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Background: Variations in vaccine responses have been observed between populations. A role for helminth infections has been proposed due to their immunomodulatory properties. In a secondary analysis of data from a randomised trial assessing effects of anthelminthic treatment on vaccine responses, we examined associations between helminth infections at baseline prior to vaccine administration, and vaccine responses among adolescents (9-17 years) in Koome Islands, Lake Victoria, Uganda. Methods: Participants received BCG [week 0], yellow fever (YF-17D), oral typhoid (Ty21a), HPV-prime [week 4], and HPV-boost, tetanus/diphtheria [week 28]. Outcomes were BCG-specific interferon-g ELISpot responses and antibody responses to yellow-fever-, typhoid-, HPV-, tetanus- and diphtheria-specific antigens measured at two time points post vaccination. S. mansoni infection was determined as positive if either the plasma Circulating Anodic Antigen (CAA) assay or stool PCR were positive. Hookworm and Strongyloides were determined by stool PCR. Linear mixed effects regression was used to assess associations. Results: Among 478 adolescents, 70% were Schistosoma mansoni (Sm) infected and 23% hookworm infected at baseline. Sm was associated with lower Salmonella Typhi O:LPS-specific IgG responses (adjusted geometric mean ratio (aGMR) 0.69 (0.57-0.83)), and hookworm with higher diphtheria-specific IgG (aGMR 1.16 (1.02, 1.31)) and lower HPV-16-specific IgG (aGMR 0.70 (0.55, 0.90)) post-vaccination. High Sm intensity was associated with lower BCG-specific interferon-g and S. Typhi O:LPS-specific IgG. Conclusions: We found inverse associations between Sm and responses to two live vaccines, whereas hookworm was positively associated with diphtheriaspecific IgG. These findings support the hypothesis that helminth infections can modulate vaccine responses, while also highlighting potential heterogeneity in the direction of these effects. [ABSTRACT FROM AUTHOR]

Objectives: Parenting self-efficacy has been associated with positive parenting behaviors, fewer parental mental health problems, less family dysfunction, and better child development outcomes. The parenting sense of competence (PSOC) scale is commonly used to measure parenting self-efficacy in high-resource settings. This study sought to examine the factor structure, internal consistency, and convergent construct validity of the PSOC in a sample of predominantly HIV-infected women in Uganda. Methods: Using data from 155 HIV-affected caregivers who participated in a randomized controlled trial of a parenting intervention, two and three factor models of a 16-item translated version of the PSOC were tested using confirmatory factor analysis. Multivariable regression models were used to examine relationships between parenting confidence (operationalized using the best-fitting PSOC model), caregiver mental health symptoms (depression and anxiety), social support, family dysfunction, and family wealth, after adjusting for covariates. Results: Neither the two- nor three-factor models of the PSOC demonstrated adequate model fit; however, adequate model fit was demonstrated for a one-factor model that included only items from the PSOC efficacy subscale. Cronbach's alpha was 0.73 for this subscale. Correlates of parenting self-efficacy in this sample included caregiver depression, family dysfunction, and family wealth, but not caregiver anxiety or social support. Conclusions for Practice: These findings lend support for future use of the PSOC efficacy subscale among HIV-affected caregivers of children in low-resource settings such as rural Uganda. [ABSTRACT FROM AUTHOR]