7L) and one domain short form (D7S) proteins from anopheline and culicine mosquitoes were characterized to determine their ligand selectivity and binding pocket structures. We previously showed that a D7L protein from Anopheles stephensi, of the subgenus Cellia, could bind eicosanoids at a site in its N-terminal domain but could not bind biogenic amines in its C-terminal domain as does a D7L1 ortholog from the culicine species Aedes aegypti, raising the question of whether anopheline D7L proteins had lost their ability to bind biogenic amines. Here we find that D7L from anopheline species belonging to two other subgenera, Nyssorhynchus and Anopheles, can bind biogenic amines and have a structure much like the Ae. aegypti ortholog. The unusual D7L, D7L3, can also bind serotonin in the Cellia species An. gambiae. We also show through structural comparisons with culicine forms that the biogenic amine binding function of single domain D7S proteins in the genus Anopheles may have evolved through gene conversion of structurally similar proteins, which did not have biogenic amine binding capability. Collectively, the data indicate that D7L proteins had a biogenic amine and eicosanoid binding function in the common ancestor of anopheline and culicine mosquitoes, and that the D7S proteins may have acquired a biogenic amine binding function in anophelines through a gene conversion process.

Keywords:  Biogenic amine; D7 proteins; Eicosanoids; Evolution; Gene duplication; Hematophagy; Mosquito; Odorant-binding protein; Protein diversity; Saliva

DOI:  https://doi.org/10.1016/j.ibmb.2022.103785
J Infect Dis. 2022 May 17. pii: jiac169. [Epub ahead of print]

Asymptomatic school-aged children are important drivers of malaria transmission in a high endemicity setting in Uganda.

John Rek, Sara Lynn Blanken, Joseph Okoth, Daniel Ayo, Ismail Onyige, Eric Musasizi, Jordache Ramjith, Chiara Andolina, Kjerstin Lanke, Emmanuel Arinaitwe, Peter Olwoch, Katharine A Collins, Moses R Kamya, Grant Dorsey, Chris Drakeley, Sarah G Staedke, Teun Bousema, Melissa D Conrad.

  Achieving malaria elimination requires a better understanding of the transmissibility of human infections in different transmission settings. This study aimed to characterize the human infectious reservoir in a high endemicity setting in eastern Uganda, using gametocyte quantification and mosquito feeding assays. In asymptomatic infections, gametocyte densities were positively associated with the proportion of infected mosquitoes (β=1.60, 95%CI 1.32-1.92, p < 0.0001). Combining transmissibility and abundance in the population, symptomatic and asymptomatic infections were estimated to contribute to 5.3% and 94.7% of the infectious reservoir, respectively. School-aged children (5-15 years-old) contributed to 50.4% of transmission events and were important drivers of malaria transmission.

Keywords:   Plasmodium falciparum ; Malaria transmission; Uganda; gametocytes; mosquito feeding assays

DOI:  https://doi.org/10.1093/infdis/jiac169
Parasit Vectors. 2022 May 19. 15(1): 171

Spatial statistical and environmental correlation analyses on vector density, vector infection index and Japanese encephalitis cases at the village and pigsty levels in Liyi County, Shanxi Province, China.

Mei-De Liu, Chun-Xiao Li, Jing-Xia Cheng, Tong-Yan Zhao.

  BACKGROUND: In the eco-epidemiological context of Japanese encephalitis (JE), geo-environmental features influence the spatial spread of the vector (Culex tritaeniorhynchus, Giles 1901) density, vector infection, and JE cases.METHODS: In Liyi County, Shanxi Province, China, the spatial autocorrelation of mosquito vector density, vector infection indices, and JE cases were investigated at the pigsty and village scales. The map and Enhanced Thematic Mapper (ETM) remote sensing databases on township JE cases and geo-environmental features were combined in a Geographic Information System (GIS), and the connections among these variables were analyzed with regression and spatial analyses.
RESULTS: At the pigsty level, the vector density but not the infection index of the vector was spatially autocorrelated. For the pigsty vector density, the cotton field area was positively related, whereas the road length and the distance between pigsties and gullies were negatively related. In addition, the vector infection index was correlated with the pigsty vector density (PVD) and the number of pigs. At the village level, the vector density, vector infection index, and number of JE cases were not spatially autocorrelated. In the study area, the geo-environmental features, vector density, vector infection index, and JE case number comprised the Geo-Environment-Vector-JE (GEVJ) intercorrelation net system. In this system, pig abundance and cotton area were positive factors influencing the vector density first. Second, the infection index was primarily influenced by the vector density. Lastly, the JE case number was determined by the vector infection index and the wheat area.
CONCLUSIONS: This study provided quantitative associations among geo-environmental features, vectors, and the incidence of JE in study sties, one typical northern Chinese JE epidemiological area without rice cultivation. The results highlighted the importance of using a diverse range of environmental management methods to control mosquito disease vectors and provided useful information for improving the control of vector mosquitoes and reducing the incidence of JE in the northern Chinese agricultural context.

