Evaluation of the bag-mediated filtration system as a novel tool for poliovirus environmental surveillance: Results from a comparative field study in Pakistan

Abstract The bag-mediated filtration system (BMFS) was developed to facilitate poliovirus (PV) environmental surveillance, a supplement to acute flaccid paralysis surveillance in PV eradication efforts. From April to September 2015, environmental samples were collected from four sites in Nairobi, Kenya, and processed using two collection/concentration methodologies: BMFS (> 3 L filtered) and grab sample (1 L collected; 0.5 L concentrated) with two-phase separation. BMFS and two-phase samples were analyzed for PV by the standard World Health Organization poliovirus isolation algorithm followed by intratypic differentiation. BMFS samples were also analyzed by a cell culture independent real-time reverse transcription polymerase chain reaction (rRT-PCR) and an alternative cell culture method (integrated cell culture-rRT-PCR with PLC/PRF/5, L20B, and BGM cell lines). Sabin polioviruses were detected in a majority of samples using BMFS (37/42) and two-phase separation (32/42). There was statistically more frequent detection of Sabin-like PV type 3 in samples concentrated with BMFS (22/42) than by two-phase separation (14/42, p = 0.035), possibly due to greater effective volume assayed (870 mL vs. 150 mL). Despite this effective volume assayed, there was no statistical difference in Sabin-like PV type 1 and Sabin-like PV type 2 detection between these methods (9/42 vs. 8/42, p = 0.80 and 27/42 vs. 32/42, p = 0.18, respectively). This study demonstrated that BMFS can be used for PV environmental surveillance and established a feasible study design for future research.

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Wastewater based environmental surveillance of toxigenic Vibrio cholerae in Pakistan

PLoS ONE ◽

10.1371/journal.pone.0257414 ◽

2021 ◽

Vol 16 (9) ◽

pp. e0257414

Author(s):

Tanzeel Zohra ◽

Aamer Ikram ◽

Muhammad Salman ◽

Afreenish Amir ◽

Asim Saeed ◽

...

Keyword(s):

Seasonal Pattern ◽

Sampling Technique ◽

Environmental Surveillance ◽

Filtration System ◽

Significant Difference ◽

National Environment ◽

Clear Seasonal Pattern ◽

Sporadic Cases ◽

Multistage Sampling ◽

Positive Results

Background Pakistan has been experiencing intervals of sporadic cases and localized outbreaks in the last two decades. No proper study has been carried out in order to find out the environmental burden of toxigenic V. cholerae as well as how temporal and environmental factors associated in driving cholera across the country. Methods We tested waste water samples from designated national environment surveillance sites in Pakistan with RT-PCR assay. Multistage sampling technique were utilized for samples collection and for effective sample processing Bag-Mediated Filtration system, were employed. Results were analysed by district and month wise to understand the geographic distribution and identify the seasonal pattern of V. cholera detection in Pakistan. Results Between May 2019, and February 2020, we obtained and screened 160 samples in 12 districts across Pakistan. Out of 16 sentinel environmental surveillance sites, 15 sites showed positive results against cholera toxigenic gene with mostly lower CT value (mean, 34±2) and have significant difference (p < 0.05). The highest number of positive samples were collected from Sindh in month of November, then in June it is circulating in different districts of Pakistan including four Provinces respectively. Conclusion V. cholera detection do not follow a clear seasonal pattern. However, the poor sanitation problems or temperature and rainfall may potentially influence the frequency and duration of cholera across the country. Occurrence of toxigenic V. cholerae in the environment samples showed that cholera is endemic, which is an alarming for a potential future cholera outbreaks in the country.

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Field Evaluation of an Electrostatic Air Filtration System for Reducing Incoming Particulate Matter of a Hen House

Transactions of the ASABE ◽

10.13031/trans.12533 ◽

2018 ◽

Vol 61 (1) ◽

pp. 295-304 ◽

Cited By ~ 2

Author(s):

Yang Zhao ◽

Lilong Chai ◽

Brad Richardson ◽

Hongwei Xin

Keyword(s):

Particulate Matter ◽

Field Study ◽

Removal Efficiency ◽

Sampling Period ◽

Low Grade ◽

Air Filtration ◽

Late Fall ◽

Filtration System ◽

Pm Removal ◽

The U.S

Abstract. As a result of the unprecedented highly pathogenic avian influenza (HPAI) outbreak in the U.S. in 2014-2015, some egg producers in the U.S. started using inlet air filtration to reduce the risk of disease transmission by air into hen houses. The removal efficiency of particulate matter (PM), the carrier of airborne pathogens, by such filtration systems has not been investigated. Therefore, this field study was conducted to evaluate the PM removal efficacy of an electrostatic air filtration system (consisting of a low-grade air filter and an electrostatic particle ionization, or EPI, system) installed at the inlet of a commercial high-rise hen house. The evaluation was performed in two test rounds over a one-year period. Results showed that average PM removal efficiencies in round 1 (spring to summer) and round 2 (late fall to spring) were respectively 66% and 29% for PM1, 66% and 30% for PM2.5, 66% and 31% for PM4, 68% and 36% for PM10, and 68% and 45% for total PM. Removal efficiency became unstable when the EPI system was inactive (i.e., when solely relying on the filter for PM removal). House static pressure and ventilation rate indicated considerable clogging of the filter media by dust accumulation and the need for replacement after ~16 weeks of use in the spring-to-summer sampling period (round 1); however, clogging was not an issue during the entire late fall-to-spring sampling period (24 weeks, round 2). The appearance of the filter changed gradually as dust accumulated with time, which can be captured by image analysis and used to judge filter dirtiness and lifespan. The findings of this field study provide insight into the efficacy of PM removal by such a low-cost air filtration system, which will help egg producers in their decision-making for disease prevention strategies. Keywords: Electrostatic particle ionization, Filtration, Hen house, Particulate matter, Reduction.

