Urban Ecology of Arboviral Mosquito Vectors Along the Kenyan Coast

Abstract The purpose of this study was to determine the ecology of the common arboviral mosquito vectors in Mombasa, Kilifi and Malindi urban areas of coastal Kenya. Mosquito larvae were collected using standard dippers and pipettes. Egg survivorship in dry soil was evaluated by collecting soil samples from dry potential larval developmental sites, re-hydrating them for hatching and rearing of the eventual larvae to adults. Adult mosquitoes were collected with CDC light traps and BG-Sentinel traps. All blood-fed females were tested for bloodmeal origin. Mosquitoes were screened for arboviruses using RT-qPCR. Overall, the predominant species were Culex quinquefasciatus (Say) 72.4% (n = 2,364) and Aedes aegypti (L.), 25.7%, (n = 838). A total of 415 larval developmental sites were identified indoors (n = 317) and outdoors (n = 98). The most productive larval developmental sites, both indoors and outdoors, were assorted small containers, water tanks, drainages, drums, and jerricans. Overall, 62% (n = 18) of the soil samples collected were positive for larvae which were used as a proxy to measure the presence of eggs. The mosquitoes fed on humans (29.8%) and chickens (3.7%). Of 259 mosquitoes tested for viral infection, 11.6% were positive for Flavivirus only. The most productive larval developmental sites for arboviral vectors indoors were small containers, water tanks, jerricans, and drums whereas small containers, water tanks, drainage channels, buckets, tires, and water troughs were the productive larval developmental sites outdoors.

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Assessment of Geologic Controls of Flooding in Parts of OBIO/AKPOR L.G.A., Rivers State, Nigeria

Journal of Geological Research ◽

10.30564/jgr.v3i2.2902 ◽

2021 ◽

Vol 3 (2) ◽

Author(s):

Eruebi Toju B ◽

Eze Uchechukwu Stanley ◽

Ibitoye Taiwo Abel ◽

Abolarin Olayiwola Macpaul

Keyword(s):

Hydraulic Conductivity ◽

Specific Gravity ◽

Bulk Density ◽

Urban Areas ◽

Drainage System ◽

Soil Samples ◽

Laboratory Analysis ◽

Drainage Channels ◽

Rivers State ◽

Flooded Areas

Flooding of Municipal areas is a frequent environmental occurrence in Rivers State that occurs when rainfall runoff meets land surfaces with low water absorbing capacity or when it overwhelms drainage channels. In order to assess the flood situation in the study area, an integrated method which involves Field-measurement, Geographic information system (GIS), Laboratory analysis of soil samples and topographic studies were employed. Digital Elevation Model of the study area reveals that the flooded areas are situated in areas with elevations lower than its surrounding, thereby acting as a natural basin to retain flood waters after rainfall. Four holes were drilled to depth of 3m to obtain soil samples at 1 m sampling interval, from which laboratory analysis was carried out to determine some geotechnical parameters such as soil’s particle size, specific gravity, bulk density, porosity, moisture content, permeability and hydraulic conductivity. Results from the analysis show that permeability, hydraulic conductivity and porosity diminishes with respect to depth. The soil in the flooded areas have high fines content (silt and clay), high bulk density which increase with depth and a specific gravity that is typical of organic rich soils that contain sand mixed with a considerable amount of fines. At Nkpolu, mean permeability rates of 0.003cm/sec, 0.009cm/sec and 0.033cm/sec were obtained at 1, 2 and 3m respectively. At Eneka, mean permeability rates of 0.011cm/sec, 0.018cm/sec and 0.014cm/sec were obtained at 1, 2 and 3m respectively, while at Rukpokwu, mean Permeability rates of 0.021cm/sec was obtained at 1m, while 0.006cm/sec was obtained at 2 and 3m respectively. The Mean hydraulic conductivity for the locations under study is of the order of 10-4ft/day. This study has shown that the flooded areas are located in low lying urban areas which act as basins, therefore, the top soil is crusted with highly compacted soil horizons beneath. With high and frequent rainfall in the region which generates a lot of runoff, in addition to poor drainage system, flooding of the study area occurs frequently. Therefore, construction and maintenance of efficient drainage channels for an effective solution to urban pluvial flooding in the study area are thereby recommended.

