New Delhi: A new research indicates that those infected by the coronavirus may not be capable of transmitting the virus after 9 days. In a new study that was reported in medRxiv on Tuesday and is awaiting peer review, researchers have said that those infected by the novel coronavirus may not spread the infection after 9 days. According to a report by Reuters, data compiled by UK researchers from 79 studies show that even when the virus is detectable in the throat, nose, and stool the infectious virus particle is not spread nine days after symptoms begin. The different studies that were used in the research included ’79 studies on SARS-CoV-2, 8 on SARS-CoV-1, and 11 on MERS-CoV’.
The report says that the genetic material of the virus, the RNA, is present in throat swabs for an average of 17 days to 83 days from the onset of symptoms. But the RNA itself is not infectious. The lead researchers Muge Cevik and Antonia Ho also said PCR tests detect these ‘non-viable genetic material’ because of its sensitivity. They also added that attempts to culture the virus beyond nine days have been unsuccessful.
‘Although SARS-CoV-2 RNA shedding in respiratory and stool can be prolonged, the duration of viable virus is relatively short-lived. Thus, detection of viral RNA cannot be used to infer infectiousness.’ says the abstract of the paper.
Both Cevik and Ho said in the report, “Many studies agree patients with SARS-CoV-2 infection have a very high viral load…in the first week of illness (and) seem to be most infectious from symptom onset to day 5. This suggests many people by the time they are tested are already beyond their most infectious period,” both the researchers said in the report.”
According to the researchers, the study points to the importance of early isolation of suspected Covid 19 cases. They also said that those who are asymptomatic are also likely to contagious soon after becoming infected.
‘This review underscores the importance of early case finding and isolation, as well as public education on the spectrum of illness. However, given potential delays in the isolation of patients, effective containment of SARS-CoV-2 may be challenging even with an early detection and isolation strategy’ reads the abstract.