Why I think a second wave next winter is inevitable.

[NameRedacted]

I apologize if this has been discussed already but so much has been posted I don't have time to read it all.



I think the biggest determining factor by far in the spread of this disease is the outside temperature.


The other factors are:


How densely populated a region is.
How isolated it is from travel from infected areas.
What preventative measures have been imposed such as social distancing
How poor the population is.
Quality of heath care.


But the temperature is the one we have the least control over.


When this disease first started spreading in New York, I was thinking "Jesus, how bad is this going to get in places like India or Egypt or Nigeria?" But that never happened. If you look at this web-site:


https://www.worldometers.info/coronavirus/


and compare countries by deaths or infections per million population, the hot countries are all significantly lower.


Why is Australia doing so well despite almost everyone living in cities?
Why is Mexico doing so well compared to the US?
Why is Africa barely affected?
Look at India - deaths per million - 0.6.

In our own country, why are Florida, Texas, California and Hawaii all doing so well compared to New England?
Why are the meat packing plants in Iowa and Dakota affected so badly but not the plants down in the southern states.


The only reasonable explanation is that the outside temperature is a big controlling factor. And looking at the numbers it's not just a big factor it's the dominant factor.



So what I think will happen is that as the weather warms up, the numbers will fall dramatically. Everyone will declare victory and open up the economy. Then when the temperature starts to fall in late November and through December and January it will come back with a vengeance and this time will affect almost every state much worse because it will be attacking at a time when the temperature is much lower than it is now.



I don't see any simple solution to this. The main advantage that we have is that we know what to expect so will be better equipped to fight it during the critical early stages.

 

[Dtail]

Perhaps it is true to some extent, but appears to be more so with the death rates vs. Cali and FLA still have over 30k cases each.
So maybe the severity in the % of cases is less.

 

[fisemper]

Why is Australia doing so well despite almost everyone living in cities?
Why is Mexico doing so well compared to the US?
Why is Africa barely affected?
Look at India - deaths per million - 0.6.

In our own country, why are Florida, Texas, California and Hawaii all doing so well compared to New England?
Why are the meat packing plants in Iowa and Dakota affected so badly but not the plants down in the southern states.

I am only speculating, but some of the countries are poor and don't have the ability to test their sick so some may be under-reporting to no fault of their own. I also wonder why Mexico and Canada are not doing as bad as the US. I think some are just not truthful and not reporting correctly.

 

[Rustic23]

Florida, California, and Texas are three large states (size and populstiion). That could skew the data.

 

[atmsmshr]

I am only speculating, but some of the countries are poor and don't have the ability to test their sick so some may be under-reporting to no fault of their own. I also wonder why Mexico and Canada are not doing as bad as the US. I think some are just not truthful and not reporting correctly.

Agreed

 

[Spock]

I think the only temperature impact is cold weather keeps people indoors/confined spaces more. To kill viruses you gotta get temps north of something like 165F.
Supposedly hot+humid weather slows this bug down. But it wasn't a 4 corners study/report so it didn't include hot+dry data.


UV kills most viruses... sunlight is even used to purify drinking water (SODIS). So more intense sunshine in summer (=warm weather) will slow down surface and air spread as outside surfaces exposed to UV will hinder spread. (except for "where the sun don't shine..." )

 

[NameRedacted]

Florida, California, and Texas are three large states (size and populstiion). That could skew the data.

I deliberately chose those states because they have high populations and large cities. Florida has the added 'advantage' of lots of high risk elderly people and Texas has the highest percentage of people without insurance.


Look at any of the southern states. They all seem to be less affected than the Northern states when you adjust for population density and such.

 

[NameRedacted]

I think the only temperature impact is cold weather keeps people indoors/confined spaces more. To kill viruses you gotta get temps north of something like 165F.
Supposedly hot+humid weather slows this bug down. But it wasn't a 4 corners study/report so it didn't include hot+dry data.


UV kills most viruses... sunlight is even used to purify drinking water (SODIS). So more intense sunshine in summer (=warm weather) will slow down surface and air spread as outside surfaces exposed to UV will hinder spread. (except for "where the sun don't shine..." )

I agree it may just be the amount of sunlight and not the actual air temperature.

 

[NameRedacted]

I am only speculating, but some of the countries are poor and don't have the ability to test their sick so some may be under-reporting to no fault of their own. I also wonder why Mexico and Canada are not doing as bad as the US. I think some are just not truthful and not reporting correctly.

