Development and evaluation of a free-field voice test for potential use as a community screening tool for hearing impairment in children

Early identification of hearing impairment in children is essential to avoid potentially disabling effects of hearing loss or deafness. This necessitates effective screening measures appropriate to the community in question. Current methods used in South Africa, especially for pre-school and school going children have resulted in poor coverage as they are designed for the more developed countries. There is thus a need to devise a screening method that is appropriate to our local conditions. In this study, a free-field live voice test was developed based on three levels: whisper, conversational and loud. This was evaluated against pure tone audiometry for sensitivity, specificity, cost and ease of application in two studies: hospital and school- based. A total of 394 children were tested; 189 in hospital-based study and 205 in school based study. 378 of the total were eligible for analysis. In the hospital-based study, the results of 177 children were analysed. The age range was 3 - 12 years with a mean of 5.8 years. The sensitivity (ability of the test to detect hearing impairment) was 80.0%; and the specificity (ability to identify children with normal hearing) was 95.0%. In the school-based study, done after modification and standardisation of the test set, the sensitivity and specificity were 83.3% and 97.8% respectively. Age range was 3 - 8 years with 79% being 4- 6 years. In both studies, the voice test was simpler to perform, easily understood and acceptable to the children and the testers; and considerably cheaper as the only equipment required was picture/toy set. The main limitation was non-standardisation of the test set. This was rectified in the school-based study. The drawbacks noted were the inability of the voice test to detect unilateral hearing loss/deafness and high frequency hearing loss. The voice test generally correlated well with pure tone audiometry and could be used as alternative for screening for hearing impairment in the community especially for pre-school and school going children. However, it is recommended to repeat the study in actual community settings using Community Health Care Workers as the testers. This would also determine the reliability of the voice test, as this cannot be reliably established at this stage

Influence of basalt micro-fibres on the abrasion resistance of concrete in hydraulic structures

AbstractIn hydraulic structures, abrasion resistance can be a significant driver in concrete specification. Basalt micro-fibres represent a potentially sustainable construction product and have been shown to provide various benefits in concrete, however the implications for hydrodynamic abrasion resistance are to date unclear. This paper is the first investigation of its kind to examine the abrasion resistance of basalt fibre-reinforced (BFR) concretes using the ASTM C1138 underwater test method. Towards this, concretes incorporating fibre dosages of 0.5, 1, 1.5 and 3 kg/m3 were tested. The relationships between concrete abrasion and its fundamental mechanical properties are evaluated. For the particular concretes examined, it is found that based on the Shapiro-Wilks tests at 95% confidence, abrasion loss in BFR concretes followed a normal distribution; the use of basalt fibre in contents of up to 3 kg/m3 did not have a significant effect on abrasion resistance, compressive and tensile splitting strengths, as well as modulus of elasticity. It can be concluded that basalt micro-fibre can be used for their other attributes such as controlling bleeding, shrinkage and plastic cracking in concrete hydraulic structures without deleterious effects on abrasion resistance. The regression models proposed to predict concrete abrasion loss from its mechanical properties were found to be only significant at 48 h for compressive strength and 24 h for both tensile splitting strength and modulus of elasticity.</jats:p

Field Investigation into Abrasion of Concrete at a Coastal Stepped Revetment: A U.K. Case Study

Although concrete abrasion damage is a major maintenance challenge for coastal structures fronted by beaches with hard coarse sediments, there are no readily available field studies that have measured abrasion damage of known concrete mixtures under defined exposure conditions. The objective of this investigation is to evaluate the abrasive exposure conditions of the concrete revetment armour units at Cleveleys on the Fylde coast of the U.K. and examine the feasibility of using terrestrial laser scanning (TLS) to measure concrete abrasion damage in field conditions. It was found that the concrete elements at Cleveleys are exposed to a macro-tidal environment, which experiences significant wave heights that vary from 0.42 to 1.92 m, whilst the peak wave periods range from 3.7 to 6.5 s. The beach sediments have a mean size of 26 mm and are moderately sorted. TLS provides a dense point cloud of abraded surfaces suitable for quantitative assessment of concrete abrasion in the field. Based on the measured abrasion depths and exposure durations, the peak concrete abrasion rates at the site varied from 3.5 to 4.5 mm/year, and severe abrasion was concentrated in the region between mean high-water springs and mean high-water neaps, wherein the highest beach levels were also found during the survey. Finally, the abraded surfaces exhibited a polished texture with no visible craters; thus, the mechanism of concrete material loss was by grinding/polishing due to rolling/sliding sediments

