Coronamonomania Thrives in Darkness, Part 92

We seem to be sitting on a cusp of whether people, and governments, are going to freak out about cases and vaccines, or whether we are finally just going to stop obsessing about this virus.  I can guarantee you we don’t all want to turn into New Zealand or Australia, which seem determined to become hermit societies where no one ever interacts with anyone else.  The only good thing about the safety-obsessed in the US is they may help even more people become disenchanted with the corrupt, senile, incompetent administration in DC.  Be deeply ironic if it brings down those hacks the same way it did the prior administration.

Through the course of the epidemic, here in Minnesota and elsewhere, various events or activities were used to terrify the population.  One of those was the Sturgis Motorcycle Rally.  Some of our public health experts, including local ones, claimed that thousands and thousands of cases were caused by the rally going on as planned, with very little, gasp, wait for it, mask wearing.  Here is an article attempting to keep the fear alive, but really kind of hilarious.  Tens of thousands of people attended that event.  A whopping 643 cases nationally were blamed on it in the paper, including secondary and tertiary transmission.  The paper refers to this as “widespread transmission”.  That can’t be any more than the background rate at the same time.  (JID Paper)

One notable aspect of the epidemic has been that only those predisposed by age and/or health status tend to get seriously ill and die.  Think of how eagerly and breathlessly the Minnesota DOH staff awaited any opportunity to say a healthy young person died.  It just didn’t happen.  This study from the CDC confirms that CV-19 has little risk for the average person who is in reasonably good health.  (CDC Paper).  Over 540,000 persons who were hospitalized in the year ending in March 2021 were included in the research.  95% had at least one underlying health condition, with hypertension and high cholesterol being the most common, but obesity, diabetes, anxiety disorders and total number of conditions were the strongest risk factors for serious disease.  I will bet that the 5% without an underlying health condition, and quite a few with, were hospitalized for another reason than CV-19 disease or picked up the disease in the hospital.

This study examined viral loads among nursing home residents and staff in Massachusetts with and without symptoms.  It found that initially the viral loads were similar, but that over time those without symptoms had higher cycle numbers, indicating lower viral loads.  (JID Paper).  People without symptoms were obviously far less likely to test positive.  Viral loads had an immense range, with cycle numbers up to 37 being positive.  More people with symptoms than without had cycle numbers under 30.  When overall cases in the state went down, the cycle number gap widened, indicating once again that in a low prevalence environment, PCR tests are picking up a lot of low positives, indicating people who are not infectious.  As the authors note, some selection bias occurs because people with symptoms are more likely tested closer to peak viral load, which appears to be near symptom onset.

Like the US, the United Kingdom has a fairly high adult vaccination rate.  This study looked at the impact of vaccination on household transmission.  (Arxiv Paper).   Timing of vaccination completion and positive cases in a household is important.  Calling some vaccinated before a sufficient time has elapsed for the full adaptive response to be established is misleading.  This paper used 21 days from a first dose, which is likely inadequate, so understates the beneficial effect of vaccination.  The secondary attack or transmission rate in vaccinated households was about half that in unvaccinated ones, 12.5% to 23.5%.  The study did not attempt to identify how the transmission occurred, so could be from or to an unvaccinated person.

Israel is sometimes used as an example of a country with a high vaccination rate that isn’t doing much to slow transmission.  This is false.  Here is the latest paper to demonstrate that.  (Medrxiv Paper).   This study also focussed on household transmission and examined both likelihood of getting infected and being infectious following vaccination.  The vaccine was 80% to 88% effective in reducing likelihood of transmission in a household.  For persons who did become infected, it was 41% to 79% effective in reducing transmission from them.

The simplest way to tell if an intervention or set of interventions is working is by looking at the epidemic curves.  If you look at epidemic curves in the US, and most of the rest of the world, it is pretty clear no intervention or set of interventions, other than vaccination, seems to have made much difference.  This study looked at the supposed effect of stay-at-home orders in rural versus urban areas.  I suspect the authors were interested in shaming those conservative, Trump-voting country hicks.  (Medrxiv Paper).  The study was done on a county by county basis, but since most stay-at-home orders were statewide, curious how this worked.  In any event, such orders were implemented later and for a shorter period in rural compared to urban areas.  Interestingly, compared to baseline, cases increased after a stay-at-home order in both rural and urban counties, but more in rural ones.  Likely just an effect of orders being issued when cases rose, rather than the reverse, but also demonstrates that the orders are pretty worthless.  Interestingly, after the orders expired, there was absolutely no change in the direction of cases between urban and rural counties.  Mobility may be less reduced in rural areas, because people don’t have quite the same access to home delivery for food and other necessities (or to copiers, according to our VP).  I think the study actually supports the idea that the orders make little difference.

India had a big case surge in the prior months, mostly of the Delta variant.  What was the impact on hospitalization, particularly in vaccinated individuals?  According to this paper, even though the vaccinated group was older and had other risk factors, it experienced a much lower rate of hospitalization.  Mortality rates were 50% lower, again not taking into account the higher age.  Those who were vaccinated but got infected and died, were found to have minimal immune response to the vaccine.  The frail elderly, are, well, the frail elderly.  Not a lot can be done to keep them from getting seriously ill.  (Medrxiv Study).  Would have liked some information on relative viral loads.