I did think that initially but the scale of the under-reporting would have to be huge. I don't doubt that in some cases this is happening. In fact it seems certain in the case of N Korea.



For this to be true, generally, you would have to have every country in S. America, C. America, Africa, South Asia and Oceania either lying, under-reporting or a combination of both by a huge factor.


I really doubt that is true. Just look at the numbers it's really hard to find any significant S. hemisphere country that is worse off than a significant N. hemisphere country.



Of course, it could be related to travel. How many people actually travel to places like Burundi or Chad say. But there are lots of places that get multitudes of travelers from Europe, China and N America that are relatively unscathed.

 

[HF63]

Does why testing becomes very important in the fall so we can isolate any new cases.


If we assume the virus goes dormant or it hides some where, will the new cases come from oversees just like the normal flue.

 

[Sunset]

I don't think there will be a second wave.
People use that term and thinking from the 1918 Spanish flu, but that was Influenza Not Corona, two totally different viruses.

Influenza is dramatically affected by Summer weather, there is scant evidence Corona is affected.

Instead of a second wave, I see a lessening of infections due to lockdowns, and the infections will increase once lockdown is eased.

It's all semantics really.

 

[audreyh1]

I don’t think a “second wave” will wait until the fall to happen. I think we’ll get another one very soon due to restrictions being lifted. What remains to be seen is how bad it is, and how long it lasts.

 

[SteveNU]

It seems to me that there are two things at work that will dampen future waves. If we assume there is some immunity being developed and that the deaths are slowly reducing the most at risk population then aren't we effectively reducing the population density. This would seem to have more of an effect in higher population density areas where it appears that there are a higher number of previously infected who may have antibodies.

Combined with the other mitigation measures and better testing perhaps future peaks will be slower and more easily controlled?

I do have faith that people much smarter than I are working around the clock assessing and figuring this all out and as painful as it may be we will eventually work our way through this and move on.

 

[martyp]

I live in Thailand. It has been summer here but it is hot all the time. The numbers here are pretty low. Thailand never had more than 188 cases in one day and for the past couple of weeks the daily cases have been less than 20/day. I used to work in a DNA sequencing laboratory and I've listened to the health officials here and I believe the numbers of reported cases.

The virus spreads here like anyplace else. Yesterday we had 43 new cases in a border quarantine camp. Nearby Singapore has had 800+ new cases in crowded migrant living conditions. When it comes to asymptomatic transmission, the basic formula anywhere is that you have a decent chance of getting infected if you put a lot of people in a confined space for a long time. For example: if you share a living room space with an infected person and you are talking and laughing for 1-3 hours you should not be surprised if you become infected. The recent infections in meat processing plants in the US is another example of this phenomenon.

People can speculate on a statistical reduction in cases during the summer but it is always there. When they talk about a second wave they are talking about having Coronavirus at the same time as the seasonal flu. This first time the Coronavirus appeared in the US toward the end of the traditional flu season. Next year you will get them both. You may even catch both viruses. Coronavirus is somewhat more infectious and somewhat more deadly. You could estimate that you will need at least double the hospital resources next winter to handle both viruses.

 

[Clone]

The recent infections in meat processing plants in the US is another example of this phenomenon.

To add a bit more info to this, it was on the news that the Dept of Health (whatever set of initials they use today) was looking at a group of 60+ workers at one plant that were commuting from a community perhaps 80 miles away. So you have groups of people, in a car, for an extended period of time. This group probably lives with extended family and perhaps multiple families in close proximity to each other. Perfect conditions for spreading the virus.

 

[martyp]

To add a bit more info to this, it was on the news that the Dept of Health (whatever set of initials they use today) was looking at a group of 60+ workers at one plant that were commuting from a community perhaps 80 miles away. So you have groups of people, in a car, for an extended period of time. This group probably lives with extended family and perhaps multiple families in close proximity to each other. Perfect conditions for spreading the virus.

Some of the first cases in Thailand in January were cab drivers. Undoubtedly driving Chinese travelers who arrived in Bangkok for the Chinese New Year celebration. They were probably no more than an hour in the taxi.

 

[timo2]

Until there is a comparable amount of testing in each geographic area, how would a person be able to make this temperature determination?. I used to think the number of deaths could be a defacto measurement, but it turns out there is not consistent reporting of cause of death.

