Here's just a sampling of the information but the article has lots of graphs which are helpful as well.
Quote:
For all of March, the world has hovered around 1.1. This translates to an average daily growth rate of 10%, with ups and downs on a daily basis. This isn’t great, but it is good news as COVID-19 most likely isn’t increasing in virality. The growth rate of the growth rate is approximately 10%; however, the data is quite noisy. With inconsistent country-to-country reporting and what qualifies as a confirmed case, the more likely explanation is that we are increasing our measurement, but the virus hasn’t increased in viral capability. Recommended containment and prevention strategies are still quite effective at stopping the spread.
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curves is the dominant trait of outbreaks. A virus doesn’t grow linearly
forever. It accelerates, plateaus, and then declines. Whether it is
environmental or our own efforts, viruses accelerate and quickly decline. This
fact of nature is represented in Farr’s law. CDC’s of “bend the curve” or “flatten the curve” reflects
this natural reality...
To
summarize, China, Singapore, and South Korea’s containment efforts worked
because community-based and airborne transmission aren’t common. The most
common form of transmission is person-to-person or surface-based...
True community spread
involves transmission where people get infected in public spaces and there is
no way to trace back the source of infection. WHO believes that is not what the
Chinese data shows. If community spread was super common, it wouldn’t be possible
to reduce the new cases through “social distancing”.
“We have never seen
before a respiratory pathogen that’s capable of community transmission but at
the same time which can also be contained with the right measures. If this was
an influenza epidemic, we would have expected to see widespread community
transmission across the globe by now and efforts to slow it down or contain it
would not be feasible,” said Tedros Adhanom, Director-General of WHO.
To summarize, China,
Singapore, and South Korea’s containment efforts worked because community-based
and airborne transmission aren’t common. The most common form of transmission
is person-to-person or surface-based.
Presence doesn’t mean
infectious. The viral concentration falls significantly over time. The virus
showed a half-life of about 0.8 hours on copper, 3.46 hours on cardboard, 5.6
hours on steel and 6.8 hours on plastic.
Due to COVID-19’s
sensitivity to UV light and heat (just like the normal influenza virus), it is
very likely that it will “burn off” as humidity increases and temperatures
rise.
Released on March 10th, one study mapped
COVID-19 virality capability by high temperature and high humidity. It found that
both significantly reduced the ability of the virus to spread from
person-to-person....
Age:
Age:
It’s
already well established that the young aren’t particularly vulnerable. In fact, there isn’t a single
death reported below the age of 10 in the world and most children who test
positive don’t show symptoms. As well, infection rates are lower for individuals below the age
of 19, which is similar to SARS and MERS (COVID-19’s sister viruses).
According
to the WHO’s COVID-19 mission in China, only 8.1% of cases were 20-somethings,
1.2% were teens, and 0.9% were 9 or younger. As of the study date February
20th, 78% of the cases reported were ages 30 to 69. The WHO hypothesizes this
is for a biological reason and isn’t related to lifestyle or exposure.
“Even when we looked at households, we did not find a
single example of a child bringing the infection into the household and
transmitting to the parents. It was the other way around. And the
children tend to have a mild disease,” said Van Kerkhove.
According
to a WSJ article, children have a near-zero chance of becoming
ill. They are more likely to get normal flu than COVID-19...
93% of people who think they are positive aren’t
Looking
at the success in S. Korea and Singapore, the important tool in our war chest
is measurement. If we are concerned about the general non-infected population,
what is the probability those who show symptoms actually test positive? What is
the chance that the cough from your neighbor is COVID-19? This “conversion
rate” will show whether or not you have a cold (another coronavirus) or heading
to isolation for two weeks. Global data shows that ~95% of people who are
tested aren’t positive. The positivity rate varies by country.
Based on the initial
results and the results from other countries, the total number of positive
COVID-19 cases will increase as testing increases, but the fatality rate will
continue to fall and the severity case mix will fall.
In general,
the size of the US population infected with COVID-19 will be much smaller than
originally estimated as most symptomatic individuals aren’t positive. 93% — 99%
have other conditions.
Globally, the US has a
long way to go to catch up in testing. As testing expands, the total number of
cases will increase, but the mild to severe case ratio will decline
dramatically.
1% of cases
will be severe
Looking at the whole
funnel from top to bottom, ~1% of
everyone who is tested for COVID-19 with the US will have a severe case that
will require a hospital visit or long-term admission.
~Source and full article with all data
~Source and full article with all data