Keywords:  Environment; Japanese encephalitis; Mosquito vector; Pigsty; Spatial analysis

DOI:  https://doi.org/10.1186/s13071-022-05305-8
Vector Borne Zoonotic Dis. 2022 May;22(5): 281-288

Effect of the Rural and Urban Microclimate on Mosquito Richness and Abundance in Yucatan State, Mexico.

Suemy Flores Ruiz, Salomé Cabrera Romo, Alfredo Castillo Vera, Ariane Dor.

  The objective of this study was to analyze the effect of the rural and urban microclimate on the presence of mosquitoes. Temperature (T) and relative humidity (RH; indoors and outdoors), as well as mosquito richness and abundance were measured in two sites (urban and rural) of the Yucatan State, Mexico. Species richness was higher in the urban site, whereas mosquito abundance was higher in the rural site. The microclimates of urban and rural housing differently affect mosquito richness and abundance. Mosquito richness and abundance were higher outdoors than indoors in the urban site, but they were higher indoors than outdoors in the rural site. For the urban site, analysis of the relation of T and RH with the registered parameters revealed that species richness increased with increasing indoor RH, and that mosquito abundance increased with increasing indoor T and RH. In the rural site, species richness was not affected, but abundance increased with increasing T and RH (indoors as well as outdoors). Results are discussed in the context of the management of mosquito transmitted diseases. No IRB approval was necessary since no ethical implications were identified to be reviewed by the ethical committee for the research of the ECOSUR Institution.

Keywords:  indoors and outdoors; mosquito community; relative humidity; temperature

DOI:  https://doi.org/10.1089/vbz.2021.0105
J Am Mosq Control Assoc. 2022 Jun 01. 38(2): 109-112

Greening Up For Mosquitoes: A Comparison of Green Stormwater Infrastructure in a Semiarid Region.

Heidi E Brown, Ladd Keith, Valerie Madera-Garcia, Anissa Taylor, Nicholas Ramirez, Irene Ogata.

  Green stormwater infrastructure provides environmental, economic, and health benefits as a strategy for building resilience against climate change impacts. However, it may inadvertently increase vulnerability due to improper design and construction or lack of maintenance. We engaged city stakeholders and a diverse student group to investigate possible maladaptation. After rain events, student interns collected data at green stormwater infrastructure, identified in partnership with city stakeholders, for both water retention and mosquito larvae, if present. During the sampling period in 2018, 24 rain events occurred, with 28 sites visited 212 times including visits to basins (63%), curb cuts (34%), and a bioswale (2%). The largest basin consistently retained water (mean: 3.3 days, SD: 2.3 days) and was a positive site for Culex quinquefasciatus, a West Nile virus vector. We found that while basins can become mosquito breeding habitat, there was no evidence that curb cuts were collecting and retaining water long enough. As cities turn to green stormwater infrastructure to address climate change impacts of increasing drought, flooding, and extreme heat, these findings can help in the selection of appropriate infrastructure design typologies.

Keywords:  Climate adaptation; West Nile virus; green stormwater infrastructure; maladaptation; resilience

DOI:  https://doi.org/10.2987/21-7055
Afr J Infect Dis. 2022 ;16(2): 21-34

LOCAL KNOWLEDGE OF ADAPTIVE STRATEGIES AGAINST MALARIA ENDEMICITY IN THE OKAVANGO DELTA, BOTSWANA.

