scholarly journals A laboratory-based study to explore the use of honey-impregnated cards to detect chikungunya virus in mosquito saliva

PLoS ONE ◽  
2021 ◽  
Vol 16 (4) ◽  
pp. e0249471
Author(s):  
Lisa Fourniol ◽  
Yoann Madec ◽  
Laurence Mousson ◽  
Marie Vazeille ◽  
Anna-Bella Failloux

Mosquito control is implemented when arboviruses are detected in patients or in field-collected mosquitoes. However, mass screening of mosquitoes is usually laborious and expensive, requiring specialized expertise and equipment. Detection of virus in mosquito saliva using honey-impregnated filter papers seems to be a promising method as it is non-destructive and allows monitoring the viral excretion dynamics over time from the same mosquito. Here we test the use of filter papers to detect chikungunya virus in mosquito saliva in laboratory conditions, before proposing this method in large-scale mosquito surveillance programs. We found that 0.9 cm2 cards impregnated with a 50% honey solution could replace the forced salivation technique as they offered a viral RNA detection until 7 days after oral infection of Aedes aegypti and Aedes albopictus mosquitoes with CHIKV.

Author(s):  
O. Diaz de Leon ◽  
M. Nassirian ◽  
C. Todd ◽  
R. Chowdhury

Abstract Integration of circuits on semiconductor devices with resulting increase in pin counts is driving the need for improvements in packaging for functionality and reliability. One solution to this demand is the Flip- Chip concept in Ultra Large Scale Integration (ULSI) applications [1]. The flip-chip technology is based on the direct attach principle of die to substrate interconnection.. The absence of bondwires clearly enables packages to become more slim and compact, and also provides higher pin counts and higher-speeds [2]. However, due to its construction, with inherent hidden structures the Flip-Chip technology presents a challenge for non-destructive Failure Analysis (F/A). The scanning acoustic microscope (SAM) has recently emerged as a valuable evaluation tool for this purpose [3]. C-mode scanning acoustic microscope (C-SAM), has the ability to demonstrate non-destructive package analysis while imaging the internal features of this package. Ultrasonic waves are very sensitive, particularly when they encounter density variations at surfaces, e.g. variations such as voids or delaminations similar to air gaps. These two anomalies are common to flip-chips. The primary issue with this package technology is the non-uniformity of the die attach through solder ball joints and epoxy underfill. The ball joints also present defects as open contacts, voids or cracks. In our acoustic microscopy study packages with known defects are considered. It includes C-SCAN analysis giving top views at a particular package interface and a B-SCAN analysis that provides cross-sectional views at a desired point of interest. The cross-section analysis capability gives confidence to the failure analyst in obtaining information from a failing area without physically sectioning the sample and destroying its electrical integrity. Our results presented here prove that appropriate selection of acoustic scanning modes and frequency parameters leads to good reliable correlation between the physical defects in the devices and the information given by the acoustic microscope.


Pathogens ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 947
Author(s):  
Rishi Kondapaneni ◽  
Ashley N. Malcolm ◽  
Brian M. Vazquez ◽  
Eric Zeng ◽  
Tse-Yu Chen ◽  
...  

Florida lies within a subtropical region where the climate allows diverse mosquito species including invasive species to thrive year-round. As of 2021, there are currently 66 state-approved Florida Mosquito Control Districts, which are major stakeholders for Florida public universities engaged in mosquito research. Florida is one of the few states with extensive organized mosquito control programs. The Florida State Government and Florida Mosquito Control Districts have long histories of collaboration with research institutions. During fall 2020, we carried out a survey to collect baseline data on the current control priorities from Florida Mosquito Control Districts relating to (1) priority control species, (2) common adult and larval control methods, and (3) major research questions to address that will improve their control and surveillance programs. The survey data showed that a total of 17 distinct mosquito species were considered to be priority control targets, with many of these species being understudied. The most common control approaches included truck-mounted ultra-low-volume adulticiding and biopesticide-based larviciding. The districts held interest in diverse research questions, with many prioritizing studies on basic science questions to help develop evidence-based control strategies. Our data highlight the fact that mosquito control approaches and priorities differ greatly between districts and provide an important point of comparison for other regions investing in mosquito control, particularly those with similar ecological settings, and great diversity of potential mosquito vectors, such as in Florida. Our findings highlight a need for greater alignment of research priorities between mosquito control and mosquito research. In particular, we note a need to prioritize filling knowledge gaps relating to understudied mosquito species that have been implicated in arbovirus transmission.


