# Spatial distancing

Distant people standing in line in Spain (2020)

The spatial distancing , also spatial separation or physical distancing ( English : physical distancing ; often the term social distancing is also used, which incorrectly reflects the concern ), includes a number of non- pharmaceutical measures for infection control , which stop or stop the spread of a contagious disease should slow down. The aim of the measures is to reduce contact between people and, through the safety distance, the number of infections, for example through droplet infections, to reduce.

Alternatives to flattening the epidemic curve.
This graph shows how lack of contact with a single infected person can prevent dozens of outbreaks with the exponential spread of disease.

The English term social distancing, which is also used in German-language media, or “social distancing” ( social distance ) translated into German are misleading, as this implies that people should keep a social distance from one another. However, it is not about social isolation of individuals, but about spatial distancing from (possibly) infected to non-infected people.

## Mathematical theory

The mathematical basis that leads to the recommendation of spatial distancing is the base reproduction number . This represents the average number of other people infected by one person and is different for each type of infection - for HIV , for example, it is much smaller than for COVID-19 . The number also does not differentiate between sick and healthy, among other things, but assumes a uniformly susceptible population to infection. A mathematical model can now be used to calculate the effect of spatial distancing for the respective type of infection. ${\ displaystyle R_ {0}}$

In the formula below, the proportion of those who adhere to the distance rule denotes the fraction of interpersonal contacts compared to the normal case and provides the number of reproductions influenced in this way. ${\ displaystyle f}$${\ displaystyle a}$${\ displaystyle R}$

${\ displaystyle R = \ left (1- (1-a ^ {2}) \ cdot f \ right) \ cdot R_ {0}}$

Example: If every fourth person ( = 25% = 0.25) limits their social contacts to half ( = 50% = 0.5), then the transmission rate drops from the original 100% to 81%. In the case of subsequent infections, this minimally effective reduction has a considerable impact on the speed at which the infection spreads. ${\ displaystyle f}$${\ displaystyle a}$

## Purpose and functionality

Alternative forms of greeting without physical contact in practice (here: the traditional greeting in Taiwan )

The goal of spatial separation is to reduce the likelihood of contact between people carrying an infection and others who are not infected in order to minimize disease transmission , morbidity and ultimately mortality .

It is practiced in everyday life, in particular, by keeping physical distance and avoiding physical contact (at least 2 meters away, no shaking hands , kissing, etc.) and speaking little. However, permanent spatial isolation is the most effective means of minimizing the risk of - even indirect - interaction with potentially infected people and thus the risk of infection. This can be implemented for working people in the form of teleworking (home office) . Quarantine is considered an extreme degree of spatial distancing .

Spatial distancing has an influence on infections caused by droplet infection (e.g. by coughing , sneezing or speaking ), by direct body contact , by smear infection (e.g. by touching a surface contaminated with viruses or other microorganisms ) or through the air are transmitted via aerosols . In the event of epidemics or pandemics with the above-mentioned transmission routes, it is recommended that medical mouth and nose protection or an everyday mask are unavoidable in places where other people are located .

## Historical

One of the earliest references to spatial distancing dates back to the seventh century BC. In the book of Leviticus , 13.46: “And the leper in whom the plague is […] he will dwell alone; [outside] the camp will be his home. "

Historically, leper colonies and isolated hospitals were set up to make the spread of infectious diseases more difficult through physical distancing. In order to spatially separate the seriously ill people from the rest of the population, "infirmaries" such as leprosy houses or plague houses were built far outside the cities. When they understood the transmission paths in modern medicine and effective for some infectious diseases treatments were provided, you could see the physical isolation of new measures such as the establishment of isolation rooms guarantee.

## COVID-19 pandemic

Information signs and markings for spatial distance at a discount store in mid-March 2020
Japan's ambassador Kinefuchi steps down an
honor formation in East Timor . Because of COVID-19, there are fewer soldiers who also keep a greater distance from one another (2020).

