Covid spreads through the body faster than previously thought, according to a groundbreaking UK study released on Wednesday.
The average duration between being exposed to the virus and its being discovered was 42 hours, according to the results of the world’s first “human challenge” study, in which healthy young adults were purposely infected with Covid.
This is far smaller than the official government guidance estimate of a five to six-day “incubation period.”
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According to a landmark trial in which healthy participants were purposely given a dosage of the virus, exposure to a single nasal droplet is enough to become infected with COVID-19.
The study, which was the first to track patients throughout the course of an infection, discovered that people often acquire symptoms rapidly – on average, within two days of coming into contact with the virus – and are most infectious five days later.
The research was done on a virus strain that existed before the Alpha, Delta, and Omicron versions appeared.
The findings, which were published on Springer Nature’s pre-print service but have yet to be peer-reviewed, describe the outcomes of 36 healthy young people who had no immunity to the virus.
The volunteers were closely followed at the Royal Free Hospital in London’s specialty section and showed no signs of illness.
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The study discovered that the infection begins in the throat and that the infectious virus peaks about five days after infection, at which point the viral load in the nose is considerably higher than in the throat.
The study also concluded that lateral flow tests are a reassuringly accurate indicator of the presence of infectious virus.
According to the findings, swabbing the nose and throat makes it easier to diagnose infections during the first few days.
(With inputs from agencies)