Maphane Dirontsho, Ngwenya Barbara Ntombi, Kolawole Oluwatoyin Dare, Motsholapheko Moseki Ronald, Pagiwa Vincent.

  Background: An increasing recognition of the need to eliminate malaria infection globally and particularly in Africa where more than 90% of the cases originate, should enhance community awareness and participation in the same. The perennial freshwater of Okavango Delta located in northern Botswana, which is a source of rural livelihoods and a suitable habitat for the malaria-causing mosquito, and where malaria is endemic provides a suitable environment for the study. Therefore, local households' adaptive strategies against malaria transmission in the Okavango Delta were investigated.Materials and Methods: The data used in this paper is a subset or retrospective cohort of 79 households that reported malaria cases/incidences during the first community level household survey conducted from October-November 2015 on 355 households in Shakawe and Ngarange. The households were selected through stratified random sampling in the two study villages. The retrospective cohort household survey was conducted from 7-19 August 2016, in the two study sites. Data were collected through socio-economic survey, key informants' interviews and focus group discussions.
Results: The results obtained indicate that most cohort households embraced several adaptive strategies against malaria transmission. These included, inter alia, knowledge capacity building through attendance of health information and education workshops (69%), modifications of houses structures (49.4%), timing of activities and restricting movement at certain times of the day (43%).
Discussion: Although most of the stated adaptive strategies such as house screening were not exclusively aimed towards malaria prevention and adaptation, they nonetheless had postive spill over effect that could be a catalyst for eliminating malaria in the study area.

Keywords:  Botswana; Okavango Delta; adaptation; local knowledge; malaria control

DOI:  https://doi.org/10.21010/Ajid.v16i2.3
Infect Dis Ther. 2022 May 19.

Climate Change and Cascading Risks from Infectious Disease.

Jan C Semenza, Joacim Rocklöv, Kristie L Ebi.

  Climate change is adversely affecting the burden of infectious disease throughout the world, which is a health security threat. Climate-sensitive infectious disease includes vector-borne diseases such as malaria, whose transmission potential is expected to increase because of enhanced climatic suitability for the mosquito vector in Asia, sub-Saharan Africa, and South America. Climatic suitability for the mosquitoes that can carry dengue, Zika, and chikungunya is also likely to increase, facilitating further increases in the geographic range and longer transmission seasons, and raising concern for expansion of these diseases into temperate zones, particularly under higher greenhouse gas emission scenarios. Early spring temperatures in 2018 seem to have contributed to the early onset and extensive West Nile virus outbreak in Europe, a pathogen expected to expand further beyond its current distribution, due to a warming climate. As for tick-borne diseases, climate change is projected to continue to contribute to the spread of Lyme disease and tick-borne encephalitis, particularly in North America and Europe. Schistosomiasis is a water-borne disease and public health concern in Africa, Latin America, the Middle East, and Southeast Asia; climate change is anticipated to change its distribution, with both expansions and contractions expected. Other water-borne diseases that cause diarrheal diseases have declined significantly over the last decades owing to socioeconomic development and public health measures but changes in climate can reverse some of these positive developments. Weather and climate events, population movement, land use changes, urbanization, global trade, and other drivers can catalyze a succession of secondary events that can lead to a range of health impacts, including infectious disease outbreaks. These cascading risk pathways of causally connected events can result in large-scale outbreaks and affect society at large. We review climatic and other cascading drivers of infectious disease with projections under different climate change scenarios. Supplementary file1 (MP4 328467 KB).

Keywords:  Cascading risks; Chikungunya; Climate change; Dengue; Exposure; Hazard; Infectious diseases; Lyme disease; Malaria; Vulnerability

DOI:  https://doi.org/10.1007/s40121-022-00647-3
J Am Mosq Control Assoc. 2022 Jun 01. 38(2): 92-95

Aedes japonicus japonicus in Nebraska and Texas.

William J Sames, Jeff Hamik, James G Mann, Joshua D Bast, R Jason Pitts.

