The Role of Preventive Measures or a Previously Immunized Population: A Pilot Study on Coronavirus Disease-19 in Syria

Background: A recent ongoing pandemic of coronavirus disease named coronavirus disease 2019 (COVID-19) has spread in Syria from March 2020 with a pattern of a slow case increase. So far, the government has put the country under lock-down orders as a preventive measure. However, there is a considerable belief in the medical community of our country supposes that the virus has previously passed through the country depending on the high numbers of diagnosed severe respiratory infections early in 2020. Thus, this study was designed to determine the number of people with detectable antibodies to SARS-CoV-2 from two samples of healthy adults with and without a previous history of severe respiratory infection in the last 6 months of the study. Materials and Methods: To this end, samples were collected from 123 and 198 subjects with a previous severe respiratory infection and healthy controls, respectively. Then, immunoglobulin M (IgM) and IgG anti-SARS-CoV-2 antibodies were tested as well. Results: None of the samples from both groups tested IgG positive in the assay while four tested IgM samples were positive. Accordingly, these positive samples were re-analyzed and remained IgM positive in the second test although the reverse transcriptase-polymerase chain reaction for the SARS-CoV-2 virus was negative. Conclusion: Based on our findings, there is no evidence concerning the previous COVID-19 infection in Syria thus it is suggested that all isolation and lock-down orders should be respected as an effective preventive tool in this regard.