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Urban ecology of arboviral mosquito vectors along the Kenyan coast

10.1101/593350 ◽

2019 ◽

Cited By ~ 1

Author(s):

Jonathan Karisa ◽

Simon Muriu ◽

Donwilliams Omuoyo ◽

Boniface Karia ◽

Doris Nyamwaya ◽

...

Keyword(s):

Urban Ecology ◽

Quantitative Polymerase Chain Reaction ◽

Hemorrhagic Fever ◽

Soil Samples ◽

Breeding Habitat ◽

Enzyme Linked Immunosorbent Assay ◽

Mosquito Vectors ◽

Habitat Types ◽

Valley Fever ◽

Coastal Kenya

ABSTRACTBackgroundThe emergence and re-emergence of arboviral infections particularly Chikungunya, dengue hemorrhagic fever, rift valley fever, and yellow fever in humans around the world threatens global health and security. The purpose of this study was to determine the urban ecology of the common arboviral mosquito vectors in urban Coastal Kenya areas.Materials and MethodsThe current study was conducted in urban settings of Kilifi and Mombasa counties in coastal Kenya in 2016 to 2017. Adult mosquitoes were collected both indoors and outdoors by CDC light traps and BG-Sentinel traps respectively. All blood fed mosquitoes were tested for blood meal sources by an Enzyme Linked Immunosorbent Assay (ELISA). Mosquito larvae were collected using standard dippers and pipettes. Egg survivorship in dry soil was evaluated by collecting of soil samples from dry potential breeding habitats, watering them for hatching and rearing of the eventual larvae to adults. Mosquitoes were screened forFlavivirus, Alphavirus,andPhlebovirusarboviruses using Reverse Transcriptase quantitative Polymerase Chain Reaction (RT qPCR).ResultsA total of 3,264 adult mosquitoes belonging to ten species ofCulex, AedesandAnopheleswere collected. Overall, the predominant species wereCx. quinquefasciatus72.4% (n=2,364) andAe. aegypti,25.7%, (n=838). A total of 415 breeding habitat types were identified indoors (n=317) and outdoors (n=98). The most productive habitat types in both indoors and outdoors were: assorted small containers, water tanks, drainages, drums and jericans. Overall, 62% (n=18) of the soil samples collected from the two sites (Kilifi and Malindi) were positive for larvae which were used as proxy to measure the presence of eggs. The mosquitoes had high preference for human blood (29.81%) and chicken (3.73%) but none had fed on either goat or bovine. Of 259 mosquitoes tested for viral infection, 11.6% were positive forflavivirusonly.ConclusionDomestic and peri-domestic containers were identified to be the key breeding areas of arboviral vectors. Therefore, efforts should be put in place targeting the productive habitat types.

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Urban ecology of arboviral mosquito vectors along the Kenyan coast

10.21203/rs.2.19427/v1 ◽

2019 ◽

Author(s):

Jonathan Karisa ◽

Simon Muriu ◽

Donwilliams Omuoyo ◽

Boniface Karia ◽

Moses Ngari ◽

...