  Aedes japonicus japonicus continues to spread westward and in this study, its presence is documented in 8 counties in Nebraska and in Bowie County, TX. In 1998, Ae. japonicus was collected in Connecticut, New Jersey, and New York for the 1st records of this species in North America. Except for Louisiana, it has been reported from all states that border or are east of the Mississippi River. In Canada, it has been reported in Ontario and all eastern provinces. In the Pacific Northwest, it has been reported in Washington, Oregon, and British Columbia, and in the midwestern states that do not border the Mississippi River, Kansas, Oklahoma, and South Dakota are the only states to have reported its presence in peer-reviewed journals.

Keywords:  Culicidae; habitat; mosquito; new records; surveillance

DOI:  https://doi.org/10.2987/21-7048
Geospat Health. 2022 May 18. 17(1):

Clusters of malaria cases at sub-district level in endemic area in Java Island, Indonesia.

Dwi Sarwani Sri Rejeki, Sri Nurlaela, Devi Octaviana, Bangun Wijayanto, Solikhah Solikhah.

Malaria remains one of the essential public health problems in Indonesia. The year 2015 was originally set as the elimination target in Java Island, but there are still several regencies on Java reporting malaria cases. Spatial technology helps determine local variations in malaria transmission, control risk areas and assess the outcome of interventions. Information on distribution patterns of malaria at the sub-district level, presented as spatial, temporal, and spatiotemporal data, is vital in planning control interventions. Information on malaria transmission at the sub-district level in three regencies in Java (Banyumas, Kebumen, and Purbalingga) was collected from the Agency for Regional Development (Bappeda), the Population and Civil Registration Agency (Disdukcapil) and Statistics Indonesia (BPS). Global spatial autocorrelation and space-time clustering was investigated together with purely spatial and purely temporal analyses using geographical information systems (GIS) by ArcGis 10.2 and SaTScan 8.0 to detect areas at high risk of malaria. Our results show that malaria was spatially clustered in the study area in central Java, in particular in the Banyumas and Purbalingga regencies. The temporal analysis revealed that malaria clusters predominantly appeared in the period January-April. The results of the spatiotemporal analysis showed that there was one most likely malaria cluster and three secondary clusters in southern central Java. The most likely cluster was located in Purbalingga Regency covering one sub-district and remaining from the beginning of 2016 to the end of 2018. The approach used can assist the setting of resource priorities to control and eliminate malaria.

DOI: https://doi.org/10.4081/gh.2022.1048
Malar J. 2022 May 15. 21(1): 150

A cost analysis of the diagnosis and treatment of malaria at public health facilities and communities in three districts in Rwanda.

Ornella Masimbi, Janna M Schurer, Ellen Rafferty, Jean D' Amour Ndahimana, J Hellen Amuguni.

  BACKGROUND: Malaria is a potentially fatal disease spread by the bites of Plasmodium-infected Anopheles mosquitoes. Despite long-term efforts to control malaria in Rwanda, malaria incidence increased from 48 to 403 cases/1000 individuals between 2012 and 2016. The diagnosis and treatment of malaria occurs at multiple levels, but the costs of these activities are not well understood. This research was conducted to estimate the direct medical costs incurred by the Ministry of Health in diagnosing and treating malaria in three districts of Rwanda in 2018.METHODS: A cross-sectional and retrospective costing analysis was conducted in three districts that represented low (5-200 cases per 1000 individuals), moderate (> 200-400 cases per 1000 individuals), and high (> 400 cases per 1000 individuals) endemicity regions. Data on malaria cases managed at three healthcare levels (community, health centre, district hospital) was obtained from national databases. The direct medical costs of cases per malaria severity ('simple malaria', 'simple malaria with minor digestive symptoms', and 'severe malaria') were calculated based on the minimum package of health services provided. Total costs for each of the three districts were also calculated.
RESULTS: A total of 298,381 malaria cases were recorded in Burera, Kirehe, and Southern Kayonza districts in 2018. The average unit cost per case ranged from USD 1.36 (for simple malaria at the community level) to USD 92.80 (for severe malaria with cerebral complications at district hospitals). Simple malaria cases managed at health centres and district hospitals were more than two-fold (USD 2.99-USD 3.00) and more than eight-fold (USD 12.10-USD 12.12) higher, respectively, than those managed in the community (USD 1.36). Overall, the Ministry of Health incurred USD 645,647.68 in direct medical costs related to malaria management across the three districts in 2018. Changes in disease rates from different endemicity regions and costs of anti-malarial oral medications significantly impacted the study results.
CONCLUSION: In Rwanda, severe malaria results in much higher expenses compared to other malaria types. Prompt diagnosis and appropriate treatment are crucial to prevent the progression of simple malaria to severe malaria, to reduce Ministry of Health malaria expenditures, and to reduce community transmission.

