THE CONFUSION between a R0 at 18 for MEASLES and an R0 at 2,5 for WUHAN or at 5, 10, even 20 (in a recent study) for OMICRONS
2) The basic reproduction number R0 is when one person develops an infection and passes it to 1, 2, 10 or 18 persons. It is relevant in a population with no immunity as for example, people not vaccinated against measles.
3) When widespread immunity starts to develop, we will use the Re effective reproduction number or Rt.
Re is the number of people in a population who can be infected by an individual at any specific time. It changes as the population becomes more or less immunized.
3) If the R0 of Wuhan strain was estimated a 2.5, with the increasing immune escape of Omicrons, it is increased to nearly 8.
4) In a recent study, they even estimated the R0 of Omicron at 20.
5) But, once again, due to the level of immunity of a part of the population, what is interesting for COVID-19, is the Re which depends in a country on the average level of immunity of the population.
Thanks for reading 🙏
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AUTOANTIBODIES, when the IMMUNE SYSTEM SABOTAGES ITSELF !
Autoantibodies are antibodies that mistakenly target the body's own tissues instead of fighting against pathogens like SARS-CoV-2. They contribute to the dysregulation of the immunity and can lead to autoimmune reactions
3) This is a key subject between the role of antibodies and that of SARS-COV-2 infection, a subject which is regularly addressed at the Dresden symposium : sciencedirect.com/science/articl…
2) SUMMARY
Leukocytoclasia in the brain, in COVID-19 autopsy cases, indicates a localized inflammatory response involving the destruction of white blood cells within the brain tissue.
Fig. Cerebral microvasculopathy with mural collagenosis.
3) All 36 cases had acute neutrophilic vasculitis with a variable amount and distribution within the cohort from frontal lobe to medulla
▶️ Natural infection of SARS-CoV-2 in dogs associated with fatal disease is first reported.
▶️ Viral loads and distribution of SARS-CoV-2 in various organs were determined using RT-dPCR and IHC sciencedirect.com/science/articl…
2) 2nd study
"Neurologic Effects of SARS-CoV-2 Transmitted among Dogs"
Diagram representing susceptibility to infection in the lungs and brain of animals with potential for human transmission and homology of ACE2 in study of the neurologic effects wwwnc.cdc.gov/eid/article/29…
3) Fig. SARS-CoV-2 in the brain of dogs in study of the neurologic effects of SARS-CoV-2, showing transmission at an early stage of infection
2) Abstract :
The first-generation Spike-alone-based COVID-19 vaccines have successfully contributed to reducing the risk of hospitalization, serious illness, and death caused by SARS-CoV-2 infections. However, waning immunity induced by these vaccines failed to prevent immune .
3) ... escape by many variants of concern (VOCs) that emerged from 2020 to 2024, resulting in a prolonged COVID-19 pandemic. We hypothesize that a next-generation Coronavirus (CoV) vaccine incorporating highly conserved non-Spike SARS-CoV-2 antigens would confer stronger
Why the HOST IMMUNE SYSTEM in COVID-19 resembles that of INDIVIDUALS with AUTOIMMUNE CONDITIONS ?
H/t @inkblue01 @Dakota_150
As this is a complex subject and a complex study presented, we will develop it in several stages.
2) Certain fragments of the SARS-CoV-2 virus can mimic peptides that are naturally produced by the immune system. These viral fragments, known as "molecular mimics," can bind to receptors on immune cells and trigger an immune response.
3) However, because these viral fragments are not identical to the immune system peptides, they can lead to a dysregulated immune response, causing excessive inflammation.
Orthologs are genes that are derived from a common ancestor and perform similar functions in different species
2) Interesting study
"We applied this assay to test a panel of 30 ACE2 orthologs or human sequence mutants for infectability by the original SARS-CoV-2 spike protein or the Alpha, Beta, Gamma, Delta, and Omicron BA1 variant spikes." biorxiv.org/content/10.110…
3) Out of the thirteen non-human orthologs, ten exhibited unique patterns of variant-specific compatibility, demonstrating that spike sequence changes during human transmission can toggle ACE2 compatibility and potential susceptibility of other animal species ...