Does the UK’s “REACT-2” antibody study prove that a novel virus was in circulation in 2020?

Written by Jonathan Engler on July 12, 2025. Posted in Current News

published the below critique of the UK’s “REACT-2” study – often cited in support of the notion that a novel virus emerged in 2020 and spread across the world – something that none of us accept happened.

In that article, I pointed out that I had requested some further information from the authors.

On 10 April I emailed as follows:

From: Jonathan Engler
Sent: 10 April 2025 12:49
To: h.****@*********ac.uk; g.*****@*********ac.uk; p.*******@*********ac.uk
Cc: xxxxxxxxxxxxxxx
Subject: Query related to REACT-2 paper

Hello,

I am writing to you in your capacity as corresponding authors named on the below paper, also attached.

REACT-2 Round 5: increasing prevalence of SARS-CoV-2 antibodies demonstrate impact of the second wave and of vaccine roll-out in England.

You state in relation to figure 1 that:

An epidemic curve constructed from date of onset of symptoms in unvaccinated people who were IgG positive shows that the second wave grew more slowly in September to November than the first wave in March-April, and then accelerated in December 2020. (Figure 1).

Please can I ask:

• What tool or tools were used to construct the epidemic curve?
• Is the methodology available anywhere?
• Is there a breakdown of symptoms reported?
• What proportion of those testing positive for IgG had symptoms?
• What proportion of those testing negative for IgG had symptoms?
• Is the raw data relating to symptoms available anywhere – from which I could reproduce said epidemic curve?

Any answers you can provide to the above would be gratefully appreciated.

Many thanks

Dr Jonathan Engler MBChB (UK)

I followed up on 18 June with:

From: Jonathan Engler
Sent: 18 June 2025 14:48
To: h.****@*********ac.uk; g.*****@*********ac.uk; p.*******@*********ac.uk
Subject: FW: Query related to REACT-2 paper

Hello,

I sent the below a couple of months ago but have had no reply.

If you aren’t the correct people please tell me who is.

Thank you

JE

I have heard nothing, which, considering this was a publicly funded study performed by employees of a publicly funded institution, is troubling.

We identified a number of issues with the study, the main one being the absence of publication of the data from those testing negative (for whatever they were actually being tested for); these subjects are effectively the control subjects in respect of any conclusions drawn regarding those who tested positive.

Per protocol, the symptom data was collected from ALL subjects.

The data from the control group remains unpublished. Why?

See more here Substack

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