Summary
- If COVID cases necessarily spike in cold weather, it would be reasonable to expect more lockdowns in countries, like the US, which are about to transition from warm to cold weather.
- These lockdowns would presumably have a negative economic effect, and likely a severe negative effect on equity prices.
- This post looks at data from Brazil and the US, and concludes that COVID infections may not be significantly influenced by the weather.
- The reason may be a compensatory adaption feedback loop – people adapt in a compensatory way.
- In fact, if compensatory adaptation theory is any guide, it would not be surprising to see COVID infections actually go down, as a country with growing COVID infections transitions from warm to cold weather.
Do COVID cases spike in cold weather?
If COVID cases necessarily spike in cold weather, it would be reasonable to expect more lockdowns in countries, like the US, which are about to transition from warm to cold weather. These lockdowns would have a negative economic effect, and likely a severe negative effect on equity prices. But is it inevitable that COVID cases spike in cold weather?
To answer this question, it may be instructive to look at COVID figures for Brazil and the US, because these two countries have had similar responses to the pandemic (); and have opposite weather patterns – when it is hot in the US, it is cold in Brazil, and vice-versa. This applies particularly to the most populous areas of the two countries.
COVID figures for Brazil and the US
At the time of this writing, we had the following approximate numbers for Brazil and the US. Brazil – population: 209.5 million, COVID cases: 4.12 million, and COVID deaths: 126 thousand. US – population: 328.2 million, COVID cases: 6.26 million, and COVID deaths: 188 thousand. The two graphs below show the two following ratios: cases-to-population, and deaths-to-population.
The ratios are too close to support the “spike hypothesis”
In the last several months since the pandemic hit both countries, it has been generally cold in Brazil and hot in the US. Given this, these ratios are too close to support the assumption that COVID cases spike in cold weather. So, what would be a reasonable answer to the question posed earlier: do COVID cases spike in cold weather? The answer is: probably not.
What is happening? Compensatory adaptation
This brings to mind another question: would indoor activities, such as restaurant dining and movie theater attendance, lead to spikes in COVID cases?
Well, the idea was that cold weather would lead to more indoor activities ...
While risk of infection may go up with cold weather and more indoor activities, people react in a compensatory way – e.g., by wearing masks, resorting to social distancing etc. This is compensatory adaption theory at work (,). This feedback loop may lead to unexpected results.
If we use compensatory adaptation theory as a guide here, it would not be surprising if COVID infections were to go down, as a country with growing COVID infections transitions from warm to cold weather.
