Tags

Type your tag names separated by a space and hit enter

COVID-19 and lombardy: TESTing the impact of the first wave of the pandemic.
EBioMedicine. 2020 Nov; 61:103069.E

Abstract

BACKGROUND

Italy was the first western country to experience a large Coronavirus Disease 2019 (COVID-19) outbreak and the province of Bergamo experienced one of the deadliest COVID-19 outbreaks in the world. Following the peak of the epidemic in mid-March, the curve has slowly fallen thanks to the strict lockdown imposed by the Italian government on 9th March 2020.

METHODS

We performed a cross-sectional study to assess the prevalence of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection in 423 workers in Bergamo province who returned to the workplace after the end of the Italian lockdown on 5th May 2020. To this end, we performed an enzyme-linked immunosorbent assay (ELISA) to detect the humoral response against SARS-CoV-2 and a nasopharyngeal swab to assess the presence of SARS-CoV-2 RNA by real-time reverse transcription polymerase chain reaction (rRT-PCR). As a secondary aim of the study, we validated a lateral flow immunochromatography assay (LFIA) for the detection of anti-SARS-CoV-2 antibodies.

FINDINGS

ELISA identified 38.5% positive subjects, of whom 51.5% were positive for both IgG and IgM, 47.3% were positive only for IgG, but only 1.2% were positive for IgM alone. Only 23 (5.4%) participants tested positive for SARS-CoV-2 by rRT-PCR, although with high cycle thresholds (between 34 and 39), indicating a very low residual viral load that was not able to infect cultured cells. All these rRT-PCR positive subjects had already experienced seroconversion. When the ELISA was used as the comparator, the estimated specificity and sensitivity of the rapid LFIA for IgG were 98% and 92%, respectively.

INTERPRETATION

the prevalence of SARS-CoV-2 infection in the province of Bergamo reached 38.5%, significantly higher than has been reported for most other regions worldwide. Few nasopharyngeal swabs tested positive in fully recovered subjects, though with a very low SARS-CoV-2 viral load, with implications for infectivity and discharge policies for positive individuals in the post-pandemic period. The rapid LFIA used in this study is a valuable tool for rapid serologic surveillance of COVID-19 for population studies.

FUNDING

The study was supported by Regione Lombardia, Milano Serravalle - Milano Tangenziali S.p.A., Brembo S.p.A, and by MEI System.

Authors+Show Affiliations

Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Bergamo, Italy.Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Bergamo, Italy.Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Bergamo, Italy.Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Bergamo, Italy.Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Bergamo, Italy.Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Bergamo, Italy; Department of Biomedical and Clinical Sciences, University of Milan, Milan, Italy. Electronic address: giuseppe.remuzzi@marionegri.it.Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Bergamo, Italy.

Pub Type(s)

Journal Article

Language

eng

PubMed ID

33130396

Citation

Perico, Luca, et al. "COVID-19 and Lombardy: TESTing the Impact of the First Wave of the Pandemic." EBioMedicine, vol. 61, 2020, p. 103069.
Perico L, Tomasoni S, Peracchi T, et al. COVID-19 and lombardy: TESTing the impact of the first wave of the pandemic. EBioMedicine. 2020;61:103069.
Perico, L., Tomasoni, S., Peracchi, T., Perna, A., Pezzotta, A., Remuzzi, G., & Benigni, A. (2020). COVID-19 and lombardy: TESTing the impact of the first wave of the pandemic. EBioMedicine, 61, 103069. https://doi.org/10.1016/j.ebiom.2020.103069
Perico L, et al. COVID-19 and Lombardy: TESTing the Impact of the First Wave of the Pandemic. EBioMedicine. 2020;61:103069. PubMed PMID: 33130396.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - COVID-19 and lombardy: TESTing the impact of the first wave of the pandemic. AU - Perico,Luca, AU - Tomasoni,Susanna, AU - Peracchi,Tobia, AU - Perna,Annalisa, AU - Pezzotta,Anna, AU - Remuzzi,Giuseppe, AU - Benigni,Ariela, Y1 - 2020/10/22/ PY - 2020/07/24/received PY - 2020/09/25/revised PY - 2020/09/28/accepted PY - 2020/11/2/pubmed PY - 2020/11/26/medline PY - 2020/11/1/entrez KW - Coronavirus disease 2019 (COVID-19) KW - Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) KW - antibody response KW - enzyme-linked immunosorbent assay (ELISA) KW - epidemiological screening KW - lateral flow immunochromatography (LFIA) SP - 103069 EP - 103069 JF - EBioMedicine JO - EBioMedicine VL - 61 N2 - BACKGROUND: Italy was the first western country to experience a large Coronavirus Disease 2019 (COVID-19) outbreak and the province of Bergamo experienced one of the deadliest COVID-19 outbreaks in the world. Following the peak of the epidemic in mid-March, the curve has slowly fallen thanks to the strict lockdown imposed by the Italian government on 9th March 2020. METHODS: We performed a cross-sectional study to assess the prevalence of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection in 423 workers in Bergamo province who returned to the workplace after the end of the Italian lockdown on 5th May 2020. To this end, we performed an enzyme-linked immunosorbent assay (ELISA) to detect the humoral response against SARS-CoV-2 and a nasopharyngeal swab to assess the presence of SARS-CoV-2 RNA by real-time reverse transcription polymerase chain reaction (rRT-PCR). As a secondary aim of the study, we validated a lateral flow immunochromatography assay (LFIA) for the detection of anti-SARS-CoV-2 antibodies. FINDINGS: ELISA identified 38.5% positive subjects, of whom 51.5% were positive for both IgG and IgM, 47.3% were positive only for IgG, but only 1.2% were positive for IgM alone. Only 23 (5.4%) participants tested positive for SARS-CoV-2 by rRT-PCR, although with high cycle thresholds (between 34 and 39), indicating a very low residual viral load that was not able to infect cultured cells. All these rRT-PCR positive subjects had already experienced seroconversion. When the ELISA was used as the comparator, the estimated specificity and sensitivity of the rapid LFIA for IgG were 98% and 92%, respectively. INTERPRETATION: the prevalence of SARS-CoV-2 infection in the province of Bergamo reached 38.5%, significantly higher than has been reported for most other regions worldwide. Few nasopharyngeal swabs tested positive in fully recovered subjects, though with a very low SARS-CoV-2 viral load, with implications for infectivity and discharge policies for positive individuals in the post-pandemic period. The rapid LFIA used in this study is a valuable tool for rapid serologic surveillance of COVID-19 for population studies. FUNDING: The study was supported by Regione Lombardia, Milano Serravalle - Milano Tangenziali S.p.A., Brembo S.p.A, and by MEI System. SN - 2352-3964 UR - https://www.unboundmedicine.com/medline/citation/33130396/COVID_19_and_lombardy:_TESTing_the_impact_of_the_first_wave_of_the_pandemic_ L2 - https://linkinghub.elsevier.com/retrieve/pii/S2352-3964(20)30445-X DB - PRIME DP - Unbound Medicine ER -