Seroprevalence of SARS COV-2 anti-nucleocapsid antibodies in Turkish healthcare workers before vaccination schedule: January 2021

Ayşin Kılınç Toker 1 * , Ayşe Turunç Özdemir 1, Duygu Çerçioğlu Özdemir 1, Esma Eryilmaz Eren 1, Esma Saatçi 2, İbrahim Toker 3, İlhami Çelik 1
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1 Department of Infectious Disease and Clinical Microbiology, Kayseri City Hospital, Kayseri, Turkey
2 Department of Medical Microbiology, Kayseri City Hospital, Kayseri, Turkey
3 Department of Emergency Medicine, Kayseri City Hospital, Kayseri, Turkey
* Corresponding Author
J CLIN MED KAZ, Volume 19, Issue 3, pp. 65-68.
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Objective: We aimed to assess the seroprevalence of SARS-CoV-2 infection and associated factors among Turkish HCWs, before the Covid-19 vaccination program in January 2021.
Material and methods: We performed antibody assessment against SARS-CoV-2 in blood samples from participants using the Elecsys® Anti-SARS-CoV-2 electrochemiluminescence immunoassay. Samples with a cut-off index (COI; signal sample/cut-off) <1.0 were considered negative, samples with ≥1.0 were deemed positive.
Results: 714 HCWs, 487 women (68.2%), were included in our study. The mean age of the participants was 35.9 ± 8.4 (min:18, max: 62). 370 (51.8%) HCWs's the antibody level was negative, and 344 (48.2%) was positive. While 47.1% (n=122) of the HCWs with positive RT-PCR were antibody positive, 48.8% (n=222) were negative. There was no statistically significant difference in mean age and age groups (p values ​​0.338 and 0.414, respectively). Also, there was no statistically significant difference in antibody levels by gender (p=0.236). There was no significant difference between antibody positivity according to the presence of comorbidity, and the risk area studied (p=0.556, p=0.335, respectively). There was a statistically significant difference between lung involvement and antibody positivity during Covid-19 infection (p= <0.001).
Conclusion: In our study, the seroprevalence of SARS-CoV-2 antibodies in HCWs was higher than the average population and approximately fifty percent. Multicenter studies with more HCWs would be helpful to determine overall seroprevalence rates.


Kılınç Toker A, Turunç Özdemir A, Çerçioğlu Özdemir D, Eryilmaz Eren E, Saatçi E, Toker İ, et al. Seroprevalence of SARS COV-2 anti-nucleocapsid antibodies in Turkish healthcare workers before vaccination schedule: January 2021. J CLIN MED KAZ. 2022;19(3):65-8.


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