The Strongyloides stercoralis-hookworms association as a path to the estimation of the global burden of strongyloidiasis: A systematic review

Soil-transmitted helminths (STH) represent a significant public health problem. However, Strongyloides stercoralis is not yet integrated into the control strategy against STH, given limi- tations to accurately assess its burden. Considering that S. stercoralis shares biological and epidemiological characteristics with hookworms, we describe a new approach for an improved estimation of the burden of infections by S. stercoralis based on the prevalence and burden of hookworms and the relationship between these species. A systematic review of publications reporting prevalence rates for S. stercoralis and hookworms was carried out. The data was classified into two categories: 1) “Community”, with surveys including all age groups, and 2) “SAC”, with surveys limited to school-aged children. The relationship between S. stercoralis and hookworms was characterized in order to estimate the global burden of S. stercoralis infections. The study is registered in PROSPERO (CRD42019131127). Spearman correlation coefficient between S. stercoralis and hookworms was estimated and the global burden of S. stercoralis infections was estimated using a regression model. A total of 119 articles were included, and a significant positive correlation between the burden of S. stercoralis and hook- worms was identified. Spearman’s coefficient for Community surveys was 0.94 and for SAC surveys it was 0.63. Based on the linear model, the global burden of S. stercoralis infections was estimated at 386 million (95%CI 324–449 million) people, including 22 million (95%CI 20–24 million) SAC. The significant relationship between S. stercoralis and hookworms allows an estimation of the global burden of S. stercoralis infections in most epidemiologic settings using hookworm burden and justifies the search of integrated control activities

Effect of Cr(V) on reproductive organ morphology and sperm parameters: An experimental study in mice

BACKGROUND: Cr(V) species are formed during the intracellular reduction of Cr(VI), a ubiquitous environmental pollutant. In this study, the acute toxicity of a physiologically stable Cr(V) compound, [Cr(V)-BT](2- )(BT = bis(hydroxyethyl)aminotris(hydroxymethyl)methane) was investigated in the male reproductive system of sexually mature 60-day-old male ICR-CD1 mice. METHODS: Eight-week-old animals were subcutaneously injected daily with a dose of ca 8 μmol of Cr/mouse, during 5 days. The control group was injected with 0.5 mL of BT buffer. Testis and epididymis morphology was evaluated using light and transmission electron microscopy. Epididymal sperm counts, motility and acrosome integrity were also assayed using standard methods. RESULTS: Seminiferous epithelium abnormalities were detected in the Cr(V)-BT experimental group, including intraepithelial vacuolation, and remarkable degeneration of Sertoli cells, spermatocytes and spermatids. The premature release of germ cells into the tubular lumen was also evident. Histological evaluation of epididymal compartments revealed apparently normal features. However, the epididymal epithelium presented vacuolation. [Cr(V)-BT](2- )induced a reduction in sperm acrosome integrity. However, sperm motility and density were not significantly affected. CONCLUSION: This in vivo study using a Cr(V) compound, provides evidence for the potential reproductive hazards caused on male reproductive system by species containing chromium in intermediate oxidation states

Assessment of Diet-Related Changes on Albendazole Absorption, Systemic Exposure, and Pattern of Urinary Excretion in Treated Human Volunteers

Soil-transmitted-helminth (STH) infections are a persistent global public health problem. Control strategies for STH have been based on the use of mass drug administration (MDA) mainly targeting preschool- and school-aged-children, although there is increasing interest in expanding treatment to include adults and others through community-wide MDA. Coverage assessment is critical to understanding the real effectiveness of albendazole (ALB) treatment in those MDA programs.</jats:p

Linear regression.

Blue dots represent surveys with diagnostic methods of high sensitivity (Hight-S) and purple dots represent surveys with diagnostic methods of low sensitivity (Low-S). a. Community surveys. The black line represents the curve of equation 1 (Table 1), for the linear regression of all surveys (Hight-S and Low-S) of the Community population. The blue line represents the curve of equation 2 (Table 1), for the linear regression of all surveys of the Community population with Hight-S. b. School-aged children (SAC) surveys. The black line represents the curve of equation 3 (Table 1), for the linear regression of all surveys (Hight-S and Low-S) of the SAC population. The blue line represents the curve of equation 4 (Table 1), for the linear regression of all surveys of the SAC population with Hight-S. Gray shading represents the 95% confidence interval.</p

Number of surveys per year.

Orange bars represent the number of surveys in school-aged children (SAC) population. Green bars represent the number of surveys of the Community population. The blue line represents the total number of surveys with highly sensitive diagnostic methods (High-S).</p

PRISMA (preferred reporting items for systematic reviews and meta-analyses) flow diagram of systematic literature search.

PRISMA (preferred reporting items for systematic reviews and meta-analyses) flow diagram of systematic literature search.</p

Linear equations for the different populations.

The total and school-aged children (SAC) population infected with hookworms and the proportion of SAC in each region were obtained from References 12 and 21. St: Strongyloides stercoralis, HKW: hookworm, Com_burden: Community burden, SAC_burden: SAC burden, High-S: high sensitivity methods, 95%CI: 95% confidence interval.</p