COVID Transmissions for 10-12-2020
Good morning! It has been 330 days since the first documented human case of COVID-19. Another Monday! Let’s try to have a good week.
Headline focus today.
As usual, bolded terms are linked to the running newsletter glossary.
Keep the newsletter growing by sharing it! I love talking about science and explaining important concepts in human health, but I rely on all of you to grow the audience for this:
Now, let’s talk COVID.
Public health measures really do work!
CDC analysis of the effect of public health interventions continues to confirm that they work. In Arizona, several behavioral measures were instituted to stop accelerated spread of COVID-19 that was taking place in the early summer.
Let’s take a look at how the authors of the CDC study described it:
The average number of daily cases increased approximately 151%, from 808 on June 1, 2020 to 2,026 on June 15, 2020 (after stay-at-home order lifted), necessitating increased preventive measures.
Obviously that’s an alarming increase.
On June 17, local officials began implementing and enforcing mask wearing (via county and city mandates), affecting approximately 85% of the state population. Statewide mitigation measures included limitation of public events; closures of bars, gyms, movie theaters, and water parks; reduced restaurant dine-in capacity; and voluntary resident action to stay at home and wear masks (when and where not mandated).
These are familiar measures for those of us who have lived through the COVID-19 pandemic. These mitigation measures ended up being extended through August to further slow spread. What was the effect?
The number of COVID-19 cases in Arizona peaked during June 29–July 2, stabilized during July 3–July 12, and further declined by approximately 75% during July 13–August 7. Widespread implementation and enforcement of sustained community mitigation measures informed by state and local officials’ continual data monitoring and collaboration can help prevent transmission of SARS-CoV-2 and decrease the numbers of COVID-19 cases.
Now in reality what we are looking at here is correlation and not causation. However, There is nothing particularly unusual about the management of the disease in Arizona, the environmental patterns, or other obvious factors. The public health measures taken do appear to be the most likely cause of what happened here.
You can read the full study in Morbidity and Mortality Weekly Report here: https://www.cdc.gov/mmwr/volumes/69/wr/mm6940e3.htm
How does the typical COVID-19 patient differ from the typical influenza patient?
A huge study from Columbia University has looked at over 34,000 patients to understand how the profile of a typical COVID-19 patient differs from the typical patient from another deadly infectious disease with which we have greater experience.
This study can be found in Nature Communications: https://www.nature.com/articles/s41467-020-18849-z
This was a global study which looked at patients in Spain (n=18,425), South Korea (n=7341), and the US (n=8362).
This was the key conclusion:
Compared to 84,585 individuals hospitalized with influenza in 2014-19, COVID-19 patients have more typically been male, younger, and with fewer comorbidities and lower medication use.
This is interesting, because it portrays a different profile for this disease than what we have become accustomed to. Yes, the information about COVID-19 risk groups is still valid—older individuals, individuals with comorbidities, etc are all still at greater risk from this virus. However! The conclusions here come from—I think—one very important fact: COVID-19 is more deadly and severe than influenza across a broader population.
Keep in mind, also, that we’re just looking at hospitalizations here. We’re not looking at deaths necessarily. This is important, though, for a few reasons. We’ve discussed before that hospitalized patients were likely to face long-term impacts from their disease. Additionally, hospitalizations are a big driver of deaths. People who die often were hospitalized before they did so (though not always by any means), and also the rate of hospitalization affects hospital capacity utilization. The more overburdened hospitals are, the more likely people are to die in hospital care.
Lastly, hospitalization is a big driver of costs, both monetary and in more general resource use. There is a societal benefit in reducing hospitalization.
The results of this analysis may be useful in understanding better which groups of people may be worth focusing on for the purposes of preventing spread. The classical targeting of much older patients with multiple comorbidities—even if these patients may be at greater risk of death—may not be the best population to focus on for the purposes of keeping more people out of hospitals.
What am I doing to cope with the pandemic? This:
A Zoom wedding
This weekend, I attended several Zoom events surrounding the wedding of a dear friend of mine. Though I would have loved to be with them in person, the ability to hear their families come together and share in their celebrations was affirming about what really matters in life and a reminder that these moments of joy can continue through difficult times.
Join the conversation, and what you say will impact what I talk about in the next issue.
Also, let me know any other thoughts you might have about the newsletter. I’d like to make sure you’re getting what you want out of this.
This newsletter will contain mistakes. When you find them, tell me about them so that I can fix them. I would rather this newsletter be correct than protect my ego.
Though I can’t correct the emailed version after it has been sent, I do update the online post of the newsletter every time a mistake is brought to my attention.
No corrections since last issue.
Thanks for reading, everyone! Have a great week!
See you all next time.
Always,
JS