COVID-19 Medical Staff: "Re-positivity Due to Non-infectious Viral Fragments" (Update)

On the morning of the 29th, Oh Myung-don, Chair of the Central Clinical Committee for Emerging Infectious Diseases, is presenting data at a press conference held at the National Medical Center in Jung-gu, Seoul.

[Asia Economy Reporters Choi Dae-yeol and Kim Heung-soon] Medical staff who treated domestic patients infected with the novel coronavirus disease (COVID-19) recently expressed a high likelihood that the detected viral genes in the increasing cases of re-positivity are from non-infectious viruses.

On the 29th, the Central Clinical Committee on Emerging Infectious Diseases held a press conference and announced the analysis and research results regarding recent re-positive patients. This committee is a consultative body composed of attending physicians and medical staff responsible for treating COVID-19 patients, as well as related medical institutions such as the National Medical Center. The committee stated, "Even after the virus has been inactivated, fragments of viral RNA (ribonucleic acid, a type of genetic material) can remain inside cells," and added, "The re-detection of the virus is more likely to be the detection of inactivated viral RNA rather than reactivation or reinfection."

According to quarantine authorities, the number of re-positive patients has increased to 292 as of this date. Various possibilities are being considered, including whether these patients were reinfected after recovery, whether the existing virus remained in the body and reactivated, or whether there were errors in the testing methods. The committee explained, "COVID-19 infection and replication occur within respiratory epithelial cells, so even after the virus is no longer active, viral RNA fragments can remain inside epithelial cells," and "After recovery, as epithelial cells naturally shed, viral RNA can still be detected by PCR tests."

Considering these points, it is appropriate to view this as a technical limitation of the highly sensitive PCR diagnostic method. In the case of re-positive patients, it is estimated that the detected RNA is more likely from already inactivated virus rather than reactivation or reinfection.

The committee also explained, "Animal experiments on COVID-19 show that immunity within the body lasts for more than one year after the initial viral infection," and "After infection, antibodies that neutralize the virus are produced in the body, making reinfection with the same virus less likely."

An analysis of 1,868 domestic patients with registered clinical information revealed that 200 patients were hospitalized without symptoms, accounting for about one in ten. The number of severe or higher patients requiring oxygen therapy was 132 (7.1%). Among 1,737 patients who were mild on the second day of hospitalization and the seventh day after symptom onset, most did not experience worsening symptoms over time. The rate of deterioration two weeks after hospitalization was low at 0.7%.

Based on these results, the Central Clinical Committee suggested that mild patients who do not require oxygen therapy initially may be monitored in isolation facilities such as residential treatment centers rather than hospitals if they do not worsen from the third day after hospitalization or the eighth day after symptom onset.

This content was produced with the assistance of AI translation services.