COVID-19/Efficacy of lockdown
In epidemiology of communicable diseases the contact between infected and suceptible is key for risk mitigation as long as vaccination and/or widely available drugs are available.
Contact and Contact Rates[edit | edit source]
"Contact" between humans includes different meanings: First of all we think about:
- meeting people,
- shake hands and
- hug friends.
But it includes also non direct contact:
- a large group of people leave the room and
- a few minutes later a next group will enter the room (aerosol transmission)
So contact is not only dependent on spatial distance but also on means to connect people even if the people do not recognize that they met. The connectivity between those groups is also dependent on where the groups met inside a room or outside and how they protect themselves. If the are singing or just sitting and if they keep spatial distance of 2m between them.
Logic of Contact Rate and Infection[edit | edit source]
The number of people that you meet is one indicator for the risk and one element of risk mitigation. Consider the contact rate as the lanes of the highway. High contact rates between humans does not mean that there is immediately a high number of infections but it provides the routes for the virus to enter a community much quicker. Comparing that with the example of traffic:
- if you have many lanes on the highway, then the cars can commute much quicker in and out of the city,
- if you have a narrow curved road with just one lane, traffic flows slowly and it takes longer until a fixed number of cars will reach the city center.
The efficacy of lockdowns imposed by governments can be investigated. What can be investigated is the statistically measurable impact of lockdowns on relevant outcomes such as mortality rate.
Use the following resources with caution.
Further reading in mainstream media (use with double caution: mainstream media is generally unreliable on science):
- Williams, Sophie (3 January 2020). "How the plague taught us to fight coronavirus". BBC News.
- Levenson, Michael (2 January 2020). "Scale of China's Wuhan Shutdown Is Believed to Be Without Precedent". The New York Times.
- Rogers, Adam (22 January 2020). "Would the Coronavirus Quarantine of Wuhan Even Work?". Wired.
- Du, Lisa (24 January 2020). "China's Unproven Antiviral Solution: Quarantine of 40 Million". Bloomberg L.P.
- "As Coronavirus Fears Intensify, Effectiveness of Quarantines Is Questioned". The New York Times. 2 January 2020.
- Hamblin, James (2 January 2020). "A Historic Quarantine". The Atlantic.
- Jain, Vageesh (31 January 2020). "Coronavirus outbreak: quarantining millions in China is unprecedented and wrong". The Conversation.
Further reading for science, including pre-prints:
- Full lockdown policies in Western Europe countries have no evident impacts on the COVID-19 epidemic. by A. J. Meunier, May 1, medrxiv.org - non-peer-reviewed preprint of a study
- A country level analysis measuring the impact of government actions, country preparedness and socioeconomic factors on COVID-19 mortality and related health outcomes, July 21, 2020, thelancet.com
- The above investigation included look at correlations of obesity, median population age, GDP, time to border closures from the first reported case, and more.
Further reading on media that neither scientific publication venue nor mainstream media, to be used with double caution:
- Lockdown Deaths, Not Covid Deaths by Iain Davis, July 14, ukcolumn.org
Other further reading:
- COVID-19 pandemic lockdowns, wikipedia.org