scholarly journals Effectiveness of a Long-Lasting Insecticide Treatment Kit (ICON® Maxx) for Polyester Nets Over Three Years of Household use: A WHO Phase III Trial in Tanzania

2021 ◽  
Author(s):  
Patrick Tungu ◽  
Wema Sudi ◽  
William Kisinza ◽  
Mark Rowland
Keyword(s):  
Positive Control ◽  
Phase Iii ◽  
Cross Sectional Survey ◽  
Cross Sectional ◽  
Insecticide Treatment ◽  
Mosquito Nets ◽  
Lambda Cyhalothrin ◽  
Hole Index ◽  
Efficacy Criteria ◽  
Prospective Study Design

Abstract BackgroundICON® Maxx (Syngenta) is an insecticide treatment kit of pyrethroid and binding agent for long-lasting treatment of mosquito nets. Interim recommendation for use on nets was granted by WHO after successful evaluation in experimental huts following multiple washes. A full WHO recommendation is contingent upon demonstration of continued bio-efficacy after 3 years of use. MethodsA household-randomised prospective study design was used to assess ICON Maxx treated nets over 3 years in north-eastern Tanzania. Conventional treated nets (with lambda-cyhalothrin but without binder) served as a positive control. At 6-monthly intervals, cross-sectional household surveys monitored net use and physical integrity, while cone and tunnel tests assessed insecticidal efficacy. Pyrethroid content was determined after 12 and 36 months. A parallel cohort of nets was monitored annually for evidence of net deterioration and attrition. ResultsAfter 12 months’ use, 97% of ICON Maxx treated nets but only 67% of CTN passed the WHO efficacy threshold for insecticidal durability (>80% mortality in cone or tunnel or 90% feeding inhibition in tunnel). After 24- and 36-months use, 67% and 26% of ICON Maxx treated nets met the cone criteria respectively and over 90% met the combined cone and tunnel criteria. Lambda-cyhalothrin content after 36 months was 17% (15.8 ± 4.3 mg/m2) of initial content. ICON Maxx nets were used year-round and washed approximately 4 times per year. In cross-sectional survey after 36 months the average number of holes was 20 and hole index was 740 cm2 per net. Cohort nets had fewer holes and smaller hole index than cross-sectional nets. However, only 15% (40/264) of cohort nets were not lost to follow-up or not worn out after 36 months.ConclusionsBecause more than 80% of nets met the WHO efficacy criteria after 36 months use, ICON Maxx was granted WHO full recommendation. Cross-sectional and cohort surveys were complementary and gave a fuller understanding of net durability. To improve net usage and retention, stronger incentives and health messaging should be introduced in WHO LLIN longitudinal trials. Untreated polyester nets may be made long-lastingly insecticidal in Africa through simple household treatment using ICON Maxx pyrethroid-binder kits.

scholarly journals Effectiveness of a long-lasting insecticide treatment kit (ICON® Maxx) for polyester nets over three years of household use: a WHO phase III trial in Tanzania

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Patrick K. Tungu ◽  
Wema Sudi ◽  
William Kisinza ◽  
Mark Rowland
Keyword(s):  
Positive Control ◽  
Phase Iii ◽  
World Health ◽  
Cross Sectional Survey ◽  
Cross Sectional ◽  
Insecticide Treatment ◽  
Lambda Cyhalothrin ◽  
Hole Index ◽  
Health Organization ◽  
Prospective Study Design