Keyword(s):

Urban Ecology ◽

Quantitative Polymerase Chain Reaction ◽

Hemorrhagic Fever ◽

Soil Samples ◽

Breeding Habitat ◽

Enzyme Linked Immunosorbent Assay ◽

Mosquito Vectors ◽

Habitat Types ◽

Valley Fever ◽

Coastal Kenya

Abstract Background The emergence and re-emergence of arboviral infections particularly Chikungunya, dengue hemorrhagic fever, Rift Valley fever, and yellow fever in humans around the world threatens global health. The purpose of this study was to determine the urban ecology of the common arboviral mosquito vectors in urban Coastal Kenya areas.Materials and Methods The current study was conducted in urban settings of Kilifi and Mombasa counties in coastal Kenya in 2016 to 2017. Adult mosquitoes were collected both indoors and outdoors by CDC light traps and BG-Sentinel traps respectively. All blood fed mosquitoes were tested for blood meal sources by an Enzyme Linked Immunosorbent Assay (ELISA). Mosquito larvae were collected using standard dippers and pipettes. Egg survivorship in dry soil was evaluated by collecting of soil samples from dry potential breeding habitats, watering them for hatching and rearing of the eventual larvae to adults. Mosquitoes were screened for Flavivirus, Alphavirus and Phlebovirus arboviruses using Reverse Transcriptase Quantitative Polymerase Chain Reaction (RT qPCR).Results A total of 3,264 adult mosquitoes belonging to ten species of Culex (Cx.), Aedes (Ae) and Anopheles (An.) were collected. Overall, the predominant species were Cx. quinquefasciatus 72.4% (n=2,364) and Ae. aegypti, 25.7%, (n=838). A total of 415 breeding habitat types were identified indoors (n=317) and outdoors (n=98). The most productive habitat types in both indoors and outdoors were: assorted small containers, water tanks, drainages, drums and jericans. Overall, 62% (n=18) of the soil samples collected from the two sites (Kilifi and Malindi) were positive for larvae which were used as proxy to measure the presence of eggs. The mosquitoes had high preference for human blood (29.81%) and chicken (3.73%) but none had fed on either goat or bovine. Of 259 mosquitoes tested for viral infection, 11.6% were positive for Flavivirus only.Conclusion Peri-domestic containers were identified to be the key breeding areas of arboviral vectors.

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High Parasitic Contamination of Soil Samples in the North of Iran: a Potential Risk of Parasitic Infection for Tourists

Infectious Disorders - Drug Targets ◽

10.2174/1871526520666200602150446 ◽

2020 ◽

Vol 20 ◽

Author(s):

Beheshteh Haghparast-kenari ◽

Tooran Nayeri ◽

Shahabeddin Sarvi ◽

Mohammad Taghi Rahimi ◽

Ehsan Ahmadpour ◽

...

Keyword(s):

Contaminated Soil ◽

Urban Areas ◽

Intestinal Parasites ◽

Parasitic Infection ◽

Animal Husbandry ◽

Soil Samples ◽

Human Society ◽

Public Parks ◽

The North ◽

North Of Iran

Background: Soil-transmitted parasites (STPs) are significant intestinal parasites that infect humans and animals and impose considerable burdens on human society and animal husbandry industries. Therefore, the present study aimed to determine the prevalence of parasitic elements of soil samples collected from the north of Iran. Methods: A total of 256 soil samples were collected from public parks, public places, vegetable gardens, sand heaps, and shadow areas near houses in the north of Iran and examined using the sucrose flotation method. Results: Out of 256 examined samples, 131 (51.2%) ones showed parasitic contamination including larvae (43%), oocysts (14.1%), and different eggs (6.6%). According to the results, the most and least common parasites observed in the samples were larvae (43%), as well as Toxascaris leonina, and Trichuris trichiura (0.4%), respectively. Moreover, the most and least contaminated locations were sand heaps (62.5%) and shadow areas near houses (45.6%), respectively. Regarding cities, Behshahr (68.3%) and Sari (67.5%) had the highest contaminated soil samples, whereas Chalus (37.5%) showed the lowest contamination. On the other hand, rural samples showed more contamination, compared to urban areas (P< 0.05). Conclusion: The findings of the present study indicate that the overall prevalence of STPs in examined areas and highly contaminated soil samples can be considered as a potential source of human contamination particularly tourists with STPs.

