Starting the week with some interesting research summaries. First up is a study from France which attempted to ascertain changes in people’s mobility patterns following mitigation of spread measures. (Medrxiv Paper) 42,000 adults were tracked during the lockdown in April. Overall daily contacts dropped by 70%, with a substantially greater rate of decline among those over 65 than for younger adults. Use of public transport dropped from 37% to 2%. Of those who went to work before the lockdown, 68% began working at home, and 17% were unemployed. Not only was the number of contacts reduced but the type of contact and where it occurred was as well. There was a massive reduction in use of health care services, even among those with chronic diseases. It is interesting as well to note that there were very few contacts between the old and people under 20 and other adult age groups. The data does not support the notion that young people have frequent contacts with the elderly and might be transmitting to them.
This is a study that was actually published in February before the epidemic was in full swing in the US, but after CV-19 had been identified as a public health threat. It looked at various parameters related to respiratory viruses and the illnesses that they cause. (Medrxiv Paper) The authors were examining influence-like illness, which is the broad category for respiratory viruses, the most common of which from a clinical perspective is influenza. They stressed the importance of now beginning to test more frequently and carefully for exactly which pathogen is responsible for an influenza-like illness. They provided best-estimate parameters for five common respiratory viruses from a literature search. These included influenza, coronavirus, rhinovirus, adenovirus and respiratory syncytial virus. Interesting to note that the seasonal coronaviruses can cause a fair amount of mortality, especially the strain most similar to CV-19.
Italian schools reopened with few cases of CV-19 according to this study. (Medrxiv Paper) 1212 out of 65,104 schools reported a CV-19 case, for a total of 1350 cases, 1059 of which involved students. You can see that it was rare for a school to have more than one case, which the authors said showed limited spread among children. You wonder how many of the cases were false positives, or whether that was even checked. Schools were closed on the basis of one or a few cases, just like here. More evidence that infection rates among children are low and they play a limited role in transmission.
Another paper on CV-19 antibody development. (Medrxiv Paper) The group identified development of antibodies to a wide spectrum of the CV-19 proteins, including spike protein, receptor-binding domain, membrane protein and other regions. They used 40 recovered CV-19 patients and 20 unexposed persons to do the antibody profiling. The CV-19 antibodies showed frequent cross-reactivity to segments from the seasonal coronaviruses. 50% of the unexposed controls also showed cross-reactivity of seasonal coronavirus antibodies to fragments from CV-19.
I generally avoid the many masking model papers. Here is one from the IHME, the group that did horrific modeling on the US epidemic in the spring, creating absurd over-estimations of deaths. They did the same thing recently, with revised projections that are already far above reality. It is a Gates funded group that is ideologically driven. This latest effort purports to show that universal masking would save over 800,000 lives by January 1. They claim that mask use cuts transmission by 40%. Not according to macro-correlations of mask use and cases. According to those analyses, there is absolutely no relationship between mask use and cases. The evidence cited in support of masks cutting transmission is the usual other modeling studies, coupled with the physical studies of particle/mask interaction. Obviously no real trial evidence on mask benefit in cutting community transmission of CV-19, since it doesn’t exist. (Medrxiv Paper) I am not going to bother going into a lot of detail, but one interesting aspect is how they completely avoid discussing Scandinavia, where mask use is extremely low, and so are cases and deaths. But they do project lots of deaths there.