Abstract Background ICON® Maxx (Syngenta) is an insecticide treatment kit of pyrethroid and binding agent for long-lasting treatment of mosquito nets. Interim recommendation for use on nets was granted by the World Health Organization (WHO) after successful evaluation in experimental huts following multiple washes. A full WHO recommendation is contingent upon demonstration of continued bio-efficacy after 3 years of use. Methods A household-randomized prospective study design was used to assess ICON Maxx-treated nets over 3 years in north-eastern Tanzania. Conventional treated nets (with lambda-cyhalothrin, but without binder) served as a positive control. At 6-monthly intervals, cross-sectional household surveys monitored net use and physical integrity, while cone and tunnel tests assessed insecticidal efficacy. Pyrethroid content was determined after 12 and 36 months. A parallel cohort of nets was monitored annually for evidence of net deterioration and attrition. Results After 12 months’ use, 97% of ICON Maxx-treated nets but only 67% of CTN passed the WHO efficacy threshold for insecticidal durability (> 80% mortality in cone or tunnel or 90% feeding inhibition in tunnel). After 24- and 36-months use, 67% and 26% of ICON Maxx treated nets met the cone criteria, respectively, and over 90% met the combined cone and tunnel criteria. Lambda-cyhalothrin content after 36 months was 17% (15.8 ± 4.3 mg/m2) of initial content. ICON Maxx nets were used year-round and washed approximately 4 times per year. In cross-sectional survey after 36 months the average number of holes was 20 and hole index was 740 cm2 per net. Cohort nets had fewer holes and smaller hole index than cross-sectional nets. However, only 15% (40/264) of cohort nets were not lost to follow-up or not worn out after 36 months. Conclusions Because more than 80% of nets met the WHO efficacy criteria after 36 months use, ICON Maxx was granted WHO full recommendation. Cross-sectional and cohort surveys were complementary and gave a fuller understanding of net durability. To improve net usage and retention, stronger incentives and health messaging should be introduced in WHO LLIN longitudinal trials. Untreated polyester nets may be made long-lastingly insecticidal in Africa through simple household treatment using ICON Maxx pyrethroid-binder kits.

scholarly journals Asthma in South African adolescents: a time trend and risk factor analysis over two decades

2020 ◽  
pp. 00576-2020
Author(s):  
C.B. Baard ◽  
Z. Franckling-Smith ◽  
J. Munro ◽  
L. Workman ◽  
H.J. Zar
Keyword(s):  
Risk Factors ◽  
South African ◽  
Severe Asthma ◽  
Time Trend ◽  
Self Report ◽  
Phase Iii ◽  
Social Risk ◽  
Cross Sectional Survey ◽  
Cross Sectional ◽  
Current Asthma

BackgroundSouth Africa has undergone major economic and health system changes impacting the epidemiology of childhood asthma. This study aimed to investigate prevalence time-trends of asthma in South African adolescents over 2 decades and to identify associated risk-factors.MethodsA cross-sectional survey was conducted in 2017, in a randomised sample of 13–14 year-old Cape Town adolescents, using the standardised Global Asthma Network written, video, and environmental questionnaires. Using time-trend analysis, the prevalence and severity of asthma were compared with data from the 2002 ISAAC phase III study. Environmental and social risk-factors were analysed.Results3979 adolescents were included. Prevalence of lifetime and current asthma were 34.5% and 21.3%, respectively, on the self-report written questionnaire, similar to 2002 results. The prevalence of severe asthma in the last 12 months increased, measured by wheeze limiting speech (7.8% to 11.8%), ≥4 attacks of wheezing (5.0% to 5.8%) or ≥1 night·week−1 waking from wheezing (5.0% to 6.9%). The video questionnaire revealed increases in lifetime (16.9% to 22.5%), current (11.2% to 18.7%), or severe asthma (12.1% to 14.8%). Multivariate analysis showed associations between current asthma and smoking, female sex, pet exposure or higher socioeconomic status. Severe asthma was associated with smoking, pet exposure, outdoor pollution exposure or informal housing. 33% of those with severe or current asthma had been diagnosed.ConclusionThe prevalence of asthma is high, with increasing rates of severe asthma in adolescents. Underdiagnosis is a major concern and reduction in exposure to environmental factors, particularly smoking, and improved socioeconomic development are needed.

Different Methods to Calculate Effect Estimates in Cross-sectional Studies

2004 ◽  
Vol 43 (05) ◽  
pp. 505-509 ◽  
Author(s):  
D. Taeger ◽  
J. Wellmann ◽  
U. Keil ◽  
T. Behrens
Keyword(s):  
Confidence Intervals ◽  
Poisson Regression ◽  
Phase Iii ◽  
Traffic Density ◽  
Binomial Model ◽  
Cross Sectional Survey ◽  
Prevalence Odds Ratio ◽  
Cross Sectional ◽  
Cross Sectional Studies ◽  
Log Linear