Effect of HIV-1 and increasing immunosuppression on malaria parasitaemia and clinical episodes in adults in rural Uganda: a cohort study.

BACKGROUND: An association between HIV-1 and malaria is expected in theory, but has not been convincingly shown in practice. We studied the effects of HIV-1 infection and advancing immunosuppression on falciparum parasitaemia and clinical malaria. METHODS: HIV-1-positive and HIV-1-negative adults selected from a population-based cohort in rural Uganda were invited to attend a clinic every 3 months (routine visits) and whenever they were sick (interim visits). At each visit, information was collected on recent fever, body temperature, and malaria parasites. Participants were assigned a clinical stage at each routine visit and had regular CD4-cell measurements. FINDINGS: 484 participants made 7220 routine clinic visits between 1990 and 1998. Parasitaemia was more common at visits by HIV-1-positive individuals (328 of 2788 [11.8%] vs 231 of 3688 [6.3%], p<0.0001). At HIV-1-positive visits, lower CD4-cell counts were associated with higher parasite densities, compared with HIV-1-negative visits (p=0.0076). Clinical malaria was significantly more common at HIV-1-positive visits (55 of 2788 [2.0%] vs 26 of 3688 [0.7%], p=0.0003) and the odds of having clinical malaria increased with falling CD4-cell count (p=0.0002) and advancing clinical stage (p=0.0024). Participants made 3377 interim visits. The risk of clinical malaria was significantly higher at visits by HIV-1-positive individuals than HIV-1-negative individuals (4.0% vs 1.9%, p=0.009). The risk of clinical malaria tended to increase with falling CD4-cell counts (p=0.052). INTERPRETATION: HIV-1 infection is associated with an increased frequency of clinical malaria and parasitaemia. This association tends to become more pronounced with advancing immunosuppression, and could have important public-health implications for sub-Saharan Africa

Effect of HIV-1 and increasing immunosuppression on malaria parasitaemia and clinical episodes in adults in rural Uganda: a cohort study.

BACKGROUND: An association between HIV-1 and malaria is expected in theory, but has not been convincingly shown in practice. We studied the effects of HIV-1 infection and advancing immunosuppression on falciparum parasitaemia and clinical malaria. METHODS: HIV-1-positive and HIV-1-negative adults selected from a population-based cohort in rural Uganda were invited to attend a clinic every 3 months (routine visits) and whenever they were sick (interim visits). At each visit, information was collected on recent fever, body temperature, and malaria parasites. Participants were assigned a clinical stage at each routine visit and had regular CD4-cell measurements. FINDINGS: 484 participants made 7220 routine clinic visits between 1990 and 1998. Parasitaemia was more common at visits by HIV-1-positive individuals (328 of 2788 [11.8%] vs 231 of 3688 [6.3%], p<0.0001). At HIV-1-positive visits, lower CD4-cell counts were associated with higher parasite densities, compared with HIV-1-negative visits (p=0.0076). Clinical malaria was significantly more common at HIV-1-positive visits (55 of 2788 [2.0%] vs 26 of 3688 [0.7%], p=0.0003) and the odds of having clinical malaria increased with falling CD4-cell count (p=0.0002) and advancing clinical stage (p=0.0024). Participants made 3377 interim visits. The risk of clinical malaria was significantly higher at visits by HIV-1-positive individuals than HIV-1-negative individuals (4.0% vs 1.9%, p=0.009). The risk of clinical malaria tended to increase with falling CD4-cell counts (p=0.052). INTERPRETATION: HIV-1 infection is associated with an increased frequency of clinical malaria and parasitaemia. This association tends to become more pronounced with advancing immunosuppression, and could have important public-health implications for sub-Saharan Africa

Subtypes A1 and D, and recombinant HIV-1 natural polymorphisms associated with lenacapavir drug resistance in Uganda.

