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Background> 94% of new annual leprosy cases are diagnosed in populations co-endemic for soil-transmitted helminths (STH). STH can profoundly dysregulate host immune responses towards Th2 bias, which can be restored over time after deworming. We hypothesize that STH co-infection is associated with leprosy reaction (denoted as simply “reaction” herein) occurrence within a co-endemic population.MethodsA cohort study was performed on a cohort of Nepalese leprosy patients across treatment and diagnostic classifications who were screened by routine fecal smear microscopy and multiplex quantitative PCR (qPCR) for Ascaris lumbricoides (Al), Strongyloides stercoralis (Ss), Ancyclostoma duodenale (Ad) and Necator americanus (Na).ResultsAmong 145 patients, 55% were positive for ≥ 1 STH (STH +): 34% Al +, 18% Ss +, 17% Ad + and 5% Na +. Significant inverse STH and reaction relationships were evidenced by the bulk of cases: 63% reaction-negative were STH + of total cases (p = 0.030) while 65% reaction-positive were STH − in new cases (96; p = 0.023). Strikingly, the majority of STH + were reaction-negative, even when considering each species: 59% Al +, 60% Ss +, 62% Ad + and 67% Na + of new leprosy cases.ConclusionsAbsence of STH co-infection is associated with leprosy reaction at diagnosis within a co-endemic population. This is likely due to immune reconstitution effects after deworming or interruption of chronic STH-mediated immune dysregulation.

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The corona virus disease -2019 (COVID-19) pandemic has caused a massive global public health havoc. Recent published clinical trials show conflicting data for use of chloroquine/hydroxychloroquine for COVID-19. This study meticulously evaluated the various dosages of chloroquine and hydroxychloroquine utilized in clinical trials registered in Chinese and US clinical trial registries for the treatment of pneumonia caused by SARS-CoV-2. Moreover, the results of published clinical trials and in vitro studies using chloroquine and hydroxychloroquine relevant to the disease are discussed.

Various reports of decreased analytical sensitivities of real-time PCR-based detection of Coronavirus Disease 2019 (COVID-19) have been associated with occurrence of mutations in the target area of primer/probe binding. Knowledge about propensities of different genes to undergo mutation can inform researchers to select optimal genes to target for the qPCR design. We analyzed supplementary data from over 45 thousand SARS-CoV-2 genomes provided by Mercatelli et al to calculate the unique and prevalent mutations in different genes of SARS-CoV-2. We found that non-structural proteins in the ORF1ab region were more conserved compared to structural genes. Further factors which need to be relied upon for proper selection of genes for qPCR design are discussed.

The genome sequence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been evolving via genomic drifts resulting in “emerging/drifting variants” circulating worldwide. The construction of polymerase chain reaction (PCR) assays for the reliable, efficient, and specific diagnosis of the drifting variants of SARS-CoV-2 is specifically governed by the selection and construction of primers and probes. The efficiency of molecular diagnosis is impacted by the identity/homology of the genome sequence of SARS-CoV-2 with other coronaviruses, drifting variants or variants of concern (VOCs) circulating in communities, inherent capacity of mutation(s) of various target genes of SARS-CoV-2, and concentration of genes of interest in host cells. The precise amplicon selection and construction of primers and probes for PCR-based assays can efficiently discriminate specific SARS-CoV-2 drifting variants. The construction of single nucleotide polymorphism (SNP)-specific primers and probes for PCR assays is pivotal to specifically distinguish SARS-CoV-2 variants present in the communities and contributes to better diagnosis and prevention of the ongoing COVID-19 pandemic. In this study, we have utilized in silico-based bioinformatic tools where the alignment for genes, the positions and types of SNPs/mutations of VOCs, and the relative number of SNPs per nucleotide in different genomic regions were investigated. Optimal and specific genome region (amplicon) selection with comparatively lower mutability in the SARS-CoV-2 genome should be prioritized to design/construct PCR assays for reliable and consistent diagnosis in various regions of the world for a longer duration of time. Further, the rational selection of target genes that is at an optimal detectable concentration in biological samples can bolster PCR assays of high analytical sensitivity. Hence, the construction of primers and probes with the rational selection of targeting specific E gene, genomic regions with highly conserved sequences, multiple target genes with relatively lower mutability and detectable level of concentration, SNP-specific binding regions of spike (S gene) protein, and shorter amplicon size (100–150 bp) are vital for the PCR assays to achieve optimal efficiency in the point-of-care laboratory diagnosis of circulating drifting variants of SARS-CoV-2 with optimal accuracy.

This meta-analysis was designed to assess the effect of the addition of a bead-beating (BB) step during DNA extraction to effectively isolate Trichuris trichiura DNA from stool samples for quantitative polymerase chain reaction (qPCR)-based diagnosis. qPCR-based molecular studies comparing the inclusion of a bead-beating step during the DNA extraction from stool samples with extraction without the step were included in the analysis. Studies using real patient samples in community settings were included. The PubMed database and Google search engine were searched in December 2019. Risk of bias and applicability were assessed using the Quality Assessment of Diagnostic Accuracy Studies-2 checklist. Odds ratios (ORs) for individual studies were combined to estimate the random effects model OR. A total of six independent sub-studies were gathered from two published original articles. The division of the two major studies into six sub-studies was indispensable due to the nature of the study carried out. 128 of the total 192 samples (in all studies) were positive for T. trichiura when BB was used during DNA extraction compared to 108/192 when BB was excluded. The combined OR was 1.66 (95% confidence interval: 1.059 to 2.602). Though only two articles were included in the study, six exclusive individual sub-studies were analyzed. Inherent differences in the background prevalence of helminths in the study population could impact the sensitivity of qPCR. It was found that the inclusion of the BB step during DNA extraction significantly increased the sensitivity of the test. This study was not registered in any database.

Ovarian cancer is a gynecological cancer of high mortality rate. Most of the ovarian cancer origin from the surface epithelium of the ovaries. Ovarian cancers gain metastatic and