Summary Objectives: According to results from the epidemiological literature, it can be expected that the prevalence odds ratio (POR) and the prevalence ratio (PR) differ with increasing disease prevalence. We illustrate different concepts to calculate these effect measures in cross-sectional studies and discuss their advantages and weaknesses, using actual data from the ISAAC Phase III cross-sectional survey in Münster, Germany. Methods: We analyzed data on the association between self-reported traffic density and wheeze and asthma by means of the POR, obtained from a logistic regression, and the PR, which was estimated from a log-linear binomial model and from different variants of a Poisson regression. Results: The analysis based on the less frequent disease, i.e. asthma with an overall prevalence of 7.8%, yielded similar results for all estimates. When wheezing with a prevalence of 17.5% was analyzed, the POR produced the highest estimates with the widest confidence intervals. While the point estimates were similar in the log-binomial model and Poisson regression, the latter showed wider confidence intervals. When we calculated the Poisson regression with robust variances, confidence intervals narrowed. Conclusions: Since cross-sectional studies often deal with frequent diseases, we encourage analyzing cross-sectional data based on log-linear binomial models, which is the ‘natural method’ for estimating prevalence ratios. If algorithms fail to converge, a useful alternative is to define appropriate starting values or, if models still do not converge, to calculate a Poisson regression with robust estimates to control for overestimation of errors in the binomial data.

scholarly journals Perception to COVID-19 epidemic and acceptance of vaccination among healthcare workers in Beijing: a survey before the completion of COVID-19 vaccine phase III clinical trials

2020 ◽  
Author(s):  
Suo Luodan ◽  
Ma Rui ◽  
Wang Zhongzhan ◽  
Tang Tian ◽  
Wang Haihong ◽  
...  
Keyword(s):  
Clinical Trials ◽  
Healthcare Workers ◽  
Associated Factors ◽  
Vaccination Strategy ◽  
Phase Iii ◽  
Cross Sectional Survey ◽  
Cross Sectional ◽  
Academic Degree ◽  
Global Epidemic ◽  
Phase Iii Clinical Trials

Abstract Background: Covid-19 vaccine research and development is progressing and expected to be put into use in a predictable time, we aimed to learn the awareness and acceptance of the new vaccine by healthcare workers (HCWs) in Beijing, China. Methods: A cross-sectional survey was conducted to investigate HCWs including doctors, nurses and technicians from sixty hospitals in Beijing to obtain the perception of COVID-19 epidemic and the attitudes towards vaccination before before the completion of vaccine phase III clinical trials. Multivariate analysis was applied to evaluate the associated factors with intention to get vaccination.Results: A total of 8040 HCWs was recruited. 67.1% reported they would get vaccination, others said unsure or would not. Half of the HCWs were unsure whether the outbreak in China would come back and the global epidemic would last for a long time. 67.6% agreed the epidemic can be prevented by vaccination. Positive associated factors with willingness to get vaccination were mainly included epidemic situation prognosis, perception of disease severity, self infection risk and disease can be prevented by vaccine, etc. Two positive factors of “wanted the vaccine free of charge” (OR:5.807, 95%CI:5.083-6.635, P<0.001) and “believed vaccine approved for license have been fully evaluated in clinical trials” (OR:4.485, 95%CI:3.849-5.227, P<0.001) were strongly associated with willingness to get vaccination, while two factors of “highest academic degree” (OR:0.840, 95%CI:0.772-0.914, P<0.001) and “professional ranks and titles” (OR:0.930, 95%CI:0.865-1.000, P=0.049) were negative associated .Conclusions: A little above moderate willingness to get COVID-19 vaccination was found among HCWs in Beijing before the vaccine being licensed. Free vaccination strategy should be considered to implement, effective measures should be taken to remove barriers and convey correct information through appropriate ways to enhance the acceptance of COVID-19 vaccination among HCWs in China.

scholarly journals Community-based surveys for Plasmodium falciparum pfhrp2 and pfhrp3 gene deletions in selected regions of mainland Tanzania

2020 ◽  
Vol 19 (1) ◽  
Author(s):  
Catherine Bakari ◽  
Sophie Jones ◽  
Gireesh Subramaniam ◽  
Celine I. Mandara ◽  
Mercy G. Chiduo ◽  
...  
Keyword(s):  
Plasmodium Falciparum ◽  
Single Gene ◽  
False Negative ◽  
Malaria Diagnosis ◽  
Positive Control ◽  
Cross Sectional Survey ◽  
Community Based ◽  
Cross Sectional ◽  
Gene Deletions ◽  
Antigen Assay

