The neutralization antibodies of SARS-CoV-2 during COVID-19 outbreak in Da Nang, Vietnam, July - August 2020

Beside molecular tests (realtime RT-PCR) which known as the golden key for SARS-CoV-2 confirmation, antibody test can be used to determine the responses in human antibody to SARS-CoV-2 and the result of plaque reduction neutralization test (PRNT) could identify the people who have been exposed with the SARS-CoV-2 and carried the neutralization antibody. Total 9936 samples were collected in 3 groups healthcare workers, inpatients (not related to COVID-19 before) and community in Da Nang city during July-August 2020. These cross sectional results showed that the rate of neutralization antibody in three groups in this research was 0.2%, in that, 0.1% in community, 0.2% in inpatient and 0.4% in healthcare workers. Follow-up study with 1253 paired sera of healthcare workers, the rate of SARS-CoV-2 neutralization antibody was determined as 2.1%. A downward trend of this neutralization antibody overtime has been shown in the study.