Keywords:  Community Health Workers; Healthcare costs; Home-Based Management; Malaria; Rwanda

DOI:  https://doi.org/10.1186/s12936-022-04158-x
J Am Mosq Control Assoc. 2022 Jun 01. 38(2): 96-98

Culex coronator: A New Species Record For Monroe County, Florida.

Michael B Boehmler.

  Reported here are the first documented records of Culex coronator in Monroe County, FL. Adult female specimens were collected over several weeks on multiple islands, indicating that this species is established in all counties of the state of Florida. Global Positioning System coordinates and habitat descriptions are provided.

Keywords:   Culex coronator ; County record; Florida Keys; Monroe County

DOI:  https://doi.org/10.2987/21-7045
J Infect Public Health. 2022 May 04. pii: S1876-0341(22)00100-9. [Epub ahead of print]15(6): 631-637

Ecological and seasonal variations and other factors associated with clinical malaria in the Central Region of Ghana: A cross-sectional study.

Mavis Puopelle Dakorah, Enoch Aninagyei, Juliana Attoh, David Adedia, Clement Okraku Tettey, Isaac Kyei-Barffour, Desmond Omane Acheampong.

  BACKGROUND: This study investigated malaria transmission under various contrasting settings in the Central Region, a malaria endemic region in Ghana.METHODS: This cross-sectional study was carried out in five randomly selected districts in the Central Region of Ghana. Three of the districts were forested, while the rest was coastal. Study participants were selected to coincide with either the regular rainy or dry season. From each study site, hospital attendees were randomly selected with prior consent. Consciously, study participants were selected in both rainy (September and October, 2020) and dry (November and December, 2020) seasons. Clinical data for each patient was checked for clinical malaria suspicion and microscopic confirmation of malaria. Using SPSS Version 24 (Chicago, IL, USA), bivariate analysis was done to determine the association of independent variables (ecological and seasonal variations) with malaria status. When the overall analysis did not yield significant association, further statistical analysis was performed after stratification of variables (into age and gender) to determine whether any or both of them would significantly associate with the dependent variable.
RESULTS: Of the 3993 study participants, 62.5% were suspected of malaria whereas 38.2% were confirmed to have clinical falciparum malaria. Data analysis revealed that in both rainy and dry seasons, malaria cases were significantly higher in forested districts ) than coastal districts (x2 = 217.9 vs x2 = 50.9; p < 0.001). Taken together, the risk of malaria was significantly higher in the dry season (COR = 1.471, p < 0.001) and lower in coastal zones (COR = 0.826, p = 0.007). There was significant reduced risk of participants aged over 39 years of malaria (COR=0.657, p < 0.001). Whereas, in general patients between 10 and 19 years were insignificantly less likely to have malaria (COR = 0.911, p = 0.518) compared to participants aged less than< 10 years, the reverse was observed in coastal districts where patients less than 10 years of age in coastal districts were less likely to have malaria (COR=2.440, p = 0.003). In general, gender did not associate with malaria, but when stratified by study district, the risk of female gender to malaria was significantly higher in Agona Swedru (COR = 5.605, p < 0.001), Assin central (COR = 2.172, p < 0.001), Awutu Senya (COR = 2.410, p < 0.001) and Cape Coast (COR = 3.939, p < 0.001) compared to Abura-Asebu-Kwamankese.
CONCLUSION: This study demonstrated that the predictors of malaria differ from one endemic area to another. Therefore, malaria control interventions such as distribution of long-lasting insecticide treated bed nets, residual spraying with insecticide and mass distribution of antimalaria prophylaxis must be intensified in forested districts in all seasons with particular attention on females.

