HBV transfusion transmission from occult HBV infection carrying extremely low viral loads is related to plasma volume transfused and possibly prevented by anti-HBs. HBV blood safety could be further improved by either anti-HBc screening, HBV DNA NAT with a LOD of 0.8 copies/mL (0.15 IU/mL) or pathogen reduction of blood components.

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Rapid COVID-19 diagnosis in the hospital is essential, although this is complicated by 30%–50% of nose/throat swabs being negative by SARS-CoV-2 nucleic acid amplification testing (NAAT). Furthermore, the D614G spike mutant dominates the pandemic and it is unclear how serological tests designed to detect anti-spike antibodies perform against this variant. We assess the diagnostic accuracy of combined rapid antibody point of care (POC) and nucleic acid assays for suspected COVID-19 disease due to either wild-type or the D614G spike mutant SARS-CoV-2. The overall detection rate for COVID-19 is 79.2% (95% CI 57.8–92.9) by rapid NAAT alone. The combined point of care antibody test and rapid NAAT is not affected by D614G and results in very high sensitivity for COVID-19 diagnosis with very high specificity.

Summary There is an urgent need for rapid SARS-CoV-2 testing in hospitals to limit nosocomial spread. We report an evaluation of point of care (POC) nucleic acid amplification testing (NAAT) in 149 participants with parallel combined nasal and throat swabbing for POC versus standard lab RT-PCR testing. Median time to result is 2.6 (IQR 2.3–4.8) versus 26.4 h (IQR 21.4–31.4, p < 0.001), with 32 (21.5%) positive and 117 (78.5%) negative. Cohen’s κ correlation between tests is 0.96 (95% CI 0.91–1.00). When comparing nearly 1,000 tests pre- and post-implementation, the median time to definitive bed placement from admission is 23.4 (8.6-41.9) versus 17.1 h (9.0–28.8), p = 0.02. Mean length of stay on COVID-19 “holding” wards is 58.5 versus 29.9 h (p < 0.001). POC testing increases isolation room availability, avoids bed closures, allows discharge to care homes, and expedites access to hospital procedures. POC testing could mitigate the impact of COVID-19 on hospital systems.

Nucleic acid amplification for the detection of SARS-CoV-2 RNA in respiratory samples is the standard method for diagnosis. The majority of this testing is centralised and therefore turnaround times of several days. Point-of-care testing with rapid turnaround times would allow more effective triage in settings where patient management and infection control decisions need to be made rapidly. Inclusivity and specificity of the SAMBA II SARS-CoV-2 Test was determined by both in silico analyses of the primers and probes and wet testing. The SAMBA II SARS-CoV-2 Test was evaluated for performance characteristics. Clinical performance was evaluated in residual combined throat/nose swabs and compared to the Public Health England real-time PCR assay targeting the RdRp gene. The SAMBA II SARS-CoV-2 Test has an analytical sensitivity of 250 cp/mL detecting two regions of the genome (Orf1ab and N). The clinical performance was evaluated in 172 residual combined nose/throat swabs provided by the Clinical Microbiology and Public Health Laboratory, Addenbrooke's Hospital, Cambridge (CMPHL), which showed an estimated positive percent agreement of 98.9% (95% CI: 93.83-99.97) negative percent agreement of 96.4% (95%CI: 89.92-99.26) compared to testing by CMPHL. The data shows that the SAMBA II SARS-CoV-2 Test performs equivalently to the centralised testing methods with shorter turnaround time of 86-101 minutes). Point of care testing, such as SAMBA, should enable rapid patient management and effective implementation of infection control measures.