In the course of the beginning of the COVID-19 pandemic in spring 2020, the appeal Flatten the curve! (English for: "flatten the curve!"); it is based on the graphical representation of the course of the epidemic and stands for the goal of slowing down the rate of spread of the epidemic in a certain area (country, state, region) by means of spatial distancing. Figuratively speaking, the number of infected people should be stretched over a longer period of time so that the number of infected people requiring treatment does not exceed the capacity of the hospitals in this area. This capacity is limited on the one hand by the availability of beds and specialist staff, on the other hand - as in this case with pneumonia - mainly by the number of intensive care units with ventilators . The importance of spatial distancing highlight to control COVID-19 pandemic, and to anchor it in the consciousness of the population, the German launched Federal Ministry of Health Campaign # WirBleibenZuhause what a great response in the media , social media and celebrities came . According to a representative survey, at the end of March, before the politically ordered ban on contact, the Germans had reduced their physical social contacts to an average of around a quarter of the level before the pandemic. Around half of those surveyed did this out of self-protection, 30 percent to protect friends and family and 18 percent to protect others. An economically optimal regulation of the spread of the virus for Germany would go beyond this voluntary contact restriction, significantly further reduce contacts in order to keep the infection rate down to a low level and then stabilize at this level with significantly more contacts again.

Commons : spatial distancing  - collection of images, videos and audio files

## Individual evidence

1. Why The WHO Is Now Using The Phrase "Physical Distancing" Instead Of "Social Distancing"
2. New Study Estimates Effects of Physical Distancing on Progression of COVID-19 Epidemic. In: sci-news , March 26, 2020
3. ^ German technical term for social distancing according to the German translation in On the preparedness and response planning of the European Community with a view to an influenza pandemic of the EU Commission of November 28, 2005.
4. ^ Siouxsie Wiles: After 'Flatten the Curve', we must now 'Stop the Spread'. Here's what that means . March 14, 2020. Accessed March 13, 2020.
5. RM Anderson, H. Heesterbeek, D. Klinkenberg, TD Hollingsworth: How will country-based mitigation measures influence the course of the COVID-19 epidemic? . In: The Lancet . March 2020. doi : 10.1016 / S0140-6736 (20) 30567-5 . PMID 32164834 .
6. Physical instead of social distancing - people should stay in contact. In: n-tv.de , March 30, 2020
7. ^ Niels Becker: Modeling to Inform Infectious Disease Control . CRC Press , 2015, ISBN 978-1-4987-3107-2 , p. 104.
8. ^ Information about Social Distancing. (PDF) Public Health Department of the Santa Clara Valley Health & Hospital System, accessed March 21, 2020 .
9. ^ Harry Stevens: Why outbreaks like coronavirus spread exponentially, and how to “flatten the curve”. In: washingtonpost.com. March 14, 2020, accessed on March 21, 2020 .
10. a b CDC: Coronavirus Disease 2019 (COVID-19). February 11, 2020, accessed April 10, 2020 (American English).
11. CC Leung, KK Cheng, TH Lam, GB Migliori: Mask wearing to complement social distancing and save lives during COVID-19
12. #wirbleibenzuhause. Federal Ministry of Health, accessed on March 24, 2020 .
13. Martin F. Quaas, Jasper Meya, Hanna Schenk, Björn Bos, Moritz A. Drupp: The Social Cost of Contacts: Theory and Evidence for the COVID-19 Pandemic in Germany . In: SSRN Electronic Journal . 2020, ISSN  1556-5068 , doi : 10.2139 / ssrn.3606810 .
14. ^ The Social Cost of Contacts: Theory and Evidence for the COVID-19 Pandemic in Germany. Retrieved July 1, 2020 .
15. Julia Köppe, DER SPIEGEL: Corona: Voluntary contact restrictions could probably have contained the pandemic - at a high price - DER SPIEGEL - Wissenschaft. Retrieved July 1, 2020 .