2021 ◽  
Vol 6 (1) ◽  
pp. 25
Author(s):  
Cameron E. Webb ◽  
Philippe G. Porigneaux ◽  
David N. Durrheim

Exotic mosquitoes, especially container-inhabiting species such as Aedes aegypti and Aedes albopictus, pose a risk to Australia as they bring with them potentially significant pest and public health concerns. Notwithstanding the threat to public health and wellbeing, significant economic costs associated with the burden of mosquito control would fall to local authorities. Detection of these mosquitoes at airports and seaports has highlighted pathways of introduction but surveillance programs outside these first ports of entry are not routinely conducted in the majority of Australian cities. To assist local authorities to better prepare response plans for exotic mosquito incursions, an investigation was undertaken to determine the extent of habitats suitable for container-inhabiting mosquitoes in over 300 residential properties adjacent to the Port of Newcastle, Newcastle, NSW. More than 1500 water-holding containers were recorded, most commonly pot plant saucers, roof gutters, and water-holding plants (e.g., bromeliads). There were significantly more containers identified for properties classified as untidy but there was no evidence visible that property characteristics could be used to prioritise property surveys in a strategic eradication response. The results demonstrate that there is potential for local establishment of exotic mosquitoes and that considerable effort would be required to adequately survey these environments for the purpose of surveillance and eradication programs.


Author(s):  
Mohammad Jahidur Rahman Khan ◽  
◽  
Selim Reza ◽  
Farzana Mim ◽  
Md Abdullah Rumman ◽  
...  

Rapid and accurate laboratory diagnosis of SARS-CoV-2 infection is crucial for the management of COVID-19 patients and control of the spread of the virus. At the start of the COVID-19 pandemic, Bangladesh had only one government molecular laboratory where real-time RT-PCR will be performed to diagnose SARS-CoV-2 infection. With the increasing number of suspected cases requiring confirmation diagnostic testing, there was a requirement to quickly expand capacity for large-scale testing. The government of Bangladesh established over 100 molecular laboratories within one year to test COVID-19. To fulfil the requirement for expanded testing, the government was compelled to recruit laboratory employees with inadequate experience, technical knowledge, and skills in molecular assays, particularly in processing specimens, interpreting results, recognizing errors, and troubleshooting. As a result, the risk of diagnostic errors, such as cross-contamination, is increased, as is that the risk of false-positive results, which might risk the patient’s health and undermine the efficacy of public health policies, public health response, surveillance programs, and restrictive measures aimed toward containing the outbreak. This review article aims to explain different sources of crosscontamination in the COVID-19 RT-PCR laboratories and the way to forestall them in efficient and practical ways.


Author(s):  
Andrew Celovsky ◽  
John Slade

CANDU reactors use Zr-2.5 Nb alloy pressure tubes, as the primary pressure boundary within the reactor core. These components are subject to periodic inspection and material surveillance programs. Occasionally, the inspection program uncovers a flaw, whereupon the flaw is assessed as to whether it compromises the integrity of the pressure-retaining component. In 1998, such a flaw was observed in one pressure tube of a reactor. Non-destructive techniques and analysis were used to form a basis to disposition the flaw, and the component was fit for a limited service life. This component was eventually removed from service, whereupon the destructive examinations were used to validate the disposition assumptions used. Such a process of validation provides credibility to the disposition process. This paper reviews the original flaw and its subsequent destructive evaluation.


2019 ◽  
Vol 72 ◽  
pp. 195-204
Author(s):  
Mana Kanjanamaneesathian ◽  
Wasunan Nimanong

The bacterium Bacillus megaterium can be used to biologically control sheath blight and grain discoloration in rice. Large-scale inoculations using liquid cultures are cumbersome so the efficacy of an alternative, paper-based system was examined. Bacterial endospores were embedded on filter papers and multiplied using a simple culture technique. The resulting suspension was used to pre-soak yardlong bean and cucumber seeds before sowing to assess its effect on seed germination and weight. The efficacy of the bacterium in protecting cucumber seeds from pre-emergent damping-off was also examined. The population of bacteria embedded in paper declined initially but remained stable for 150 days at room temperature. Bacterial culture reduced seed germination of cucumber and seedling weight of yardlong beans. Dilution with water either increased or reduced germination of cucumber seeds depending on concentration. A 1:10 v/v dilution increased cucumber-seed germination in a pre-emergent damping-off pot test but all seedlings later died, irrespective of treatment. Paper-based inoculum has the potential to replace liquid inoculum but further work is required to optimise the concentrations of the bacterial culture to achieve disease control without adversely affecting the host plant.


2018 ◽  
Vol 8 (2) ◽  
pp. 20170048 ◽  
Author(s):  
M. I. Disney ◽  
M. Boni Vicari ◽  
A. Burt ◽  
K. Calders ◽  
S. L. Lewis ◽  
...  

