Development and validation of a microarray for the confirmation and typing of norovirus RT-PCR products

Noroviruses are implicated in many worldwide institutional, food and waterborne outbreaks each year. Genetic typing of isolates is valuable for monitoring outbreak spread as well as variation in circulating strains. Microarrays have the potential to provide rapid genotype information for norovirus samples. The NoroChip v3.0 provides an oligonucleotide hybridization platform to screen for over 600 potential interactions in each experiment. The NoroChip v3.0 was developed at Health Canada and validated in seven international partner laboratories. Each laboratory validated the NoroChip v3.0 using norovirus amplicons routinely characterized in their testing protocols. Fragments from the capsid region (region C) and a 2.4 kb amplicon spanning polymerase and capsid sequences (region AD) were validated in six of the partner laboratories and provided correct genogroup typing information (GI or GII) when hybridized to the NoroChip v3.0. Results indicate that the current limiting factor for implementing the NoroChip v3.0 as a strain typing tool is the difficulty obtaining a long, specific amplicon from all circulating norovirus strains. Data obtained with the longer region AD amplicon provided the best discrimination between norovirus strains.     

Association between fear of stigma, depressive and anxiety symptoms in patients with somatoform pain disorder

Objectives: There is still poor acceptance for pain without somatic causes, and patients with somatoform pain disorder carry a stigma per se. The aim of this study was to identify predictors of fear of stigma including depression, anxiety and somatisation among patients with somatoform pain disorder.Methods: 132 patients with somatoform pain disorder were investigated by using the Link Stigma Questionnaire, the Beck Depression Inventory, the State-Trait Anxiety Inventory, the Whiteley-Index, and the Checklist for Somatisation.Results: Multiple linear regression analysis showed a significant positive association between fear of stigma and symptoms of depression and a negative association with patients' age.Conclusions: This is one of the first studies investigating this question among patients with somatoform pain disorder. Findings might indicate the importance of depressive symptoms for developing fear of stigma.     

Evolution of seroprevalence to SARS-CoV-2 in blood donors in Sarajevo Canton,Federation of Bosnia and Herzegovina: Cross-sectional and longitudinal studies

Background

Sarajevo Canton in the Federation of Bosnia and Herzegovina has recorded several waves of high SARS-CoV-2 transmission and has struggled to reach adequate vaccination coverage. We describe the evolution of infection- and vaccine-induced SARS-CoV-2 antibody response and persistence.

Methods

We conducted repeated cross-sectional analyses of blood donors aged 18–65 years in Sarajevo Canton in November–December 2020 and 2021. We analyzed serum samples for anti-nucleocapsid (anti-N) and anti-spike (anti-S) antibodies. To assess immune durability, we conducted longitudinal analyses of seropositive participants at 6 and 12 months.

Results

One thousand fifteen participants were included in Phase 1 (November–December 2020) and 1152 in Phase 2 (November–December 2021). Seroprevalence increased significantly from 19.2% (95% CI: 17.2%–21.4%) in Phase 1 to 91.6% (95% CI: 89.8%–93.1%) in Phase 2. Anti-S IgG titers were significantly higher among vaccinated (58.5%) than unvaccinated infected participants across vaccine products (p < 0.001), though highest among those who received an mRNA vaccine. At 6 months, 78/82 (95.1%) participants maintained anti-spike seropositivity; at 12 months, 58/58 (100.0%) participants were seropositive, and 33 (56.9%) had completed the primary vaccine series within 6 months. Among 11 unvaccinated participants who were not re-infected at 12 months, anti-S IgG declined from median 770.1 (IQR 615.0–1321.7) to 290.8 (IQR 175.7–400.3). Anti-N IgG antibodies waned earlier, from 35.4% seropositive at 6 months to 24.1% at 12 months.

Conclusions

SARS-CoV-2 seroprevalence increased significantly over 12 months from end of 2020 to end of 2021. Although individuals with previous infection may have residual protection, COVID-19 vaccination is vital to strengthening population immunity.