Nature Medincine: The first human active infection challenge test with the new coronavirus, revealing the attack and transmission mode of the new coronavirus

Recently, a new round of new crown epidemics appeared in Shanghai and Jilin and other places.

Researchers from Imperial College London published a research paper titled: Safety, tolerability and viral kinetics during SARS-CoV-2 human challenge in youngadults in thetop international medical journal Nature Medincine

The study recruited 36 young, healthy volunteers to participate in the first-ever COVID-19 challenge study in humans

For many years, controlled human infection models (CHIMs) have been used to study disease pathogenesis and to evaluate preventive and therapeutic approaches

In fact, as early as March 2020, researchers from Rutgers University, Harvard T.

Once the article was published, it caused widespread controversy

In young people, infection with Covid-19 is often mild or asymptomatic, but this may drive community transmission, although the detailed time course and contagiousness of early infection are not fully understood

In this latest study, the research team recruited 36 healthy adults aged 18-29 to participate in the challenge trial.

Research flow chart

Of the 34 seronegative volunteers, 18 (53%) were infected, the viral load peaked 5 days after vaccination, and all infected individuals developed SARS-CoV-2-specific IgG and neutralizing antibodies

What's more, the study found that the volunteers spread the virus for an average of 6.

Virus transmission peaks rapidly after a short incubation period after infection

Of the 18 infected, 2 (11%) were asymptomatic, and most of the others had mild symptoms.

Human COVID-19 challenge can induce mild to moderate symptoms

Now, the research team plans to conduct another challenging study in a vaccinated population infected with the Delta mutant strain

Dr Christopher Chiu , the study's corresponding author , said: "In fact, no other type of study has done this, because often patients only pay attention when they develop symptoms, so early signs of infection are often missed.

In conclusion, this study establishes the viral dynamics during the initial and early infection of 2019-nCoV through the detailed description and safety analysis of the first-ever 2019-nCoV infection challenge study in young healthy adults, and public health recommendations and strategies for 2019-nCoV transmission.
Control strategy has far-reaching effects
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It is worth noting that these "human challenge studies" are controversial because they carry certain risks - does direct infection with the new coronavirus pose unpredictable dangers to volunteers? In addition, it remains to be verified whether such a small-scale trial with a highly controlled and uniform nature can be generalized to the population
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