BACKGROUND: Lenacapavir, a novel HIV-1 capsid inhibitor, shows promise for treating MDR HIV-1, as well as for pre-exposure prophylaxis (PrEP) in prevention of HIV infection. Its unique mechanism and lack of cross-resistance with other antiretroviral classes make lenacapavir a significant addition to HIV therapy. The clinical trials CALIBRATE and CAPELLA have demonstrated high viral suppression rates in both ART-naive individuals and individuals with MDR HIV-1. Lenacapavir-associated resistance mutations, such as M66I and Q67H, rarely seen as natural polymorphisms in lenacapavir-naive populations, are predominantly studied in subtype B HIV-1. OBJECTIVES: Our study aimed to investigate the prevalence of lenacapavir resistance-associated mutations in HIV-1 subtypes A1 and D in a cohort of individuals living with HIV-1 from southwestern Uganda. METHODS: Utilizing plasma samples from ART-naive adults living in Uganda, HIV-1 Gag p24 (capsid) sequences were analysed for lenacapavir resistance mutations. RESULTS: Among 546 lenacapavir-naive participants, no major lenacapavir resistance-associated mutations were found. Minor mutations were present in 1.6% of participants, with T107A being the most common. Longitudinal data indicated the persistence of T107A for at least 3 years post-ART initiation in one participant. Phylogenetic analysis indicated individuals carrying T107A were found independently in distinct locations within the tree, suggesting that T107A might have arisen from multiple distinct base substitution events. Shannon entropy analysis showed high variability in certain capsid sites, but none overlapped with known lenacapavir resistance sites. CONCLUSIONS: These findings suggest a low prevalence of naturally occurring lenacapavir resistance mutations in Uganda, supporting lenacapavir's potential efficacy in this region.2026-01-3

Correlates of knowledge of family planning among people living in fishing communities of Lake Victoria, Uganda

Abstract Background: Knowledge of family planning (FP) is a key determinant of contraceptive use which ultimately plays a role in attainment of good health and in conduct of clinical research. People living in fishing communities (FCs) have limited access to health services including FP and are targeted for future clinical research but their knowledge of FP and its correlates are scantily known. We determined correlates of knowledge of FP among people living in FCs of L. Victoria in Uganda to inform future FP education programs in FCs. Methods: We conducted a comparative cross-sectional survey among participants aged 15-49 years from Kigungu and Nsazi. Participants were asked if they were aware of any FP method. All those who responded in the affirmative were further asked to mention what FP methods they had heard of or knew. Those who reported knowledge of at least one FP method were asked a series of questions about FP methods and their side effects. Knowledge was categorized into good or poor knowledge based on their mean total score. Poor knowledge constituted a score below the mean while good knowledge constituted a score of more than or equal to the mean total score. To further explore attitudes and perceptions of FP, ten in-depth interviews and four focus group discussions were conducted. Results: Of the 1,410 screened participants, 94.5% were aware of at least one FP method. Pills and injectable hormonal methods were the most commonly known methods. Slightly over a third (38%) had good knowledge of FP. Correlates of knowledge of FP were; being female (aOR: 1.92 95% CI: 1.39-2.67), residing in Kigungu (aOR: 4.01 95% CI: 2.77-5.81), being married (aOR: 1.59 95% CI: 1.11-2.28) and currently being in a sexual relationship (aOR: 1.75 95% CI: 1.18-2.60). Concerns about safety and effectiveness of some modern FP methods exist. Misconceptions on effects of FP like sterility, cancers and foetal abnormalities were common. Conclusion: FP awareness among people living in FCs of L. Victoria in Uganda is high. However, good knowledge about specific methods tends to be low. Correlates of knowledge of FP include gender, residence, marital status and sexual engagement.</jats:p