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Diversity of organisms

10.1093/oso/9780198827238.003.0005 ◽

2018 ◽

Author(s):

Philip James

Keyword(s):

Life Cycle ◽

Urban Areas ◽

Native Species ◽

New Technologies ◽

Urban Environments ◽

Green Spaces ◽

The Common ◽

Living Organisms ◽

Micro Organisms ◽

Diversity Of Life

The focus of this chapter is an examination of the diversity of living organisms found within urban environments, both inside and outside buildings. The discussion commences with prions and viruses before moving on to consider micro-organisms, plants, and animals. Prions and viruses cause disease in plants and animals, including humans. Micro-organisms are ubiquitous and are found in great numbers throughout urban environments. New technologies are providing new insights into their diversity. Plants may be found inside buildings as well as in gardens and other green spaces. The final sections of the chapter offer a discussion of the diversity of animals that live in urban areas for part or all of their life cycle. Examples of the diversity of life in urban environments are presented throughout, including native and non-native species, those that are benign and deadly, and the common and the rare.

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Residues and Persistence of Glyphosate in Irrigation Water

Weed Science ◽

10.1017/s0043174500065395 ◽

1976 ◽

Vol 24 (1) ◽

pp. 47-50 ◽

Cited By ~ 12

Author(s):

R. D. Comes ◽

V. F. Bruns ◽

A. D. Kelley

Keyword(s):

Irrigation Water ◽

Soil Samples ◽

Single Site ◽

Application Site ◽

Canal Water ◽

Aminomethylphosphonic Acid ◽

Dry Soil

Neither glyphosate [N-(phosphonomethyl)glycine] nor the soil metabolite aminomethylphosphonic acid were detected in the first flow of water through two canals following application of glyphosate at 5.6 kg/ha to ditchbanks when the canals were dry. Soil samples collected the day before canals were filled (about 23 weeks after treatment) contained about 0.35 ppm glyphosate and 0.78 ppm aminomethylphosphonic acid in the 0 to 10-cm layer. When glyphosate was metered into the water at a rate calculated to provide 150 ppb in the canal water at a single site on two flowing canals, about 70% of the glyphosate was accounted for 1.6 km downstream from the application site. Thereafter, the rate of disappearance diminished, and about 58% of the applied glyphosate was present at the end of the canals 8 or 14.4 km downstream from the introduction sites.

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Marking Religious and Ethnic Boundaries: Cases from the Ancient Golan Heights

Church History ◽

10.2307/3169396 ◽

2000 ◽

Vol 69 (3) ◽

pp. 519-557 ◽

Cited By ~ 3

Author(s):

Robert C. Gregg

Keyword(s):

Rhode Island ◽

Religious Identity ◽

Urban Areas ◽

Religious Groups ◽

Small Communities ◽

Rural Settings ◽

The Common ◽

Late Roman Period ◽

Common Era

In the aftermath of the 1967 “Six Days' War,” 254 ancient inscribed stones were found in forty-four towns and villages of the Golan Heights—241 in Greek, 12 in Hebrew or Aramaic, and 1 in Latin. These stones, along with numerous architectural fragments, served as the basis of the 1996 book by myself and Dan Urman, Jews, Pagans, and Christians in the Golan Heights—a study of settlement patterns of people of the three religions in this region in the early centuries of the common era.1 The area of the Golan heights, roughly the size of Rhode Island, was in antiquity a place of agriculture and, for the most part, small communities. Though historians of religions in the late Roman period have long been aware of the “quartering” of cities, and of the locations of particular religious groups in this or that section of urban areas, we have had little information concerning the ways in which Hellenes, Jews, and Christians took up residence in relation to each other in those rural settings featuring numerous towns and hamlets— most presumably too small to have “zones” for ethnic and religious groups. The surviving artifacts of a number of the Golan sites gave the opportunity for a case study. Part 1 of this article centers on evidence for the locations and possible interactions of members of these religious groups in the Golan from the third to the seventh centuries and entails a summary of findings in the earlier work, while part 2 takes up several lingering questions about religious identity and ways of “marking” it within Golan countryside communities. Both sections can be placed under a rubric of “boundary drawing and religion.”

