Drowning in Coronavirus Research, Part 64

After a long road trip home yesterday, trying to catch up on some research and articles.

Here is a new website that compiles a lot of more realistic information and data about the epidemic.  Just need to be a little careful that the spin isn’t too far away from the reality that this is a serious public health concern.   (Rational Ground site)

Let’s start with some more basic data on the coronavirus family.  (Medrxiv Paper)   The researchers were comparing genomic sequences among the various strains.  Coronavirus, like most viruses, tend to mutate, recombine, and have cross-host transmission changes.  The authors looked for clusters of commonality across both human and other host-organism strains, and then created a kind of evolutionary and family tree.  They found evidence for frequent host-jumping events.  After reading the paper, you are left with the impression that we should expect regular evolution of new strains which may jump to humans and cause serious illness.

The CDC released a new survey showing a heightened rate of anxiety and depression among adults due to the epidemic and lockdowns, with 40% reporting some mental health symptom and most alarmingly, 13% reporting new or increased drug or alcohol use, with the highest rates of each among young adults.  (CDC Report)   Almost 11% reported having seriously considered suicide, with young people aged 18-24 reporting the highest prevalence, 25.5%.  That is a quarter of our young adults saying they have thought about suicide.  This group has an incredibly low actual risk from the disease, and they know that, so this is due to the isolation, loss of jobs, loss of college and other factors from lockdowns.

I ran across some remarks by Governor Cuomo in March in which he almost displays some common sense, speculating that the widespread lockdowns and stay-at-home orders may actually have made the epidemic worse.  (NY Post Story)   Maybe making people stay at home actually encouraged spread.  Ya think?  And gee, maybe it would be better to just isolate the vulnerable.  Nahh, way too logical.  Let’s just keep everyone locked up, and hey, maybe we send some of those coronavirus patients to nursing homes for recovery.  What could possibly go wrong with that.  Like most politicians, common sense isn’t the intuition that Cuomo follows.

Another contact tracing study from China.  (Annals Article)   3410 contacts of 391 index cases were traced.  127 of the contacts were positive, most were symptomatic.  The rate of secondary transmission was highest in households, with 83% of all secondary transmissions occurring in that setting.  (Once again, how much sense does forcing people to stay at home make.)   The rate of secondary transmission increased with the severity of disease in the index case, with asymptomatic index cases having the lowest rate of transmission.  While children under age 18 were a small percent of index cases, they were apparently responsible for some transmission to secondary cases, but not identified in the report was whether those were other children or adults.  Encouragingly, the overall secondary attack rate was less than 4% among even close contacts.

Houston got a lot of attention in the recent Texas case surge for supposedly facing a serious risk of overwhelmed hospitals, which didn’t happen.  A study looked at characteristics of hospitalized patients in the initial round of cases in Houston, from March 13 through May 15,  versus those in the latest round, May 16 to July 7.  (JAMA Article)   In the later set of cases, patients were somewhat younger, more likely to be Hispanic, and somewhat lower income.  They also had significantly better health, with lower rates of comorbidities.   Only about half as many were admitted to ICU and length of stay was a third lower and the death rate was half that of the set of hospitalized patients.

How about another paper on transmission mechanics, this one on droplets in confined spaces.  (Medrxiv Paper)   The authors used a model to simulate airflow and droplet concentration in an enclosed space, like a restaurant, with just standard air conditioning.  They showed that droplets and virus could build up over time to infectious levels.  Hmmm, can you think of another enclosed space, like maybe the typical household.  The authors recommend increasing airflow to help disperse droplets and aerosols faster.

And how about an antibody prevalence study with a twist, examining rates in children who had household exposure to adults with infections.   (Medrxiv Paper)  It comes from Italy and examined 80 household contacts of 30 index cases.  Both child and adult contacts had rates of antibody prevalence over 50%, with adults having a slight higher rate.  Please note that all the index cases were adults.  Please also note that this is all household transmission.