key: cord-0780135-ebyav99w
authors: Riccò, Matteo; Ranzieri, Silvia; Marchesi, Federico
title: Rapid antigen tests for large-scale diagnostic campaigns: A case study from North-Eastern Italy
date: 2021-01-19
journal: J Infect
DOI: 10.1016/j.jinf.2021.01.011
sha: 4baf10fedd4fd847ca5a26e475d30f3e98141acd
doc_id: 780135
cord_uid: ebyav99w

nan

As pointed out by Alemany et al. in their recent report "Analytical and clinical performance of the panbio COVID-19 antigen detecting rapid diagnostic test" , rapid antigen diagnostic (RAD) tests may be instrumental for scaling up our diagnostic capacity. 1 , 2 Unfortunately, some field reports suggest that their real-world sensitivity may not exceed 70%, eliciting some concerns on their use for largescale testing campaigns. 3 In this regard, a mass-scale testing campaign was performed by means of RAD tests in the Italian province of South Tyrol, and respective open data have been made available by local authorities, allowing their third-party analysis. 4 , 5 For instance, during November 2020, Italian province of South Tyrol experienced a surge of daily notification rates for SARS-CoV-2 cases (i.e. 7-days moving average of 103.4/10 0,0 0 0 inhabitants, 95%CI 95.4-111.4 for the time period 1/11/2020 to 20/11/2020), that substantially doubled those of the bordering Italian region of Trentino (i.e. 42.8/10 0,0 0 0 inhabitants, 95%CI 42.8-44.6), and the Austrian State of Tyrol (i.e. 40.1/10 0,0 0 0 inhabitants, 95%CI 38.0-42.2). Trentino, Tyrol and South Tyrol are of similar size, comparable populations density, sharing significant cultural and environmental features. However, during the ongoing SARS-CoV-2 pandemic, such areas have been characterized by heterogenous approaches to the public health measures, both in terms of actual interventions and their timing.

In order to cope with frightening notification rates, local authorities from South Tyrol implemented a voluntary large-scale screening campaign based on RAD tests for SARS-CoV-2, that in 3 days (20/11/2020-22/11/2020) involved a total of 361,781 people (67.9% of the total population). 6 As shown in Fig. 1 , 7-days average of daily notification rates dropped from 110.9 (20/11/2020) to 31.5 cases/10 0,0 0 0 inhabitants (23/12/2020), being afterwards comparable to those of Trentino (in average: 34.5/10 0,0 0 0, 95%CI 32.0-36.9 for South Tyrol, vs. 35.0 95%CI 33.1-37.0, for Trentino), but still higher than those of Tyrol (10.5/10 0,0 0 0 inhabitants, 95%CI 9.7-11.2), seemly suggesting the substantial efficacy of this intervention.

However, after daily rates were percent normalized to their respective maximum values in order to cope with the different diagnostic strategies, epidemic curves of the three regions substantially overlapped until the end of December 2020, as sharing a common trend ( Fig. 2 ).

More precisely, normalized rates were similar in the 14 days following the mass screening test in South Tyrol (i.e. 78.9%, 95%CI 73.2-84.7 for South Tyrol; 81.5%, 95%CI 77.7-85.2 for Trentino; 76.6%, 95%CI 71.2-82.0 for Tyrol, ANOVA p value = 0.285), and they remained well correlated across all the assessed timeframe (i.e. Fig. 1 . Daily notification rates (7-days moving average) for the Italian Autonomous Provinces of Trento and South Tyrol, and for the Austrian State of Tyrol. Dotted lines represent the days of mass testing (i.e. 20/11/2020 to 22/11/2020) and the 14th day after the conclusion of the mass testing. All data were retrieved from official open data repositories (i.e. https://github.com/pcm-dpc/COVID-19 and https://www.data. gv.at/covid-19/ .

Daily notification normalized by maximum percent value for the Italian Autonomous Provinces of Trento and South Tyrol, and for the Austrian State of Tyrol. Dotted lines represent the days of mass testing (i.e. 20/11/2020 to 22/11/2020) and the 14th day after the conclusion of the mass testing. All data were retrieved from official open data repositories (i.e. https://github.com/pcm-dpc/COVID-19 and https://www.data.gv.at/covid-19/ . r = 0.818, p < 0.001 for South-Tyrol vs. Trentino, and 0.973, p < 0.001 for South Tyrol vs. Tyrol).

In summary, available estimates cannot confirm the unambiguous effect of the large-scale screening intervention on the

Analytical and clinical performance of the PANBIO Covid-19 antigen-detecting rapid diagnostic test

Urgent need of rapid tests for SARS CoV-2 antigen detection: evaluation of the SD-biosensor antigen test for SARS-CoV-2

Evaluation of a rapid diagnostic assay for detection of SARS-CoV-2 antigen in nasopharyngeal swabs sidonie

Bundesministerium für digitalisierung und wirtschaftsstandort -österreichisches COVID-19 open data informationsportal

An overview of the rapid test situation for COVID-19 diagnosis in the