Rapid antigen tests are widely used now for home testing and in other settings. Their accuracy is a matter of some controversy. They appear to miss some “cases” but to actually be better than PCR at detecting people who are infectious. This research from Germany finds that their sensitivity, or ability to detect true positives, appeared to lessen during the epidemic’s later phases. This is puzzling because at the same time median viral loads in symptomatic persons were increasing dramatically. The authors attribute the discrepancy to vaccination and prior infection rates, but I don’t see how that would affect test results, unless viral loads were actually lower. It could be that notwithstanding the median viral load, there could be a number of people with low loads who are missed as “positives”, but that may be a sign of greater accuracy in detecting truly infectious persons. (SSRN Study)
Contrary to some other studies, this research from Indonesia finds that Omicron and Delta patients had similar viral loads and rates of hospitalization and death. It is highly likely, however, that a number of Omicron cases were missed, making rates appear higher than they actually are. And vaccination status was not considered. (Medrxiv Paper)
This study from highly vaxed England is more typical in finding that both ER visits and hospitalizations were substantially lower for patients infected with Omicron, compared to Delta. (Medrxiv Paper)
Study after study is now confirming the obvious; lockdowns and the terror campaign during the epidemic caused a significant increase in mental health issues and suicidal thoughts, particularly among younger people. This study comes from the Netherlands. (Medrxiv Paper)
Australia had a vicious lockdown policy during most of the epidemic. As we have seen elsewhere, this resulted in missed health care and presentation with more serious disease. This study looked at stroke and found a significant decrease in ER visits from stroke symptoms and a concommitant presentation with more serious symptoms which led to worse outcomes. Congratualtions for the experts on being so concerned about overall public health and not just focusing on CV-19. That is sarcasm. (Medrxiv Paper)
This is a purported meta-review of studies assessing the prevalence of asymptomatic infections by age, but only included studies through October of 2020. But the proportion of asymptomatic infections overall was quite high, 44%, with a strong age gradient. Almost all infections among the young were asymptomatic and there were few among the oldest age group. (Medrxiv Paper)
A high percentage of children with supposed CV-19 symptoms test negative. This research examined what symptoms appeared most likely to distinguish those who actually had CV-19 versus those who did not. As with adults, loss of taste or smell was a strong distinguisher as was myalgia, or muscle pain. (Medrxiv Paper)
Contrary to the suggestions of some studies, this one finds that a third dose of vaccine, while lessening in protection over time as measured by antibody concentration and neutralization capability and T cell levels, did so at a slower rate than following a second dose. It is pretty apparent to me in the current wave in the US that vaccine effectiveness against infection is essentially zero, regardless of number of doses. (Medrxiv Paper)