Insight diagram
Sike Liu's model on COVID-19 & Burnie Economy

 

This model contains three parts, the first part stimulates the COVID-19 pandemic outbreak in Burnie; the second part describes possible government policies on pandemic control; and the third part examines the possible negative impact on economy growth from those policies.


Assumptions:

1. The state boarder has already been closed and all new arrivals in Burnie need to enter a fixed period of quarantine. And the quarantine rate measures the strength of the government policy on quarantine (such as length and method).

2. Patient zero refers to the initial number of undetected virus carriers in the community.

3. Government policies such as social distancing, compulsory mask and lock down could effectively reduce community’s exposure to the virus.

4. Social distancing and compulsory mask will be triggered when COVID-19 cases reach and beyond 10 and lock down will be triggered when cases reach and beyond 1000.

4. High vaccine rate, on the other hand, could effectively reduce the exposed people’s chance of getting infected.

5. Only when vaccine rate reaches 0.6 and beyond, then the spread of COVID-19 will be significantly slowed.

6. Vaccine can’t 100% prevent the infection of the virus.

7.The infected people will need to be tested so that they could be counted as COVID-19 cases and the test rate decides the percentage of infected people being tested.

8. After people recover, there are chances of them losing immunity and the immunity lost rate measures that.

9. The COVID-19 cases could also be detected at quarantine facilities, and the quarantine process will effectively reduce the Infection and exposure rate.

10. Social distancing and compulsory mask wearing are considered as light restrictions in this model and will have less impact on both supply and demand side, and lockdown is considered as heavy restriction which will have strong negative impact on economy growth in this model.

11. In this model, light restrictions will have more negative impacts on the demand side compared to the supply side.

12. In this model, both supply side and demand side will power the economy growth.

 

Interest hints:

The vaccine could significantly reduce the spread of COVID-19 and effectively reduce the number of COVID-19 cases.

The number of the COVID-19 cases will eventually be stabilized when the number of susceptible is running out in a community (reached community immunity).

Quarantine could slightly reduce the cases numbers, but the most effective way is to reduce the number of new arrivals.

Insight diagram
This insight began as a March 22nd Clone of "Italian COVID 19 outbreak control"; thanks to Gabo HN for the original insight. The following links are theirs:

Initial data from:
Italian data [link] (Mar 4)
Incubation estimation [link]

Andy Long
Northern Kentucky University
May 2nd, 2020

This is an update of our model from April 9th, 2020. As we prepare for our final exam, I read a story in The Guardian about Italy's struggle to return to normalcy. The final paragraphs:

During the debate in the Senate on Thursday, the opposition parties grilled Conte. Ex-prime minister Matteo Renzi, who has called for less restraint in the reopening, remarked, “The people in Bergamo and Brescia who are gone, those who died of the virus, if they could speak, they’d tell us to relaunch the country for them, in their honour.”

Renzi’s controversial statement was harshly criticised by doctors who warned that the spread of the disease, which, as of Thursday, had killed almost 30,000 people in the country and infected more than 205,000 [ael: my emphasis], was not over and that a misstep could take the entire country back to mid-March coronavirus levels.

“We risk a new wave of infections and outbreaks if we’re not careful,” said Tullio Prestileo, an infectious diseases specialist at Palermo’s Benefratelli Hospital. “If we don’t realise this, we could easily find ourselves back where we started. In that case, we may not have the strength to get back up again.”

I have since updated the dataset, to include total cases from February 24th to May 2nd. I went to Harvard's Covid-19 website for Italy  and and then to their daily updates, available at github. I downloaded the regional csv file for May 2nd,  which had regional totals (21 regions); I grabbed the column "totale_casi" and did some processing to get the daily totals from the 24th of February to the 2nd of May.

The cases I obtained in this way matched those used by Gabo HN.

The initial data they used started on March 3rd (that's the 0 point in this Insight).

You can get a good fit to the data through April 9th by choosing the following (and notice that I've short-circuited the process from the Infectious to the Dead and Recovered). I've also added the Infectious to the Total cases.

The question is: how well did we do at modeling this epidemic through May 2nd (day 60)? And how can we change the model to do a better job of capturing the outbreak from March 3rd until May 2nd?

Incubation Rate:  .025
R0: 3
First Lockdown: IfThenElse(Days() == 5, 16000000, 0)
Total Lockdown: IfThenElse(Days() >= 7, 0.7,0)

(I didn't want to assume that the "Total Lockdown" wasn't leaky! So it gets successively tighter, but people are sloppy, so it simply goes to 0 exponentially, rather than completely all at once.)

deathrate: .01
recoveryrate: .03

"Death flow": [deathrate]*[Infectious]
"Recovery flow": [recoveryrate]*[Infectious]

Total Reported Cases: [Dead]+[Surviving / Survived]+[Infectious]

Based on my student Sean's work, I altered the death rate to introduce the notion that doctors are getting better at saving lives:
[deathrate] = 0.02/(.0022*Days()^1.8+1)
I don't agree with this model of the death rate, but it was a start motivated by his work. Thanks Sean!:)

Resources:
  * Recent news: "Since the early days of the outbreak in China, scientists have known that SARS-CoV-2 is unusually contagious — more so than influenza or a typical cold virus. Scientific estimates of the reproduction number — the R0, which is the number of new infections that each infected person generates on average — have varied among different communities and different points but have generally been between 2 and 4. That is significantly higher than seasonal influenza."
  * https://annals.org/aim/fullarticle/2762808/incubation-period-coronavirus-disease-2019-covid-19-from-publicly-reported
  * https://covid19.healthdata.org/italy
Insight diagram

INTRODUCTION

This is a balanced loop model that demonstrates how COVID 19 outbreak in Burnie and the response of the government (e.g. by enforcing health policies: Lockdown; quarantine, non-necessary business closure; border closure) affect the local economy.  This model has 13 positive loops and seven negative loops.  Government response is dependent on the number of reported COVID-19 cases which in turn thought to be dependent on the testing rates less those who recovered from COVID 19 and dead. Economic activity is dependent on the economic growth rate, increased in online shopping, increased in unemployment, number of people who do not obey the rules, COVID 19 cases and health policies.

 ASSUMPTIONS

 · Both infection and economic growth is reduced by enforcing government policies

 · However, the negative effect of government policies is reduced by the number of people who do not obey government health policies

 · Govt policies are enforced when the reported COVID-19 case are 10 or greater.

 ·     Number of COVID cases reported is dependent on the testing rates less those who recovered and dead.

 ·   The higher number of COVID-19 cases have a negative effect on local economy. This phenomena is known as negative signalling. 

 ·   Government policies have a negative effect on economic activity because health policies limit both social and economic activities which directly or indirectly affect the economy in Burnie .  

 ·  This negative effect is somewhat reduced by the increase in online shopping and the number of people who do not obey heath rules.

 INTERESTING INSIGHTS

The test ratings seem to play a vital role in controlling COVID-19 outbreak. Higher Rates of COVID testings decrease the number of COVID 19 deaths and number of infected. This is because higher rates of testing accelerate the government involvement (as the government intervention is triggered earlier, 10 COVID cases mark is reached earlier). Delaying the government intervention by reducing the COVID testing rates increases the death rates and number of infected. 

Increased testing rates allow the figures (deaths, susceptible, infected) to reach a plateau quickly.