Modified ARCHITECT® serologic assays enable plasma-level performance from dried blood spot samples.

Dried blood spots (DBSs) provide an alternative sample input for serologic testing. We evaluated DBSs for the ARCHITECT® hepatitis B surface antigen (HBsAg) NEXT, hepatitis B e-antigen (HBeAg), anti-hepatitis B core antigen (anti-HBc II), HIV antigen/antibody (Ag/Ab) Combo and AdviseDx SARS-CoV-2 IgG II assays. Assay performance with DBSs was assessed with or without assay modification and compared with on-market assay with plasma samples. DBS stability was also determined. HBsAg NEXT and HIV Ag/Ab Combo assays using DBSs showed sensitivity and specificity comparable to that of on-market assays. Modified HBeAg, anti-HBc II and SARS-CoV-2 IgG II DBS assays achieved performance comparable to on-market assays. Use of DBSs as input for high-throughput serologic assays is expected to have significant implications for improving population surveillance and increasing access to diagnostic testing.

Trends in blood donations, blood donors' knowledge, practices and expectations during the COVID-19 pandemic in Cameroon.

INTRODUCTION: The COVID-19 pandemic, caused by a novel coronavirus, has already affected over 99 062 people in 53 African countries and killed 3082. The pandemic threatens blood supply but we do not yet know its impact on blood donations or on the perceptions and expectations of donors. METHODS: We conducted a cross-sectional study in four hospital-based blood services in Cameroon, using a survey design and focusing on the subjective and cultural aspects of donors. Using a semi-structured questionnaire, we collected the participants' responses as to their understanding of COVID-19 and of current protection measures, and their expectations. Data on trends of blood donations were collected retrospectively for the period from 1st January to 30th April 2019 and the same period in 2020. RESULTS: Of 494 donors included, 432 (87·4%) were enrolled from fixed blood collection sites and 62 (12·6%) were contacted by phone. A total of 464 (93·9%) participants believed that the COVID-19 is a lung disease, but some declared it to be imaginary (7·7%), a foreign disease (8·3%) or a blood-borne disease (3·2%). The participants reported that the distribution of face masks and hydroalcoholic solutions (92·5%), social distancing and hygiene (6·3%) are the most important measures that need to be in place for safe donation. The number of blood donations dropped by 21·5% between 2019 and 2020. CONCLUSION: Most of the donors know COVID-19, its transmission routes and manifestations. In the absence of barrier measures, they perceive blood donation as a threat to their health. Distribution of masks and hydroalcoholic solution might motivate more donors and improve the blood supply.