The effect of COVID certificates on vaccine uptake, health outcomes, and the economy (preprint)

In the COVID-19 pandemic, governments have, among other measures, 1,2 mandated the use of COVID certificates to prove vaccination, recovery, or a recent negative test, and have required them to access shops, restaurants, schools, universities, or workplaces. 3 While arguments for and against COVID certificates have focused on reducing transmission and ethical concerns, 4,5 the incentive effect of COVID certificates on vaccine uptake, health outcomes, and the economy has not yet been investigated. To estimate this effect, we construct counterfactuals based on innovation diffusion theory 6 for France, Germany, and Italy. We estimate that the announcement of COVID certificates during summer 2021 led to increased vaccine uptake in France of 13.0 (95% CI 9.7–14.9) percentage points (p.p.) of the total population up to the end of the year, in Germany 6.2 (2.6–6.9) p.p., and in Italy 9.7 (5.4–12.3) p.p. Further, this averted an additional 3,979 (3,453–4,298) deaths in France, 1,133 (-312–1,358) in Germany, and 1,331 (502–1,794) in Italy; and prevented gross domestic product (GDP) losses of €6.0 (5.9–6.1) billion in France, €1.4 (1.3–1.5) billion in Germany, and €2.1 (2.0–2.2) billion in Italy. Notably, the application of COVID certificates substantially reduced the pressure on intensive care units (ICUs) and, in France, averted occupancy levels being exceeded where prior lockdowns were instated. Varying government communication efforts and restrictions associated with COVID certificates may explain country differences, such as the smaller effect in Germany. Overall, our findings are more sizeable than predicted. 7 This analysis may help inform decisions about when and how to employ COVID certificates to increase vaccine uptake and thus avoid stringent interventions, such as closures, curfews, and lockdowns, with major social and economic consequences.

Detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in a fourplex real-time quantitative reverse transcription-PCR assays. (preprint)

The early diagnosis of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections is required to identify and isolate contagious patients to prevent further transmission of the coronavirus disease 2019 (COVID-19). In this study, we present a multitarget real-time TaqMan reverse transcription PCR (rRT-PCR) assay for the quantitative detection of SARS-CoV-2 and some of its circulating variants harboring mutations that give SARS-CoV-2 a selective advantage. Seven different primer-probe sets that included probes containing locked nucleic acid (LNA) nucleotides were designed to amplify specific wild-type and mutant sequences in Orf1ab, Envelope (E), Spike (S), and Nucleocapsid (N) genes. Furthermore, a newly developed primer-probe set targeted human beta-2 microglobulin (B2M) as a highly sensitive internal control for RT efficacy. All singleplex and fourplex assays detected less than or equal to 14 copies/reaction of quantified synthetic RNA transcripts, with a linear amplification range of 9 logarithmic orders. Primer-probe sets for detection of SARS-CoV-2 exhibited no false-positive amplifications with other common respiratory pathogens, including human coronaviruses NL63, 229E, OC43, and HKU-1. Given the emergence of SARS-CoV-2 variants and their rapid spread in some populations, fourplex rRT-PCR assay containing four primer-probe sets represents a reliable approach to detect multiple viral target sequences containing typical mutations of SARS-CoV-2 variants in a single reaction, allowing quicker detection of circulating relevant variants.