Objective: The protection from SARS-CoV-2 infection induced by SARS-CoV-2 anti-S1 and anti-S2 IgG antibody positivity resulting from natural infection was evaluated. Methods: The frequency of SARS-CoV-2 infection (as determined by virus RNA detection) was evaluated in a group of 1,460 seropositive and a control group of 8,150 seronegative healthcare workers in three Centres of Northern Italy in the period June-November 2020. Neutralizing serum titers were analyzed in seropositive subjects with or without secondary SARS-CoV-2 infection. Results: During the 6-month survey, 1.78% seropositive subjects developed secondary SARS-CoV-2 infection while 6.63% seronegative controls developed primary infection (odds ratio: 0.26; 95% confidence interval: 0.17-0.38). Secondary infection was associated with low or absent serum neutralizing titer (p<0.01) and was mildly symptomatic in 45.8% cases vs 71.4% symptomatic primary infections (odds ratio: 0.34; 95% confidence interval: 0.16-0.78). Conclusions: Immunity from natural infection appears protective from secondary infection; therefore, vaccination of seronegative subjects might be prioritized.

Rovida, F., Cassaniti, I., Percivalle, E., Sarasini, A., Paolucci, S., Klersy, C., et al. (2021). Incidence of SARS-CoV-2 infection in health care workers from Northern Italy based on antibody status: immune protection from secondary infection- A retrospective observational case-control study. INTERNATIONAL JOURNAL OF INFECTIOUS DISEASES, 109(August 2021), 199-202 [10.1016/j.ijid.2021.07.003].

Incidence of SARS-CoV-2 infection in health care workers from Northern Italy based on antibody status: immune protection from secondary infection- A retrospective observational case-control study

Luzzaro, Francesco
Membro del Collaboration Group
;
De Vito, Giovanni
Membro del Collaboration Group
;
2021

Abstract

Objective: The protection from SARS-CoV-2 infection induced by SARS-CoV-2 anti-S1 and anti-S2 IgG antibody positivity resulting from natural infection was evaluated. Methods: The frequency of SARS-CoV-2 infection (as determined by virus RNA detection) was evaluated in a group of 1,460 seropositive and a control group of 8,150 seronegative healthcare workers in three Centres of Northern Italy in the period June-November 2020. Neutralizing serum titers were analyzed in seropositive subjects with or without secondary SARS-CoV-2 infection. Results: During the 6-month survey, 1.78% seropositive subjects developed secondary SARS-CoV-2 infection while 6.63% seronegative controls developed primary infection (odds ratio: 0.26; 95% confidence interval: 0.17-0.38). Secondary infection was associated with low or absent serum neutralizing titer (p<0.01) and was mildly symptomatic in 45.8% cases vs 71.4% symptomatic primary infections (odds ratio: 0.34; 95% confidence interval: 0.16-0.78). Conclusions: Immunity from natural infection appears protective from secondary infection; therefore, vaccination of seronegative subjects might be prioritized.
Articolo in rivista - Articolo scientifico
immune protection; neutralizing antibody; SARS-CoV-2 infection; secondary infection;
English
7-lug-2021
2021
109
August 2021
199
202
none
Rovida, F., Cassaniti, I., Percivalle, E., Sarasini, A., Paolucci, S., Klersy, C., et al. (2021). Incidence of SARS-CoV-2 infection in health care workers from Northern Italy based on antibody status: immune protection from secondary infection- A retrospective observational case-control study. INTERNATIONAL JOURNAL OF INFECTIOUS DISEASES, 109(August 2021), 199-202 [10.1016/j.ijid.2021.07.003].
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Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/10281/321635
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