Keywords:  Central Region; Coastal; Ecological; Forest; Ghana; Malaria; Seasonal malaria

DOI:  https://doi.org/10.1016/j.jiph.2022.04.014
JAMIA Open. 2022 Apr;5(1): ooac012

Assessment of electronic surveillance and knowledge, attitudes, and practice (KAP) survey toward imported malaria surveillance system acceptance in France.

French Imported Malaria Study Group

  Objective: An electronic surveillance system was released to monitor morbidity and mortality incidence of imported malaria cases, investigate autochthonous cases, and assess chemosensitivity of Plasmodium isolates among travelers to and from endemic areas. The aim of this study is to evaluate the use of an electronic surveillance system for imported malaria in France.Materials and Methods: Three main indicators were used to assess the online malaria web-based surveillance system: (1) the quality of the surveillance system; (2) the capacity of the online system to early warning in case of particular events of public health; (3) the knowledge, attitude, and practice of online electronic system by practitioners of malaria network in France.
Results: Overall, the median time onset a case is reported to the system decrease by 99%, ranging from 227 days (144-309) to 2 days (1-6) in 2006 and 2020, respectively.
Conclusion: The online malaria surveillance system in France has demonstrated its effectiveness and can therefore be extended to carry out numerous investigations linked to research on malaria.

Keywords:  KAP survey; imported malaria; public health; surveillance system; travelers; web-based

DOI:  https://doi.org/10.1093/jamiaopen/ooac012
Sci Rep. 2022 May 18. 12(1): 8333

Distance to public transit predicts spatial distribution of dengue virus incidence in Medellín, Colombia.

Talya Shragai, Juliana Pérez-Pérez, Marcela Del Pilar Quimbayo-Forero, Raúl Rojo, Laura C Harrington, Guillermo Rúa-Uribe.

Dengue is a growing global threat in some of the world's most rapidly growing landscapes. Research shows that urbanization and human movement affect the spatial dynamics and magnitude of dengue outbreaks; however, precise effects of urban growth on dengue are not well understood because of a lack of sufficiently fine-scaled data. We analyzed nine years of address-level dengue case data in Medellin, Colombia during a period of public transit expansion. We correlate changes in the spread and magnitude of localized outbreaks to changes in accessibility and usage of public transit. Locations closer to and with a greater utilization of public transit had greater dengue incidence. This relationship was modulated by socioeconomic status; lower socioeconomic status locations experienced stronger effects of public transit accessibility and usage on dengue incidence. Public transit is a vital urban resource, particularly among low socioeconomic populations. These results highlight the importance of public health services concurrent with urban growth.

DOI: https://doi.org/10.1038/s41598-022-12115-6
Infect Dis Poverty. 2022 May 16. 11(1): 55

Could China's journey of malaria elimination extend to Africa?

Duoquan Wang, Shan Lv, Wei Ding, Shenning Lu, Hongwei Zhang, Kokouvi Kassegne, Shang Xia, Lei Duan, Xuejiao Ma, Lulu Huang, Roly Gosling, Joshua Levens, Salim Abdulla, Mutinta Mudenda, Moses Okpeku, Kenneth Kamwi Matengu, Potiandi Serge Diagbouga, Ning Xiao, Xiao-Nong Zhou.

  World Health Organization (WHO) certified China malaria-free on June 30, 2021, which brightens the goal of global malaria elimination efforts. China contributed its unique innovations to the global community: Artemisinin, discovered by Tu Youyou, has saved millions of lives globally; the "1-3-7" norm developed in 2012, has been adapted in the local contexts of countries in the Southeast Asia and Africa. How to the targets of Global Technical Strategy for Malaria (GTS) 2016-2030. By looking into the malaria control phase, towards elimination phase from 1960 to 2011 in sub-Saharan Africa and China, we found that the gap in malaria burden will widen unless the interventions in Africa are enhanced. It is imperative to identify the key China-Africa cooperation areas on malaria control and elimination, so that synergized efforts could be pooled together to help African countries achieve the elimination goal. The practices from China malaria control and elimination efforts could be leveraged to fast-track malaria elimination efforts in Africa, which makes it possible that the China's journey of malaria elimination extends to Africa.

Keywords:  Africa; China; Efforts; Elimination; Extend; Malaria

DOI:  https://doi.org/10.1186/s40249-022-00978-w