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Disinformation about COVID-19 courtesy of Zweig and Brand

Russel Brand has his hobby horse of freedom over public health, because pharmaceutical companies are making money then everything and everyone is suspicious and corrupt. A recent video “This Changes EVERYTHING We Were Told” 2023-05-20 goes on a bender about based on an article by David Zweig, a reported from SubStack.

Zweig appears to be talking about a conference presentation that refers to an original paper (Hogan) that just highlights a slow and complex test that can tell if a person has an infectious version of the virus or an inactive version, as opposed to PCR which just detects for the presence of the parts of the virus – regardless if infectious or not.

Zweig seems to be confusing this with other papers that have determined that asymptomatic persons are less infectious, and is placing a large amount of weight on a conference paper that has a small sample (n=1074). While Zweig claims 96% of asymptomatic persons were not transmitting, a meta-analysis by Ravindra found 24.51% of asymptomatic cases were infectious.

Noting that asymptomatic infection is NOT the incubation period, which is the approximate time from the first exposure to the virus until the clinical symptoms or signs onset, during which the person is most definitely infectious.

In a systematic review, Zhiru states “many patients with COVID-19 are asymptomatic or have only mild symptoms, but they are able to transmit the virus to others”.

What proportion of infected persons were asymptomatic? Zhiru has a wide range over a few small studies, but Qiuyue used a meta analysis giving a much larger population, found about 40% of those with PCR confirmed COVID-19 were asymptomatic.

So if you are not demonstrating symptoms you don’t know if you are infected, you may be in the early stage or you may be asymptomatic. If you are asymptomatic then you may not be infectious – but definitely still can be.

The original Hogan paper was about determining if a patient was infectious with an active version of the virus or non-infectious with an inactive version of the virus. This was nothing to do with asymptomatic infections. The paper included caveats that the test was slow and complex.

Zhiru Gao, Yinghui Xu, Chao Sun, et al. 2021. A systematic review of asymptomatic infections with COVID-19. J Microbiol Immunol Infect. 2021 Feb; 54(1): 12–16. doi:10.1016/j.jmii.2020.05.001

Qiuyue Ma, Jue Liu, Qiao Liu, et al. 2021. Global Percentage of Asymptomatic SARS-CoV-2 Infections Among the Tested Population and Individuals With Confirmed COVID-19 DiagnosisA Systematic Review and Meta-analysis. JAMA Netw Open. 2021;4(12):e2137257. doi:10.1001/jamanetworkopen.2021.37257

K. Ravindra, V.S. Malik, B.K. Padhi, et al. 2022. Asymptomatic infection and transmission of COVID-19 among clusters: systematic review and meta-analysis.
Public Health, V203,pp100-109.

Catherine Hogan, ChunHong Huang, Malaya Sahoo, et al. 2021. Strand-Specific Reverse Transcription PCR for Detection of Replicating SARS-CoV-2. CDC: Emerging Infectious Disease. 2021;27(2). doi:10.3201/eid2702.204168

Ralph Tayyar, Melanie A. Kiener, Jane W. Liang, et al. 2023. Low Infectivity among Asymptomatic Patients with a Positive SARS-CoV-2 Admission Test at a Tertiary Care Center, 2020–2022. CONFERENCE PRESENTATION.

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