Coronamonomania Lives Forever, Part 168

Children and infants were greatly harmed by the response to the epidemic.  This study was done in Ireland and found that during the epidemic infants were slower to begin to speak and develop other normal behaviors.  Congratulations to Timmy Walz and the other morons who did this.  (BMJ Article)

The effect of vaccines on all-cause mortality is to me a weird thing to study, because it is so confounded by the impact of the epidemic response on health and health care behaviors.  But this study from Sweden looked at the effect of a second booster on all-cause mortality in long-term care residents.  The fourth dose appeared to be associated with a reduction in the risk of all-cause death compared to three doses, but the protection waned after a couple of months.  (PubMed Article)

An interesting review of influenza from the years 2010 to before the epidemic, including an assessment of vaccines.  As we have seen with CV-19, regardless of the severity of influenza in a particular year, vaccine effectiveness tends to be low.  Respiratory viruses are hard to stop, so vaccine effectiveness should be measured solely by ability to limit serious disease.  I just don’t think it is feasible to imagine widespread prevention of infection.  (JID Article)

Qatar continues to put out good research on epidemic topics.  In this paper the impact of a prior infection with a non-Omicron variant was compared to that of a prior infection with an Omicron variant.  There were reinfections in both groups but none resulted in severe, critical or fatal illnesses.  People who had a prior Omicron variant infection were somewhat more protected against reinfection with a later Omicron variant, than were those persons with a non-Omicron prior infection.  But people who had both a non-Omicron and an Omicron infection had the broadest protection against subsequent infection.  (NEJM Article)

How did the proportion of infections which resulted in hospitalization or death change over the course of the epidemic. To answer that you would have to assume either that all infections were detected or that the ratio of detected to undetected infections remained the same during the epidemic and that you weeded out incidental hospitalizations and wrongly attributed deaths, and that the ratio of those events to total events stayed unchanged during the epidemic.  In other words, studies lookin at those proportions are likely to be pretty inaccurate.  Nonetheless, worth thinking about, since Omicron is milder and a lot of infections are now reinfections or breakthroughs.  According to this research from England, the death rate and hospitalization rate rose during Alpha and Delta and declined during Omicron.  Average time from positive test collection to hospitalization was 19 days and to death was 26 days earlier in the epidemic, but supposedly declined to 7 days and 18 days during Omicron.  (Medrxiv Study)

I thought all along that the ultimate infection fatality rate from CV-19 would likely be similar to flu.  There was nothing in the symptoms to think otherwise.  This study looking at the IFR for people under 70 and using seroprevalence estimates, finds that in fact that IFR is a lot lower than most published numbers and gee, looks a lot like the flu number.  (Medrxiv Paper)

This is a pathetic study attempting to compare vaccination rates in children in different states with rates of ER visits and hospitalizations, only it completely ignores the biggest confounder, whether the children had also been infected.  Even then, during Omicron there was basically no association between vax rates and outcomes.  Oh, but look, the study was funded by the CDC.  That explains everything.  (Medrxiv Paper)

This was a household transmission study from Nicaragua.  Transmission after an index case occurred in 72% of households and 42% of household members became infected.  Symptomatic persons were more likely to transmit.  Children were less likely to transmit than were adults.  Adults that were the index case in a household and who had a prior infection had an equal likelihood of transmitting to others in the household as those index case adults without a prior infection, but non-index cases adults were half as likely to become infected as adults without one, but this effect was not seen in children.   (Medrxiv Paper)

A study from Serbia looks at reinfections in children.  While reinfections were not common, they increased every month following the initial infection.  Initial infections in children were rarely severe, and they became even less frequent with reinfections, with no deaths and almost no hospitalizations.  (Medrxiv Paper)

Most people have both been infected and vaxed.  If you had a non-Omicron infection and were not vaxed, according to this study from Canada you had a 44% reduction in risk of an Omicron infection and 81% reduction in hospitalization risk.  There was a modest improvement in those numbers if you were also vaxed.  A booster really didn’t add much beyond two doses.  (JAMA Study)