 

[martyp]

Until there is a comparable amount of testing in each geographic area, how would a person be able to make this temperature determination?. I used to think the number of deaths could be a defacto measurement, but it turns out there is not consistent reporting of cause of death.

People often think counting is easy. The Florida vote count in 2000 should have dispelled that notion. In any case, even with fuzzy death data, if there is going to be a reduction in virus cases in the summer that matters at all then even approximate death data will show it.

 

[Oz investor]

*** Why is Australia doing so well despite almost everyone living in cities? **

don't test , don't tell

BTW the phone app is almost ready

i guess i will use to old phone with the broken app store

i was really ill late December ( mid summer down here )

but i hadn't traveled out of state , no-one had a clue where Wuhan was and it was too early for the winter flu season , 2 months later it was just a normal pneumonia i can fix that myself and early March the medical clinics are full of sick people ( Covid , flu and measles )

,

 

[aiken]

If it is inevitable, then why did the SARS-2 virus flame out in the early 2000's? Same with swine flu.

 

[Rustic23]

I deliberately chose those states because they have high populations and large cities. Florida has the added 'advantage' of lots of high risk elderly people and Texas has the highest percentage of people without insurance.


Look at any of the southern states. They all seem to be less affected than the Northern states when you adjust for population density and such.

True, but they also have large rural areas. While I do not know Texas’s rural to metro statistics, I feel there are more people living in rural/small towns than in big cities. Population density seems to be an obvious data point.

 

[REWahoo]

While I do not know Texas’s rural to metro statistics, I feel there are more people living in rural/small towns than in big cities.

Made me look, and no surprise, the devil is in the details...

A quick calculation shows ~45% of the state's population resides in cities with a population of 100,000 or more. I saw another statistic saying that 15% of the state's population lived in rural areas. Numbers is...uh, the math says that leaves 40% (roughly 12 million) residing in towns with a population under 100K.

 

[copyright1997reloaded]

Part of the reason the new case counts are still high (a record 40K new positives yesterday) is simply because the testing capabilities keep ramping up.

For example, over 300K tests yesterday now puts us at a 7 day rolling average close to 1.5 Million/week. Three weeks ago we were averaging about 900K tests per week, and just a week ago about 1 million/week. In yesterdays results, the % positive is 13.6%, this number too has started to decline (although the number is pretty choppy). Overall all testing in the USA to date, the % positive is just under 18%.

Looking at hospitalizations, the % of positive cases requiring hospitalization has leveled off and is slightly decreasing. It seemed to peak on 4/1/2020 @ 14.8% and while not continually going down is now at 10.2%. Note that as the pressure on our medical systems lessons, the marginal decision to admit/don't admit might start to lean more towards admit (simply because they err on the side of caution given available resources).

Looking at deaths (a trailing indicator), the deaths as a percentage of positive cases still is ticking up, currently at 5.15%. However this too seems to be leveling off, for example I've had to add an extra digit (x.xx%) vs a couple weeks ago when the rate was increasing .1 to .2% per day. The deaths as a % of outcomes is also starting to drop, 34.7%, it seemed to peak in the 40-50% range over the last couple of weeks. (I also wonder in the validity of "recovered" in terms of tracking, i.e. it is a lot easier to track deaths than people who recover (w/o follow up). Certainly the "recovered" count is delayed.

Fun with numbers, here is my spreadsheet. I also provide the link to the source data I use. https://docs.google.com/spreadsheets/d/12cqet2T9DWT3nUkTu_bCffjPhbrqLz1sY29tNL5X0RU/edit?usp=sharing

 

[cathy63]

Made me look, and no surprise, the devil is in the details...

A quick calculation shows ~45% of the state's population resides in cities with a population of 100,000 or more. I saw another statistic saying that 15% of the state's population lived in rural areas. Numbers is...uh, the math says that leaves 40% (roughly 12 million) residing in towns with a population under 100K.

It's not just the populations of the towns people live in though. I live in a town of ~25K, but nobody would call it rural when we're squashed into about 2 sq miles and there's a city of 1.5M right next door.

Googling Texas urbanization turned up this gov't paper: https://demographics.texas.gov/Resources/publications/2017/2017_08_21_UrbanTexas.pdf

with this chart:

 

[Midpack]

I don’t think a “second wave” will wait until the fall to happen. I think we’ll get another one very soon due to restrictions being lifted. What remains to be seen is how bad it is, and how long it lasts.

+1. There will be a second wave, how bad depends on our collective actions, but it won't wait for or correlate strongly with winter.