B. What is Defensive Isolation?

Defensive isolation is the opposite of quarantine. It isolates the healthy, rather than isolating the sick. Mitigation is the generic model. It encompasses all actions including: individual protective measures, drug treatment, vaccines, as well as quarantine, and defensive isolation.

There are far fewer studies on the effectiveness of defensive isolation. No statistical study based on the benefits from this action was found. There have been numerous studies, but they were based either on isolated anecdotal cases or on mathematical modeling.

All mathematical modeling requires numerous assumptions and the use of equations that are solvable, i.e. usually two dimensional analysis. Biology and life are never defined by or restricted by mathematical equations. They are too complicated, with literally millions of variables.

However, mathematical modeling is a valuable tool in after-the-fact epidemiology studies. This involves the use of mass data (hundreds of thousands to millions of data points) to determine general distributions and effects. The fact that smoking increases lung cancer was established using epidemiological studies.

Anecdotal means “based on personal accounts rather than facts or research.”  Many point to the experience of the Spanish Flu and how the city of Philadelphia handled the flu as compared to the city of St Louis.  They say that Philadelphia did not take any defensive action and 16,000 people died.  St Louis, on the other hand, closed schools, restricted mobility, invoked social distancing, and more.  St Louis recorded 3,000 deaths or more than 5 times fewer than Philadelphia. 

The obvious question is whether the comparison is appropriate, equal and unbiased.

1.  A single anecdotal comparison is not one based on science.  For example, the deaths in the Spanish Flu were caused mainly by bacterial infections that developed from the viral infections.  Dr. Anthony Fauci stated:

The weight of evidence we examined from both historical and modern analysis of the 1918 influenza pandemic favors a scenario in which viral damage followed by bacterial pneumonia led to the vast majority of deaths.”

Antibiotics had not yet been discovered. 

2. There were many variables not mentioned by those who cite the two cities. Philadelphia had a population of 1,832,779 and St Louis had a population of 772,807. [US 1920 Census Report]  When adjusting for population the 5 fold benefit becomes 2.2. 

  • Deaths/100,000 – St Louis…………388
  • Deaths/100,000 – Philadelphia…..872
  • Reduces 5-Fold improvement to..“2.2”

There were other differences.  Philadelphia and surrounding area was an industrial and manufacturing giant reducing the air quality.   The average annual death rate in Philadelphia was 16 deaths/1000 for the 7 years prior to the onset of the Spanish Flu. [US 1920 Census Report]  

St Louis had better air quality with an average death rate of 15 deaths/1000. [US 1920 Census Report]   This means that Philadelphia had 17,732 more deaths per year than St Louis prior to the Spanish Flu. This is natural and expected number of deaths exceeds the 16,000 quoted in the comparison.

A pre-Spanish Flu death rate adjustment based on population per 100,000 reduces the Philadelphia Spanish Flu death rate by 6.6%.  

  • Deaths/100,000 – St Louis…………388
  • Deaths/100,000 – Philadelphia…..814
  • Reduces 5-Fold improvement to..“2.0”

The population density of Philadelphia is greater than the population density of St Louis.  From the US 1920 Census, the city Philadelphia was 128 sq. miles whereas the city area of St Louis was 308 square miles.  The exact relationship between how densely people are packed together and viral spread is not established.  But, compacting people closer together makes an easier infection route.  A density adjustment reduces the Philadelphia death rate by 58%

  • Deaths/100,000 – St Louis…………388
  • Deaths/100,000 – Philadelphia…..391
  • Reduces 5-Fold improvement to…“0”

Taking into account all of the facts, the death rate in Philadelphia (doing nothing) versus the death rate in St Louise (defensive isolation) WAS THE SAME

This is not because defensive isolation has no effect.  It merely illustrates that anecdotal evidence based on two data points is unreliable.

This is not because defensive isolation has no effect.  It merely illustrates that anecdotal evidence based on two data points is unreliable.

Additionally, defensive isolation actions could actually do medical harm.  One of the few successful treatments of the Spanish Flu was “Open Air Treatment.” [Hobday & Carson, (2009) Open-Air Treatment of Pandemic Influenza, American Journal of Public Health Vo. 99 No S2 pgs 236-239]   Favorable effects were found when patients were allowed to absorb direct sunlight.  Some theorized that the ultraviolet light from the sun killed the virus. 

3.  The St Louis/Philadelphia selection could have been an arbitrary selection to support a person’s point of view.  There has been no assertion that the cities were randomly selected or that they were statistically representative. 

For example, a comparison of St Louis with Indianapolis changes the outcome.  Indianapolis (pop 314,194) is closer in population size with St Louis (772,807).  Indianapolis (372 sq miles) is closer to St Louis (308 sq miles) in density.  St Louise and Indianapolis both had the exact same pre-Spanish Flu death rates (15 per 1,000)   Most of the demographics would make the comparison between St Louis and Indianapolis a better fit.

Indianapolis did not practice defensive isolation.  They recommended and followed good hygiene.   Indianapolis experienced 90 Spanish Flu deaths. 

  • Deaths/100,000 – St Louis……………..388

  • Deaths/100,000 – Philadelphia…………28

  • Hygiene Improvement over Isolation….14

However, this does not show that hygiene is 14 times better in a pandemic than defensive isolation or doing nothing.  It only shows that Anecdotal Observations are not scientific and that the data can be manipulated by the selection method. 

Why is Quarantine so successful and Defensive Isolation not? 

The obvious answer is that defensive isolation has holes, i.e. transmission pathways, and many of them.  The Italians conducted a test of blood samples and interviewed those infected.  They found that 40% of those infected did not know they were sick.  That means there is a high degree of infections among everyone outside your home, including those who work in essential businesses.  This is like allowing infected quarantined people to work in the food industry, police, etc.  The same reasons those kinds of holes would destroy quarantine, they would and do destroy defensive isolation. 

But defensive isolation and another large hole.  It  allows  healthy individuals to leave their isolated areas at free will to mix with anyone.    In essence, defensive isolation has an almost impossible chance of success.   It is also why the actual data discussed in the subparts C and D, reveal that defensive isolation has shown no effect signal.