Psychometric Properties of a Safety Culture Index among Mental Health Workers in Ghana

Safety culture among mental health workers is essential, especially in developing countries where workplace safety seems neglected. However, few studies have provided detailed psychometric analyses of convenient safety instruments with practical relevance for the healthcare industry in the Sub-Saharan African context. We sampled 574 (54.4 % females, 45.6 % males) mental health workers from three Specialist Psychiatric Teaching Hospitals in Ghana. Initially, we collected data using adapted items from Edkins and Coakes’ 25-item Airline Safety Culture Index (ASCI). Consequently, we conducted a Confirmatory Factor Analysis (CFA) using the Diagonally Weighted Least Squares estimator. We also used the item reduction analysis (Gradual Response Model) to reduce the adapted 25-item scale to 11 items (Modified Safety Culture Index, MSCI- 11). Finally, we conducted reliability analyses (alpha and omega) for the MSCI-11. We observed that the data in the CFA showed adequate fit indices [χ2 (df = 44, N = 574) = 223.752, p < 0.001; CFI = 0.975; TLI = 0.968; RM- SEA = 0.084 (CI 90 % 0.074- 0.096); SRMR = 0.063]. The MSCI- 11 is parsimonious and has good reliability estimates [α = 0.853 (95 % CI 0.835 – 0.870) and ω = 0.853 (95 % CI 0.837- 0.087)]. Future studies should use additional cross-validation in other high-risk jobs to generalise the new scale

Detection of Mycolactone A/B in Mycobacterium ulcerans–Infected Human Tissue

Skin infection with bacteria called Mycobacterium ulcerans causes Buruli ulcer, a disease common in West Africa and mainly affecting children. M. ulcerans is the only mycobacterium to cause disease by production of a toxin. This lipid molecule called mycolactone diffuses from the site of infection, killing surrounding cells and, at low concentration, suppressing the immune response. The aim of this study was to show that mycolactone can be detected among lipids extracted from human M. ulcerans lesions in order to study its role in the pathogenesis of M. ulcerans disease. Lipids were extracted from skin biopsies and tested for the presence of mycolactone using thin layer chromatography and mass spectrometry. The extracts were shown to kill cultured cells in a cytotoxicity assay. Mycolactone was detected in both pre-ulcerative and ulcerative forms of the disease and also in lesions during antibiotic treatment but with reduced bioactivity, suggesting a lower concentration compared to untreated lesions. These findings indicate that there is mycolactone in affected skin at all stages of M. ulcerans disease and it could be used as a biomarker for monitoring the clinical response to antibiotic treatment

Association between functional antibody against Group B Streptococcus and maternal and infant colonization in a Gambian cohort.

BACKGROUND: Vertical transmission of Group B Streptococcus (GBS) is a prerequisite for early-onset disease and a consequence of maternal GBS colonization. Disease protection is associated with maternally-derived anti-GBS antibody. Using a novel antibody-mediated C3b/iC3b deposition flow cytometry assay which correlates with opsonic killing we developed a model to assess the impact of maternally-derived functional anti-GBS antibody on infant GBS colonization from birth to day 60-89 of life. METHODS: Rectovaginal swabs and cord blood (birth) and infant nasopharyngeal/rectal swabs (birth, day 6 and day 60-89) were obtained from 750 mother/infant pairs. Antibody-mediated C3b/iC3b deposition with cord and infant sera was measured by flow cytometry. RESULTS: We established that as maternally-derived anti-GBS functional antibody increases, infant colonization decreases at birth and up to three months of life, the critical time window for the development of GBS disease. Further, we observed a serotype (ST)-dependent threshold above which no infant was colonized at birth. Functional antibody above the upper 95th confidence interval for the geometric mean concentration was associated with absence of infant GBS colonization at birth for STII (p<0.001), STIII (p=0.01) and STV (p<0.001). Increased functional antibody was also associated with clearance of GBS between birth and day 60-89. CONCLUSIONS: Higher concentrations of maternally-derived antibody-mediated complement deposition are associated with a decreased risk of GBS colonization in infants up to day 60-89 of life. Our findings are of relevance to establish thresholds for protection following vaccination of pregnant women with future GBS vaccines

Impure Public Goods and Technological Interdependencies

Impure public goods represent an important group of goods. Almost every public good exerts not only effects which are public to all but also effects which are private to the producer of this good. What is often omitted in the analysis of impure public goods is the fact that – regularly – these private effects can also be generated independently of the public good. In our analysis we focus on the effects alternative technologies – independently generating the private effects of the public good – may have on the provision of impure public goods. After the investigation in an analytical impure public good model, we numerically simulate the effects of alternative technologies in a parameterized model for climate policy in Germany