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Validation of the bag‐mediated filtration system for environmental surveillance of poliovirus in Nairobi, Kenya

Journal of Applied Microbiology ◽

10.1111/jam.14807 ◽

2020 ◽

Author(s):

C.S. Fagnant‐Sperati ◽

Y. Ren ◽

N.A. Zhou ◽

E. Komen ◽

B. Mwangi ◽

...

Keyword(s):

Environmental Surveillance ◽

Filtration System

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Detection of potentially pathogenic enteric viruses in environmental samples from Kenya using the bag-mediated filtration system

Water Science & Technology Water Supply ◽

10.2166/ws.2019.046 ◽

2019 ◽

Vol 19 (6) ◽

pp. 1668-1676 ◽

Cited By ~ 2

Author(s):

Walda B. van Zyl ◽

Nicolette A. Zhou ◽

Marianne Wolfaardt ◽

Peter N. Matsapola ◽

Fhatuwani B. Ngwana ◽

...

Keyword(s):

Surface Waters ◽

Hepatitis A Virus ◽

Enteric Viruses ◽

Human Adenovirus ◽

Enteric Virus ◽

Environmental Surveillance ◽

Filtration System ◽

Global Issue ◽

Norovirus Gii ◽

Process Controls

Abstract Enteric virus environmental surveillance via a highly sensitive method is critical, as many enteric viruses have low infectious doses and can persist in the environment for extended periods. This study determined the potential of the novel bag-mediated filtration system (BMFS) to recover human enteric viruses and pepper mild mottle virus (PMMoV) from wastewater and wastewater-impacted surface waters, examined PMMoV use as a fecal contamination indicator in Kenya, and identified potential BMFS process controls. From April 2015 to April 2016, BMFS samples were collected from seven sites in Kenya (n = 59). Enteroviruses and PMMoV were detected in 100% of samples, and human adenovirus, human astrovirus, hepatitis A virus, norovirus GI, norovirus GII, sapovirus, and human rotavirus were detected in the majority of samples. The consistent detection of enteroviruses and PMMoV suggests that these viruses could be used as indicators in similarly fecally contaminated sites and BMFS process controls. As contamination of surface water sources remains a global issue, enteric virus environmental surveillance is necessary. This study demonstrates an effective way to sample large volumes of wastewater and wastewater-impacted surface waters for the detection of multiple enteric viruses simultaneously.

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Seminar and Field Study

Kappa Delta Pi Record ◽

10.1080/00228958.1966.10516624 ◽

1966 ◽

Vol 2 (4) ◽

pp. 146-146

Keyword(s):

Field Study

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Investigating the Unified Motive Scales

European Journal of Psychological Assessment ◽

10.1027/1015-5759/a000571 ◽

2020 ◽

pp. 1-5

Author(s):

Martin Bettschart ◽

Marcel Herrmann ◽

Benjamin M. Wolf ◽

Veronika Brandstätter

Keyword(s):

Field Study ◽

Predictive Validity ◽

Selection Process ◽

Police Department ◽

Longitudinal Field ◽

Explicit Motives ◽

Achievement Motive

Abstract. Explicit motives are well-studied in the field of personality and motivation psychology. However, the statistical overlap of different explicit motive measures is only moderate. As a consequence, the Unified Motive Scales (UMS; Schönbrodt & Gerstenberg, 2012 ) were developed to improve the measurement of explicit motives. The present longitudinal field study examined the predictive validity of the UMS achievement motive subscale. Applicants of a police department ( n = 168, Mage = 25.11, 53 females and 115 males) completed the UMS and their performance in the selection process was assessed. As expected, UMS achievement predicted success in the selection process. The findings provide first evidence for the predictive validity of UMS achievement in an applied setting.

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Employees’ Critical Thinking, Leaders’ Inspirational Motivation, and Voice Behavior

Journal of Personnel Psychology ◽

10.1027/1866-5888/a000193 ◽

2018 ◽

Vol 17 (1) ◽

pp. 33-41 ◽

Cited By ~ 4

Author(s):

Jing Jiang ◽

Ang Gao ◽

Baiyin Yang

Keyword(s):

Critical Thinking ◽

Field Study ◽

Voice Behavior ◽

Research And Practice ◽

Inspirational Motivation ◽

Positive Effect

Abstract. This study uses implicit voice theory to examine the influence of employees’ critical thinking and leaders’ inspirational motivation on employees’ voice behavior via voice efficacy. The results of a pretest of 302 employees using critical thinking questionnaires and a field study of 273 dyads of supervisors and their subordinates revealed that both employees’ critical thinking and leaders’ inspirational motivation had a positive effect on employees’ voice and that voice efficacy mediates the relationships among employees’ critical thinking, leaders’ inspirational motivation, and employees’ voice. Implications for research and practice are discussed.

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