Someone please tell me that my math is wrong…
Seriously, I really hope my math is wrong, because if it isn’t the plain truth is that the US is in worse shape than either China or Italy with regard to Coronavirus and COVID-19.
If you are among the people wondering if we are over-reacting to the Novel Coronavirus outbreak, the answer is resoundingly no.
I’m basing all my starting numbers on the current data in Wikipedia
(which seems to be pulling numbers from each state's health and human services sites)
The Daily Rate of Spread (DRS) in the US has been over 40% for the last three days (1). In contrast Italy is holding steady around 15% (2). If we extrapolate forward with a DRS of 40% in the US and 15% in Italy the total number of confirmed cases in the US will pass Italy on Thursday, 3/26. That will also be the day we break 100,000 cases. If the reports from China can be believed they have had no new cases in three days. They are holding steady at around 81,000 confirmed cases, we will pass that on 3/25 (3).
Now here’s the bad news. Even at 15% Italy is still in horrible shape. If Italy continues from where it is today with a DRS of 15% they will reach 10% of the total population infected in 34 days, 20% in 39 days, 30% in 42 days, 40% in 44 days, 50% in 46 days, 60% in 47 days and 100% in 51 days.
So what does that mean? Italy is already seeing it’s healthcare system badly overloaded with 53,578 cases nationally. Globally the mortality rate for COVID-19 is around 4.2%. In Italy the mortality rate is 9%. The disparity is at least partially due to the overloaded medical system.
At 10% infection they would have over 6,000,000 cases. With a 9% mortality rate that is over half a million fatalities. Even if they could get the mortality rate down to the 4.2% global average it is over 250,000 dead. That is just in the first month, and that assumes the mortality rate does not increase farther as the hospitals become more and more overloaded.
Now translate that to the United States. Currently the mortality rate in the US is around 1.2%. This reflects the availability of the level of medical care required in serious cases. As hospitals start to reach and exceed capacity we can expect to see the mortality rate rise toward the global average.
According to a study conducted by the Harvard Global Health Institute (4) and then modeled by ProPublica (5) if 20% of the US Adult population is infected within 6 months most of the country will hit or exceed 100% of hospital bed capacity and some areas will exceed 200%. At 40% infection within 6 months most areas of the country exceed 200% capacity. To have any chance of current hospital capacity being able to meet the COVID-19 load in addition to normal demand the total number of cases would have to stay below 20% for 12 months and below 40% for 18 months.
Even if the US miraculously dropped to a 10% DRS starting today we would still hit 10% of the population infected in 79-80 days, 20% in 87 days, 30% in 91 days, 40% in 94 days, 60% in 98-99 days, and 100% in 104 days. At the current 40% DRS we will hit 10% in 23 days, 40% in 27 Days, and 100% in 29 Days.
If you project that into human impact, at 10% infection there are over 33 million cases in the US. Even at the current US mortality rate of 1.2% that is almost 400,000 dead. At the global average of 4.2% it is 1.3 million dead. If we were to see a mortality spike like in Italy as hospitals can’t keep up you are looking at over 2.5 million people dead. That is almost 1% of the total population. If we do not get the spread under control 60% infection nation wide is a very real possibility. 60% of the US population is over 198 million people. Even at 1.2% mortality that is over 2.3 million people dead. At 4.2% it's over 8 million. At 9% almost 18 million people. That is roughly 5% of the population. 1 in 20. Think about your family, friends, coworkers. That is probably more than 20 people. Who's not going to make it?
To stay below 20% of the population infected in the first 6 months we would have to get the DRS down to 4%. To stay below 20% for 12 months we would need to get it to 2%. To stay below 40% in 18 months we need to get the DRS below 1%.
The window to do this is very small. If we stay at 40% DRS for two more days then the target to stay below 20% infection in 12 months drops to 3% DRS.
So are we overreacting? No. If anything we are still underacting. At the current DRS or even one quarter of the current DRS even the current mortality rate will be devastating. As hospitals are stressed beyond capacity the mortality rate will only increase. If we don’t get out ahead of this and contain the spread millions will die. The CDC guidance for Preventing the Spread of Coronavirus (6) is the bare minimum we should be doing.
That’s not hype, that’s not alarmist, that’s math.
Unless my math is wrong. Someone please tell me my math is wrong.
Sources
1. https://en.wikipedia.org/wiki/2020_coronavirus_pandemic_in_the_United_States
2. https://en.wikipedia.org/wiki/2020_coronavirus_pandemic_in_Italy
3. https://en.wikipedia.org/wiki/2019%E2%80%9320_coronavirus_pandemic_in_mainland_China
4. https://globalepidemics.org/2020/03/17/caring-for-covid-19-patients/
5. https://projects.propublica.org/graphics/covid-hospitals
6. https://www.cdc.gov/coronavirus/2019-ncov/hcp/guidance-prevent-spread.html
https://www.cdc.gov/coronavirus/2019-ncov/community/guidance-business-response.html