Terrestrial laser scanning (TLS) is providing exciting new ways to quantify tree and forest structure, particularly above-ground biomass (AGB). We show how TLS can address some of the key uncertainties and limitations of current approaches to estimating AGB based on empirical allometric scaling equations (ASEs) that underpin all large-scale estimates of AGB. TLS provides extremely detailed non-destructive measurements of tree form independent of tree size and shape. We show examples of three-dimensional (3D) TLS measurements from various tropical and temperate forests and describe how the resulting TLS point clouds can be used to produce quantitative 3D models of branch and trunk size, shape and distribution. These models can drastically improve estimates of AGB, provide new, improved large-scale ASEs, and deliver insights into a range of fundamental tree properties related to structure. Large quantities of detailed measurements of individual 3D tree structure also have the potential to open new and exciting avenues of research in areas where difficulties of measurement have until now prevented statistical approaches to detecting and understanding underlying patterns of scaling, form and function. We discuss these opportunities and some of the challenges that remain to be overcome to enable wider adoption of TLS methods.


Pathogens ◽  
2020 ◽  
Vol 9 (6) ◽  
pp. 442
Author(s):  
Nathamon Kosoltanapiwat ◽  
Jarinee Tongshoob ◽  
Preeraya Singkhaimuk ◽  
Chanyapat Nitatsukprasert ◽  
Silas A. Davidson ◽  
...  

Entomological surveillance for arthropod-borne viruses is vital for monitoring vector-borne diseases and informing vector control programs. In this study, we conducted entomological surveillance in Zika virus endemic areas. In Thailand, it is standard protocol to perform mosquito control within 24 h of a reported dengue case. Aedes females were collected within 72 h of case reports from villages with recent Zika–human cases in Kamphaeng Phet Province, Thailand in 2017 and 2018. Mosquitoes were bisected into head-thorax and abdomen and then screened for Zika (ZIKV) and dengue (DENV) viruses using real-time RT-PCR. ZIKV RNA was detected in three samples from two female Ae. aegypti (1.4%). A partial envelope sequence analysis revealed that the ZIKV sequences were the Asian lineage identical to sequences from ZIKV-infected cases reported in Thailand during 2016 and 2017. Dengue virus-1 (DENV-1) and dengue virus-4 (DENV-4) were found in four Ae. aegypti females (2.8%), and partial capsid sequences were nearly identical with DENV-1 and DENV-4 from Thai human cases reported in 2017. Findings in the current study demonstrate the importance of entomological surveillance programs to public health mosquito-borne disease prevention measures and control.


2012 ◽  
Vol 45 (4) ◽  
pp. 231-239 ◽  
Author(s):  
B. Borkenhagen ◽  
H. Doscher ◽  
T. Hannappel ◽  
G. Lilienkamp ◽  
W. Daum

2014 ◽  
Vol 22 (3) ◽  
pp. 291-297 ◽  
Author(s):  
Harry E. Prince ◽  
Brent L. Seaton ◽  
Jose L. Matud ◽  
Hollis J. Batterman

ABSTRACTSince first reported in the Americas in December 2013, chikungunya virus (CHIKV) infections have been documented in travelers returning from the Caribbean, with many cases identified by CHIKV antibody and/or RNA testing at our laboratory. We used our large data set to characterize the relationship between antibody titers and RNA detection and to estimate IgM persistence. CHIKV RNA was measured by nucleic acid amplification and CHIKV IgG/IgM by indirect immunofluorescence. Of the 1,306 samples submitted for RNA testing in January through September 2014, 393 (30%) were positive; for 166 RNA-positive samples, CHIKV antibody testing was also ordered, and 84% were antibody negative. Of the 6,971 sera submitted for antibody testing in January through September 2014, 1,811 (26%) were IgM positive; 1,461 IgM positives (81%) were also IgG positive. The relationship between the CHIKV antibody titers and RNA detection was evaluated using 376 IgM-positive samples (138 with RNA testing ordered and 238 deidentified and tested for RNA). RNA detection showed no significant association with the IgM titer but was inversely related to the IgG titer; 63% of the IgG negative sera were RNA positive, compared to 36% of sera with low IgG titers (1:10 to 1:80) and 16% with IgG titers of ≥1:160. Using second-sample results from 62 seroconverters, we estimated that CHIKV IgM persists for 110 days (95% confidence interval, 78 to 150 days) after the initial antibody-negative sample. These findings indicate that (i) RNA detection is more sensitive than antibody detection early in CHIKV infection, (ii) in the absence of RNA results, the IgG titer of the IgM-positive samples may be a useful surrogate for viremia, and (iii) CHIKV IgM persists for approximately 4 months after symptom onset.


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