Abstract Background Histidine-rich protein 2 (HRP2)-based malaria rapid diagnostic tests (RDTs) are effective and widely used for the detection of wild-type Plasmodium falciparum infections. Although recent studies have reported false negative HRP2 RDT results due to pfhrp2 and pfhrp3 gene deletions in different countries, there is a paucity of data on the deletions of these genes in Tanzania. Methods A community-based cross-sectional survey was conducted between July and November 2017 in four regions: Geita, Kigoma, Mtwara and Ruvuma. All participants had microscopy and RDT performed in the field and provided a blood sample for laboratory multiplex antigen detection (for Plasmodium lactate dehydrogenase, aldolase, and P. falciparum HRP2). Samples showing RDT false negativity or aberrant relationship of HRP2 to pan-Plasmodium antigens were genotyped to detect the presence/absence of pfhrp2/3 genes. Results Of all samples screened by the multiplex antigen assay (n = 7543), 2417 (32.0%) were positive for any Plasmodium antigens while 5126 (68.0%) were negative for all antigens. The vast majority of the antigen positive samples contained HRP2 (2411, 99.8%), but 6 (0.2%) had only pLDH and/or aldolase without HRP2. Overall, 13 samples had an atypical relationship between a pan-Plasmodium antigen and HRP2, but were positive by PCR. An additional 16 samples with negative HRP2 RDT results but P. falciparum positive by microscopy were also chosen for pfhrp2/3 genotyping. The summation of false negative RDT results and laboratory antigen results provided 35 total samples with confirmed P. falciparum DNA for pfhrp2/3 genotyping. Of the 35 samples, 4 (11.4%) failed to consistently amplify positive control genes; pfmsp1 and pfmsp2 and were excluded from the analysis. The pfhrp2 and pfhrp3 genes were successfully amplified in the remaining 31 (88.6%) samples, confirming an absence of deletions in these genes. Conclusions This study provides evidence that P. falciparum parasites in the study area have no deletions of both pfhrp2 and pfhrp3 genes. Although single gene deletions could have been missed by the multiplex antigen assay, the findings support the continued use of HRP2-based RDTs in Tanzania for routine malaria diagnosis. There is a need for the surveillance to monitor the status of pfhrp2 and/or pfhrp3 deletions in the future.

Sustainability of integrated anaemia prevention activities implemented through non-government organizations and schools, and its effect on haemoglobin status of adolescent girls in urban slums of Pune, in Maharashtra, India

2021 ◽  
pp. 026010602110096
Author(s):  
Angeline Jeyakumar ◽  
Shraddha Chalwadi ◽  
Pooja Madhu ◽  
Padmini Ghugre
Keyword(s):  
Phase I ◽  
Needs Assessment ◽  
Phase Ii ◽  
Adolescent Girls ◽  
Service Providers ◽  
Phase Iii ◽  
Cross Sectional Survey ◽  
Cross Sectional ◽  
Integrated Intervention ◽  
The Impact

Background: Programmes for the prevention of iron deficiency anaemia among adolescent girls need sustainable inputs for maximum benefits. Aim: To assess the interventions sustained for anaemia prevention implemented through NGOs and schools. Methods: An intervention study followed longitudinally in three phases. Phase I comprised (a) needs assessment of the community and (b) capacity assessment of service providers through a cross-sectional survey in nine slums, through six NGOs and three schools. Based on needs assessment, an integrated intervention for anaemia prevention was provided for adolescent girls ( n = 384) in the community. To ensure sustainability the capacity of stakeholders ( n = 67) was built by providing training in the components of the integrated intervention and establishing linkages with the public health system. Refresher training was conducted during phase II ( n = 69) for reinforcing and strengthening of activities introduced in phase I. In phase II and III continuations of activities by the NGOs and schools that were initiated in phase I were monitored. Sustainability of activities was measured using an index that comprised technical, programmatic, social, and financial indicators. The impact of sustained interventions was assessed by comparing the mean rank haemoglobin concentrations of centres with varying levels of coverage. Results: Scores of sustainability indicators decreased from phase II to phase III. Organizations that showed > 50% coverage showed significantly higher mean rank haemoglobin ( p = < 0.05) during phases II and III. Conclusion: There is a need to identify and address barriers that prevent sustainable interventions for anaemia control.

