i’d argue the poor data point. We’ve known about pre-symptomatic contagion since mid-last year and I doubt it changed with a more muscular variant with a much higher viral load generation:
” transmission from asymptomatic individuals was estimated to account for more than half of all transmission.”
https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2774707
The 75% of SARS-CoV-2 transmissions in our cohort from case-patients in their presymptomatic phase exceeds reported transmission rates from other investigations (1,13,14). Possible reasons are the prior evidence that infectiousness peaks around the date of symptom onset, declining thereafter (15), and that case-patients probably reduced social contacts themselves once they experienced symptoms or when ordered to self-isolate. A large proportion of cases with presymptomatic transmission in our cluster is further supported by the median serial interval of 3 days.
https://wwwnc.cdc.gov/eid/article/27/4/20-4576_article
“Up to 50% of people who had COVID-19 in Iceland were asymptomatic after health officials did broad lab testing of the population there.
Nearly 40% of children ages 6 to 13 tested positive for COVID-19, but were asymptomatic, according to just published research from the Duke University BRAVE Kids study. While the children had no symptoms of COVID-19, they had the same viral load of SARS-CoV-2 in their nasal areas, meaning that asymptomatic children had the same capacity to spread the virus compared to others who had symptoms of COVID-19.”
https://www.uchealth.org/today/the-truth-about-asymptomatic-spread-of-covid-19/
(the above UC quote I included because it contained the, high viral load in nostrils, phrase which is the exact same argument being used by unvaccinated who point to only vaccinated as carriers/infectors)
My point was one the WHO made: The higher the quality of contact tracing, the lower the estimate of asymptomatic spread. The WHO noted that studies showed up to have of all spread were asymptomatic, but those were all low quality studies. That discussion was buried in a report I down loaded some time ago and I don’t want to try to dig it out.
This might be relevant:
“The “recent research” the study authors cite is a meta-analysis of 54 household COVID-19 transmission studies that observed 77,758 participants, which was posted as a pre-print this summer and published in December.
The text of the analysis is even more consequential than the CDC’s reference makes it seem: “Estimated mean household secondary attack rate from symptomatic index cases (18.0%; 95% CI, 14.2%-22.1%) was significantly higher than from asymptomatic or presymptomatic index cases (0.7%; 95% CI, 0%-4.9%; P < .001), although there were few studies in the latter group. These findings are consistent with other household studies28,70 reporting asymptomatic index cases as having limited role in household transmission” (emphasis added).
The 0.7 percent figure includes not just people who never show symptoms of COVID-19, but people who haven’t yet shown symptoms—two groups that have been alleged to be major factors driving the spread of the virus. This is a major data point often underplayed or even challenged in much media coverage of the virus.”