Reality of COVID-19 Reinfection
Attapon Cheepsattayakorn and Ruangrong Cheepsattayakorn
Journal Title:Acta Scientific Microbiology
Generally, the immunity development that responds to a pathogenic microorganism occurs around 1 - 2 weeks with a non-specific innate response followed by body producing antibodies (humoral responses), immunoglobulins in combination with pro-duction of T-cells or cellular immunity. The virus in the body will be eliminated by this combined adaptive response. The definitive viral elimination by their protective role from viral reinfection is yet unidentified. Around eighty known distinct genotypical vari-ants of SARS-CoV-2 (COVID-19) have been identified. Several pre-vious studies demonstrated that SARs-CoV-2 (COVID-19) can per-sistently present in the feces of the patients, whereas no oral-fecal transmission markers were identified. A previous study in Beijing, China revealed that the virus can persist in the sputum for 39 days after becoming pharyngeal-swab negative. IgM-negative, IgG-positive antibody response and non-detectable viral ribonucleic acid (RNA) after discharging and consequent positive-SARS-CoV-2 (COVID-19)-RNA test, remained negative IgM, and positive IgG an-tibody tests was demonstrated in three readmitted asymptomatic-COVID-19 patients in Tongji Hospital, China. Due to the highest titers of SARS-CoV-2 RNA reaching within 7 - 10 days of clinical symptom onset and declining thereafter, the upper respiratory tract (posterior nasopharyngeal tonsil region) swabs should be performed.