Will Coronavirus Pandemic Diminish by Summer? | Hacker News Reader

Will Coronavirus Pandemic Diminish by Summer?

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30 pointshello_123435 comments

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It seems to me mathematically certain that it will.

A week ago there were 170,000 cases, now there are 337,000.

337000*(337/170)^14.5 is roughly 7 billion.

14.5 weeks from now is July 1st.

So either it diminishes or it's over by July, guaranteed.

Even if it diminishes, it won't be over—it'll come back in the fall, at which point we still won't have a vaccine.

The Spanish Flu was worst the next winter...

Yeah, but that seems like a completely different situation. Wasn't the thing that happened then the dynamic where the sickest people were sent away from the front to the hospitals where they spread it, while the mild cases kept fighting?

Also, I said "or".

This is not taking into account the slowdown of spread due to containment measures.

Also not taking into account in many parts of the world there is no such thing as Flu Season.

And no one knows why.

Could you elaborate on that? Which parts?

It does. They are saying it won't continue at this rate for 15 weeks.

Either it will A or B, where A is "slows down". How is that "not taking into account the slowdown"?

You can't extrapolate the spread of viruses using an exponential function, you have to use a logistic function. Unfortunately, there isn't enough data to accurately fit a logistic function right now.

Tell that to the "shutdown the world people". The entire basis of this response is the exponential function.

With physical distancing, it may be exponential at first, but then taper off, like it did in Wuhan: https://www.calcalistech.com/ctech/articles/0,7340,L-3800632...

My mathematical intuition may not be any good, but if you are saying it will be a sigmoid type curve, would doubling the time be plausible?

But this is not in disagreement with my comment, since this would involve slowing down.

I'm not much aware of details, but it seems it's thriving here in Brazil.

Likewise in Australia. I suspect this study hints that person to person transmission is not affected but that the virus has lower viability via surface spread in hot and humid climates.

Australia is much more densely packed in Urban areas than other countries like India and in spite of favorable weather conditions the person to person transmission is high. They haven't enforced the shelter in place yet

I am very confused at the shockingly low cases in India, and the Indochina region.

Either it really is the climate or we’re talking zero testing and a fiasco that’s gonna engulf that region soon.

My theory about India, is that because of poor hygiene, anyone with a weak immune system already died from something else.

It depends on travel links with Wuhan. India is somewhere below top 10 in that list.

Perhaps because India is not testing?

If you don’t test, then you cannot confirm someone has the virus. Thus, your confirmed cases remains low.

India has not shown up on the map yet, but I suspect that the virus is picking up steam. Every week, the numbers slowly increase. And by the time someone is confirmed with the virus, then they probably already infected 10 to 20 other people.

Sorry? Australia's biggest cities are orders of magnitude less dense than Indian cities. Think 10-100x less.

While I don't know for sure what ganeshkrishnan intended, I'm going to take from the name and comment ganesh knows both countries. Perhaps what Ganesh meant is the while the population density in those Australian cities is very low, Australia has a highly urbanised population. ~11% of India's population are urbanised, 2/5 ths of australia's population is in just two cities. You hear figures for 80 or 90% of Australia's population is urbanised, but I don't have a cite.

I didn't mean the population density. I meant the density of urban vs rural spread. Australia has the world's highest urban ratio (around 96%) and extremely well connected. India is more spread out.

I think the real reason why India has a low count (for now!) is because it's a world away from China in terms of people travelling to each other while Australia is very deeply connected to Australia (students + mining export).

Where its hot and humid and positive cases are still showing up look at travel link density with China.

I guess this factor is not studied enough. Italy had significant presence of Chinese workers due to them being part of BRI.

I am in Catalunya in Spain its humid here, (not quite hot at this time of year) and we have plenty of cases.

As I understand it, hotter weather helps to prevent the progression of the disease from the upper respiratory to the lower respiratory. When the disease moves to the lower respiratory area, patients typically need hospitalization and a ventilator, and are at a much higher risk of death. If you look at the death rates in Brazil and Australia, they are lower than in the northern hemisphere. Likewise, countries with ample spare ICU beds and ventilators (like Germany) have lower death rates than countries that don't (like Italy).

Do people in Brazil and Australia use Air Conditioners? Air Conditioners reduce both temperature and humidity and make a more favorable environment for COVID-19 transmission. The use of Air Conditioners in very low in India because only the richest can afford them.

Houston has high humidity, and will make it into the 90’s this week. If this is true, it should slow down here before someplace colder, right?

I would presume that if it doesn’t, then this summer assumption is not relevant.

I think we should encourage people to turn off their Air Conditioners, especially in indoor places like malls and bars where people gather. ACs reduce both temperature and humidity and make a more favorable environment for the virus.

At the very least I hope the heat/sunlight would kill the viruses quicker when someone infected coughs on a park bench or something like that..

Heat, cold, sun, snow, and humidity don't have any effect on the virus (according to WHO). It was spreading rapidly in the Southern Hemisphere when it was Summer there.

Nytimes article: https://www.nytimes.com/2020/03/22/health/warm-weather-coron...

Some research papers from the past about SARS-CoronaVirus: https://www.ncbi.nlm.nih.gov/pubmed/22312351

From the abstract, I gather this is a solid "maybe, maybe not".

We in the southern hemisphere are heading into winter. Not ideal

I think we will only have a definite answer by May/June for this question. The close cousin of nCov, the SARS Cov-1, had started retreating back in June 2003.

An unscientific observation about "summer" is in the west, schools aren't in session. That might be a very large contributor to the spread of all viruses.

I think there are too many variables to approach this scientifically and people won't really care how it diminishes. Just do everything possible to limit the spread while scientists formulate a vaccine of sorts.

Suggesting that a seasonal change could even be considered dangerous because it may lead people to believe that containment is no longer necessary. It's only "summer" for roughly half the planet, right?

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