Covid-19 is a “short-lived” infection that lasts for only nine days after patients begin to show symptoms, according to a new study that shows patients to be “highly infectious” very early on in the illness, peaking within five days of showing symptoms—a time period so short that researchers believe it can explain why the pandemic has been so hard to contain and how it has managed spread so quickly.
Research suggests Covid-19 patients are most infectious within the first five days of showing … [+] symptoms.
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The research, published in Lancet Microbe, indicates that patients have high levels of “live” virus — which is capable of replicating and potentially infecting others — within the first five days of showing symptoms, with none detected after nine days.
These high levels of live virus suggest Covid-19 patients are “highly infectious” early on, highlighting the need for rapid contact tracing and isolation.
Though no live virus was detected after nine days, fragments of viral genetic material could, in some cases, be detected for weeks afterwards, leaving some tests used to determine infectiousness inaccurate.
Dr. Muge Cevik, the study’s lead author, said that the findings suggest repeat PCR testing — the accurate laboratory test used to detect viral genetic material — may not be appropriate to determine whether someone is no longer infectious and able to stop self-isolating, as results “could remain positive for much longer and [do] not necessarily indicate