The Heat is On
Mark Crislip
My wife and I enjoy seeing cover bands. One of our favorites is Cashed Out, a Johnny Cash tribute. Still not going to any shows this year while delta rips through the world. But I saw Megadeath is coming to Portland next month. Who knew there was a COVID cover band?
People, including me, are prone to seeing patterns where none exist. One of the many cognitive errors that bedevil cognition.
This month I have had three cases of Cryptococcus. Unusual in that I rarely see that many in a year.'
Clustering illusion, right?
The clustering illusion is the tendency to erroneously consider the inevitable "streaks" or "clusters" arising in small samples from random distributions to be non-random. The illusion is caused by a human tendency to underpredict the amount of variability likely to appear in a small sample of random or pseudorandom data.
But the last several months have been hot. Hottest ever. Are the two connected? Or true-true and unrelated.
Maybe related. The range of many infections and their vectors has changed since I started practice back in the cooler 1990s. Why not Cryptococcus?
The present study showed that recent climate changes have significantly affected the distribution of the fungal pathogen C. gattii VGI in Europe and the Mediterranean area. The analysis revealed a gradual expansion of the fundamental niche of the fungus from 1980 to 2009 and an impressive increase in the last decade (2010–2019), during which the environmental surface suitable for the fungal survival was more than doubled.
and
Cryptococcus deuterogattii, previously named Cryptococcus gattii VGII, was recently elevated to a species within the Cryptococcus gattii species complex. C. gattii complex species were traditionally associated with tropical and subtropical climates; however, in recent years, C. deuterogattii has emerged in the temperate regions of western Canada and the Pacific Northwest of North America, where it caused hundreds of infections in people and animals. Interestingly, C. deuterogattii has a higher level of thermal tolerance than other C. gattii complex members, indicating that it may have a greater capacity for thermal adaptation
and
C. gattii results for tree and air samples were more likely to be positive during periods of higher solar radiation.
Higer solar radiation describes July and August. So maybe.
There is at least some good news. I was asked yet again when COVID was going away, and I said never. But maybe not.
We found that 60.0% of the confirmed cases of coronavirus disease 2019 (COVID-19) occurred in places where the air temperature ranged from 5 °C to 15 °C, with a peak in cases at 11.54 °C.
That is a peak of 53 degrees for you metric impaired.
Our results indicate that approximately 85% of the COVID-19 reported cases until 1 May 2020, making approximately 3 million reported cases (out of approximately 29 million tests performed) have occurred in regions with temperature between 3 and 17 °C and absolute humidity between 1 and 9 g/m3. Similarly, hot and humid regions outside these ranges have only reported around 15% or approximately 0.5 million cases (out of approximately 7 million tests performed). This suggests that weather might be playing a role in COVID-19 spread across the world.
So the good news? When temperatures hit 120 F, COVID is unlikely to be transmitted, and that will end the pandemic.
Yeah.
Rationalization
Global warming impact on the expansion of fundamental niche of Cryptococcus gattii VGI in Europe https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8251527/
Climate change and the emergence of fungal pathogens https://journals.plos.org/plospathogens/article?id=10.1371/journal.ppat.1009503Climatic
Influences on Cryptococcus gattii Populations, Vancouver Island, Canada, 2002–2004 https://wwwnc.cdc.gov/eid/article/21/11/14-1161_article
Effects of Weather on Coronavirus Pandemic https://pubmed.ncbi.nlm.nih.gov/32727067/