Testing the Strain Theory of Suicide – The Moderating Role of Social Support

Crisis ◽  
2020 ◽  
Vol 41 (2) ◽  
pp. 82-88 ◽  
Author(s):  
Bob Lew ◽  
Ksenia Chistopolskaya ◽  
Yanzheng Liu ◽  
Mansor Abu Talib ◽  
Olga Mitina ◽  
...  
Keyword(s):  
Social Support ◽  
Suicidal Behavior ◽  
Online Survey ◽  
Perceived Social Support ◽  
Strain Theory ◽  
Cross Sectional Survey ◽  
Cross Sectional ◽  
Psychological Strains ◽  
Moderating Role

Abstract. Background: According to the strain theory of suicide, strains, resulting from conflicting and competing pressures in an individual's life, are hypothesized to precede suicide. But social support is an important factor that can mitigate strains and lessen their input in suicidal behavior. Aims: This study was designed to assess the moderating role of social support in the relation between strain and suicidality. Methods: A sample of 1,051 employees were recruited in Beijing, the capital of China, through an online survey. Moderation analysis was performed using SPSS PROCESS Macro. Social support was measured with the Multidimensional Scale of Perceived Social Support, and strains were assessed with the Psychological Strains Scale. Results: Psychological strains are a good predictor of suicidality, and social support, a basic need for each human being, moderates and decreases the effects of psychological strains on suicidality. Limitations: The cross-sectional survey limited the extent to which conclusions about causal relationships can be drawn. Furthermore, the results may not be generalized to the whole of China because of its diversity. Conclusion: Social support has a tendency to mitigate the effects of psychological strains on suicidality.

Fit and Congruency

2019 ◽  
Vol 18 (3) ◽  
pp. 148-156
Author(s):  
Mary Hogue ◽  
Lee Fox-Cardamone ◽  
Deborah Erdos Knapp
Keyword(s):  
Role Theory ◽  
Social Role ◽  
Gender Diversity ◽  
Job Fit ◽  
Cross Sectional Survey ◽  
Cross Sectional ◽  
Working Adults ◽  
Role Congruity ◽  
Self Selection ◽  
Selection Of

Abstract. Applicant job pursuit intentions impact the composition of an organization’s applicant pool, thereby influencing selection outcomes. An example is the self-selection of women and men into gender-congruent jobs. Such self-selection contributes to a lack of gender diversity across a variety of occupations. We use person-job fit and the role congruity perspective of social role theory to explore job pursuit intentions. We present research from two cross-sectional survey studies (520 students, 174 working adults) indicating that at different points in their careers women and men choose to pursue gender-congruent jobs. For students, the choice was mediated by value placed on the job’s associated gender-congruent outcomes, but for working adults it was not. We offer suggestions for practitioners and researchers.

Oscillation between identities and Subjective psychological health objectives among an informed audience in therapeutic patient education

2018 ◽  
Vol 10 (1) ◽  
pp. 10202
Author(s):  
Sandrine Roussel ◽  
Alain Deccache ◽  
Mariane Frenay
Keyword(s):  
Patient Education ◽  
Psychological Health ◽  
Healthcare Professionals ◽  
Cross Sectional Survey ◽  
Chi Square ◽  
Cross Sectional ◽  
Therapeutic Patient Education ◽  
French Speaking ◽  
Health Objectives ◽  
Self Administered Questionnaire

Introduction: The implementation of Therapeutic Patient Education (TPE) remains a challenge. An exploratory study highlighted two tendencies among practitioners of TPE, which could hamper this implementation: an oscillation between identities (as caregivers versus as educators) and an inclination towards subjective psychological health objectives. Objectives: To verify whether these tendencies can be observed among an informed audience in TPE. Next, to explore the variables associated with one or other of these tendencies. Method: A quantitative cross-sectional survey by a self-administered questionnaire was carried out among 90 French-speaking healthcare professionals. Statistical analyses (chi-square, logistic regression) were then conducted. Results: Sixty percent of respondents displayed identity oscillation, which was found to be linked to task oscillation, patient curability, scepticism towards medicine and practising in France. Fifty-six percent pursued subjective psychological health objectives, which was found to be associated with health behaviour objectives and a locus of power in the healthcare relationship distinct from those seen in the pre-existing health models (biomedical, global). This tendency seems to constitute an alternative model of TPE. Discussion & conclusion: Identity oscillation and subjective psychological health objectives can be both observed. This study stresses the need to deliberate on the form(s) of TPE that is/are desired.

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