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Development of Resistance to Hymexazol Among Pythium Species in Cucumber Greenhouses in Oman

Plant Disease ◽

10.1094/pdis-11-16-1680-re ◽

2018 ◽

Vol 102 (1) ◽

pp. 202-208 ◽

Cited By ~ 8

Author(s):

Zainab M. Al-Balushi ◽

Hesham Agrama ◽

Issa H. Al-Mahmooli ◽

Sajeewa S. N. Maharachchikumbura ◽

Abdullah M. Al-Sadi

Keyword(s):

Ribosomal Rna ◽

Management Strategies ◽

Soil Samples ◽

Integrated Disease Management ◽

Pythium Species ◽

Internal Transcribed Spacer Region ◽

Development Of Resistance ◽

The Common ◽

Cucumber Roots ◽

Further Development

A study was conducted to characterize the common Pythium spp. in greenhouses in Oman and their level of resistance to hymexazol, a widely used fungicide in the country. Pythium isolates were obtained from soil samples, cocopeat bags, and cucumber roots collected from seven regions in the country. Identification of 80 Pythium isolates to the species level using sequences of the internal transcribed spacer region of the ribosomal RNA showed that they belong to four species: Pythium aphanidermatum (77 isolates), P. spinosum (1 isolate), P. myriotylum (1 isolate), and P. catenulatum (1 isolate). Investigating the aggressiveness of three Pythium spp. on cucumber showed that P. aphanidermatum, P. myriotylum, and P. spinosum are pathogenic. Phylogenetic analysis of P. aphanidermatum isolates showed that most of the isolates obtained from cocopeat clustered separately from isolates obtained from soil and roots. This may indicate a difference in the origin of the cocopeat isolates. Evaluating the resistance of 27 P. aphanidermatum isolates to hymexazol showed that most isolates were sensitive (0.9 to 31.2 mg liter−1) whereas one isolate was resistant (142.9 mg liter−1). This study is the first to report P. myriotylum and P. catenulatum in Oman. It is also the first to report the development of resistance to hymexazol among P. aphanidermatum populations from greenhouses. Growers should use integrated disease management strategies to avoid further development of resistance to hymexazol.

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2 + 1 Highways: Overview and Future Directions

Advances in Civil Engineering ◽

10.1155/2018/2705716 ◽

2018 ◽

Vol 2018 ◽

pp. 1-13

Author(s):

Manuel Romana ◽

Marilo Martin-Gasulla ◽

Ana T. Moreno

Keyword(s):

Urban Areas ◽

High Performance ◽

White Paper ◽

Future Directions ◽

Research Directions ◽

Traffic Volumes ◽

Primary Means ◽

The Common ◽

Rural Access ◽

Transportation Research

Most of the rural transportation system is composed of two-lane highways, and many of them serve as the primary means for rural access to urban areas and freeways. In some highways, traffic volumes can be not high enough to justify a four-lane highway but higher than can be served by isolated passing lanes, or can present high number of head-on collisions. In those conditions, 2 + 1 highways are potentially applicable. This type of highway is used to provide high-performance highways as intermediate solution between the common two-lane highway and the freeway. Successful experiences reported in Germany, Sweden, Finland, Poland, or Texas (US) may suggest that they are potentially applicable in other countries. The objective of this white paper is to provide an overview of the past practice in 2 + 1 highways and discuss the research directions and challenges in this field, specially focusing on, but not limited to, operational research in association with the activities of the Subcommittee on Two-Lane Highways (AHB40 2.2) of the Transportation Research Board. The significance of this paper is twofold: (1) it provides wider coverage of past 2 + 1 highways design and evaluation, and (2) it discusses future directions of this field.

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