tetano
Editor, Senior Moderator
Pathogens
. 2021 Jun 20;10(6):774.
doi: 10.3390/pathogens10060774.
SARS-CoV-2 Seroprevalence and Neutralizing Antibody Response after the First and Second COVID-19 Pandemic Wave in Croatia
Tatjana Vilibic-Cavlek[SUP] 1 2 [/SUP], Vladimir Stevanovic[SUP] 3 [/SUP], Maja Ilic[SUP] 4 [/SUP], Ljubo Barbic[SUP] 3 [/SUP], Krunoslav Capak[SUP] 5 [/SUP], Irena Tabain[SUP] 1 [/SUP], Jasna Lenicek Krleza[SUP] 6 [/SUP], Thomas Ferenc[SUP] 7 [/SUP], Zeljka Hruskar[SUP] 1 [/SUP], Renata Zrinski Topic[SUP] 6 [/SUP], Vanja Kaliterna[SUP] 8 [/SUP], Arlen Antolovic-Pozgain[SUP] 9 [/SUP], Jasmina Kucinar[SUP] 10 [/SUP], Iva Koscak[SUP] 11 [/SUP], Dijana Mayer[SUP] 12 [/SUP], Mario Sviben[SUP] 2 13 [/SUP], Ljiljana Antolasic[SUP] 1 [/SUP], Ljiljana Milasincic[SUP] 1 [/SUP], Lovro Bucic[SUP] 4 [/SUP], Ivana Ferencak[SUP] 1 [/SUP], Bernard Kaic[SUP] 4 [/SUP]
Affiliations
Abstract
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a novel coronavirus with a pandemic spread. So far, a total of 349,910 SARS-CoV-2 cases and 7687 deaths were reported in Croatia. We analyzed the seroprevalence and neutralizing (NT) antibody response in the Croatian general population after the first (May-July 2020) and second (December 2020-February 2021) pandemic wave. Initial serological testing was performed using a commercial ELISA, with confirmation of reactive samples by a virus neutralization test (VNT). A significant difference in the overall seroprevalence rate was found after the first (ELISA 2.2%, VNT 0.2%) and second waves (ELISA 25.1%, VNT 18.7%). Seropositive individuals were detected in all age groups, with significant differences according to age. The lowest prevalence of NT antibodies was documented in the youngest (<10 years; 16.1%) and the oldest (60-69/70+ years; 16.0% and 12.8%, respectively) age groups. However, these age groups showed the highest median NT titers (32-64). In other groups, seropositivity varied from 19.3% to 21.5%. A significant weak positive correlation between binding antibody level as detected by ELISA and VNT titer (rho = 0.439, p < 0.001) was observed. SARS-CoV-2 NT antibody titers seem to be age-related, with the highest NT activity in children under 10 years and individuals above 50 years.
Keywords: COVID-19; Croatia; ELISA; SARS-CoV-2; VNT; seroprevalence.
. 2021 Jun 20;10(6):774.
doi: 10.3390/pathogens10060774.
SARS-CoV-2 Seroprevalence and Neutralizing Antibody Response after the First and Second COVID-19 Pandemic Wave in Croatia
Tatjana Vilibic-Cavlek[SUP] 1 2 [/SUP], Vladimir Stevanovic[SUP] 3 [/SUP], Maja Ilic[SUP] 4 [/SUP], Ljubo Barbic[SUP] 3 [/SUP], Krunoslav Capak[SUP] 5 [/SUP], Irena Tabain[SUP] 1 [/SUP], Jasna Lenicek Krleza[SUP] 6 [/SUP], Thomas Ferenc[SUP] 7 [/SUP], Zeljka Hruskar[SUP] 1 [/SUP], Renata Zrinski Topic[SUP] 6 [/SUP], Vanja Kaliterna[SUP] 8 [/SUP], Arlen Antolovic-Pozgain[SUP] 9 [/SUP], Jasmina Kucinar[SUP] 10 [/SUP], Iva Koscak[SUP] 11 [/SUP], Dijana Mayer[SUP] 12 [/SUP], Mario Sviben[SUP] 2 13 [/SUP], Ljiljana Antolasic[SUP] 1 [/SUP], Ljiljana Milasincic[SUP] 1 [/SUP], Lovro Bucic[SUP] 4 [/SUP], Ivana Ferencak[SUP] 1 [/SUP], Bernard Kaic[SUP] 4 [/SUP]
Affiliations
- PMID: 34203060
- DOI: 10.3390/pathogens10060774
Abstract
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a novel coronavirus with a pandemic spread. So far, a total of 349,910 SARS-CoV-2 cases and 7687 deaths were reported in Croatia. We analyzed the seroprevalence and neutralizing (NT) antibody response in the Croatian general population after the first (May-July 2020) and second (December 2020-February 2021) pandemic wave. Initial serological testing was performed using a commercial ELISA, with confirmation of reactive samples by a virus neutralization test (VNT). A significant difference in the overall seroprevalence rate was found after the first (ELISA 2.2%, VNT 0.2%) and second waves (ELISA 25.1%, VNT 18.7%). Seropositive individuals were detected in all age groups, with significant differences according to age. The lowest prevalence of NT antibodies was documented in the youngest (<10 years; 16.1%) and the oldest (60-69/70+ years; 16.0% and 12.8%, respectively) age groups. However, these age groups showed the highest median NT titers (32-64). In other groups, seropositivity varied from 19.3% to 21.5%. A significant weak positive correlation between binding antibody level as detected by ELISA and VNT titer (rho = 0.439, p < 0.001) was observed. SARS-CoV-2 NT antibody titers seem to be age-related, with the highest NT activity in children under 10 years and individuals above 50 years.
Keywords: COVID-19; Croatia; ELISA; SARS-CoV-2; VNT; seroprevalence.