Tillett

> I have to say, I cannot understand why the idea of doing a challenge trial is controversial. If you are using healthy, young, volunteers who are observed and have good access to medical care, how could it be unethical?

I think the most prelevant is COVID-19, at full strength, still kills seemingly healthy young people. The author mentions this in another article:

> The important question we have to consider is if it is ethical to deliberately expose even the young and healthy to the dangerous SARS-CoV-2 virus when we know it could seriously injure or kill them.[0]

In this article, we potentially have a weaker strains on our hands that could qualify as a fully ethical challenge trial that could accelerate the development.

At the end of the day, challenge trials are Phase trials with less restrictions in hopes of trading accuracy/rigor for speed.

Is it worth it? I don't know. I'm not knowledgeable enough to say one way or another.

[0] https://www.tillett.info/2020/04/24/it-is-unethical-to-not-search-for-an-attenuated-sars-cov-2-strain/

This is a follow up post to a previous post on mine on how we might look for a natural attenuated (mild) strain of SARS-CoV-2 by genome sequencing [0]. While the COG-UK has not been looking directly for such a strain, their data does show that strains with the right type of mutations do exists.

While it might be possible to use a natural attenuated strain as a vaccine directly, the real value of having such a strain may be in using it as a safer test strain in a human challenge trial of a conventional vaccine. This could shave many months off us getting an effective vaccine for COVID-19 [1].

0. https://www.tillett.info/2020/04/05/a-solution-to-covid-19/

1. https://www.tillett.info/2020/04/24/it-is-unethical-to-not-search-for-an-attenuated-sars-cov-2-strain/

I wrote down the reason why the virus is “getting” weaker. There is no explanation of the phenomena in the article, the doctor just talks about what he experiences without an explanation. Social distancing alone wouldn’t help us, we also need the herd immunity, otherwise the virus would just flare up randomly the second we ease the restrictions. The mechanism I mentioned helps us to achieve herd immunity with time. I don’t understand why is that getting downvoted...
Meanwhile I found the article:
https://www.tillett.info/2020/04/05/a-solution-to-covid-19/