I keep mis-numbering the parts of this series, because it is passing so quickly. No commissioner of health on the briefing call today. I am hoping these end soon, they are a waste of time, nothing but messaging, and ending them would be a great step toward de-emphasizing this non-epidemic. Kris Errorsperson tried valiantly to carry on the terror message in the face of practically non-existent cases, which she referred to as “our case numbers have slowed down a bit”. She also repeated the lie that the percent of cases in younger groups that result in hospitalization has increased. I don’t know why they keep saying this, I have used their data to show that that absolutely is not at all the case. Almost all vaccine talk, and Minnesota is doing well in that regard.
A good summary on the research on the typical period of and features of infectiousness. (Science Article) The research comes from Germany and over 25,000 people were included, across a range of disease severity. The study group was under-represented with older and younger patients. Younger people had lower viral loads and a lower probability of having culturable virus. People infected with the B117 variant had higher viral loads and greater likelihood of culturable virus. The peak of viral loads was between 4 and 5 days after shedding began. Interestingly, people who were asymptomatic or had mild disease had higher viral loads than did hospitalized patients, on average. The most likely explanation might be that hospitalized persons were especially susceptible to any level of infection. Now it gets really interesting, only 35% of positive samples were able to be cultured. That is astounding. And culturability was less likely in hospitalized patients. That suggests people in the hospital picking up small amounts of either virus or fragments when hospitalized, and likely not being hospitalized for CV-19. There was substantial variation in viral load, with most people having relatively small ones and few having very large ones, consistent with other studies showing that a few people are responsible for most infections. And another fascinating finding is that the first positive PCR test appeared to happen well after peak viral load, on average several days after.
And speaking of infectiousness, Sweden has apparently decided to stop using PCR testing because it is incapable of determining if a person is actually infected or infectious. Their research indicates that it is picking up RNA fragments months after infection. Instead they are going to rely on clinical signs and physician judgment. Another example of the greater rationality present in that country. (Swedish Policy)
This CDC report covered breakthrough infections, that is, infections occurring after vaccination. (CDC Report) Over 10,000 such infections had been reported from 46 US states. Over 60% occurred in women, but more women than men may be getting vaccinated. 995 were hospitalized and 160 died. But here is where it gets fun. Among those hospitalized, 30% were asymptomatic or were hospitalized for a reason unrelated to CV-19. Now do that analysis for all CV-19 hospitalizations. And among those who died, 18% were asymptomatic or died for a reason unrelated to CV-19. Now do that analysis for all deaths. When it suits them, the public health gods are perfectly capable of doing analyses that we should have been seeing all along.
This paper is getting a lot of attention, but its central message is similar to that of many other studies: infection creates strong adaptive immunity. (Nature Paper) In this research, the authors focused on a specific type of B cell progenitor, finding that it had good memory for CV-19. The work was done in people with mild infections, and while their circulating antibodies waned after a few months, the memory cells remained in place and responsive to reinfection attempts.
Remember cross-reactive adaptive immune responses from seasonal coronaviruses? This paper would suggest they really are a thing. (Nature Article) The authors found that there was very weak evidence for pre-existing circulating antibodies that cross-react with CV-19, there was good evidence that B memory cells existed which could produce cross-reactive antibodies upon infection.
Kind of interesting work on lags between cases and deaths in multiple US states, including Minnesota. (RS Paper) The CDC suggests the lag is about a median 16 days from case to death. This paper finds it is longer, almost a month. That seems far too long. They were looking specifically at case surges and the lag between a case surge and a deaths surge. They have Minnesota at 41 days. But they used the now-defunct CV Tracking Project data, which relied on state death reporting, which usually, and definitely in the case of Minnesota, is date of report, not date of death. So not very accurate to determine a true causative lag. The CDC data is clinical in origin, and far more reliable for this purpose.
This study from the UK attempted to identify factors associated with post-vaccination infection. (Medrxiv Paper) Frail older adults and those in low-income areas were much more likely to have such an infection, along with obese persons. Symptoms were milder and hospitalizations fewer.
Another paper finding that people who are infected have a strong reaction to the first dose of the mRNA vaccines, while it takes two doses to get a similar response from uninfected persons. (Medrxiv Paper)
Here is some of the trial work on more traditional CV-19 vaccines, using attenuated virus. (JAMA Article) The efficacy was in the mid-70%s, but many people had only received one of two doses. Should rise for fully vaccinated. Make all the people who think mRNA vaccines are gene therapy happy, except they will likely come up with another excuse not to get vaccinated.
And for those who are worried about the adenovirus-vector vaccines, i.e. J & J and AstraZeneca, these researchers hypothesize a reason for the clotting issues they may have been associated with. (RS Paper) Unlike mRNA vaccines, the adenovirus ones are transcribed initially in the nucleus, before being re-exported to the cytoplasm for spike protein production. (Which is why I don’t like those vaccines as much as the mRNA ones.) The authors believe that in the process, splice events may happen which mistranslate spike protein sequences and subsequently trigger production of proteins which cause platelet malfunction.