In public health, social distancing, also called physical distancing, is a set of non-pharmaceutical interventions or measures intended to prevent the spread of a contagious disease by maintaining a physical distance between people and reducing the number of times people come into close contact with each other. It typically involves keeping a certain distance from others (the distance specified may differ from time to time and country to country) and avoiding gathering together in large groups.

By reducing the probability that a given uninfected person will come into physical contact with an infected person, the disease transmission can be suppressed, resulting in fewer deaths. The measures are used in combination with good respiratory hygiene, face masks and hand washing by a population. During the COVID-19 pandemic, the World Health Organization (WHO) suggested favouring the term “physical distancing” as opposed to “social distancing”, in keeping with the fact that it is a physical distance which prevents transmission; people can remain socially connected via technology. To slow down the spread of infectious diseases and avoid overburdening healthcare systems, particularly during a pandemic, several social-distancing measures are used, including the closing of schools and workplaces, isolation, quarantine, restricting the movement of people and the cancellation of mass gatherings.

 Although the term was introduced only in the 21st century, social-distancing measures date back to at least the 5th century BC. The Bible contains one of the earliest known references to the practice in the Book of Leviticus 13:46: “And the leper in whom the plague is… he shall dwell alone; [outside] the camp shall his habitation be.” During the Plague of Justinian of 541 to 542, Emperor Justinian enforced an ineffective quarantine on the Byzantine Empire, including dumping bodies into the sea; he predominantly blamed the widespread outbreak on “Jews, Samaritans, pagans, heretics, Arians, Montanists and homosexuals“.In modern times, social distancing measures have been successfully implemented in several epidemics. In St. Louis, shortly after the first cases of influenza were detected in the city during the 1918 flu pandemic, authorities implemented school closures, bans on public gatherings and other social-distancing interventions. The influenza fatality rates in St. Louis were much less than in Philadelphia, which had fewer cases of influenza but allowed a mass parade to continue and did not introduce social distancing until more than two weeks after its first cases. Authorities have encouraged or mandated social distancing during the COVID-19 pandemic.

Social distancing measures are most effective when the infectious disease spreads via one or more of the following methods:

• droplet contact (coughing or sneezing)
• direct physical contact (including sexual contact)
• indirect physical contact (such as by touching a contaminated surface)
• airborne transmission (if the microorganism can survive in the air for long periods); the efficacy of social distancing to contain airborne viruses compared to other measures, such as widespread mask usage, is disputed

The measures are less effective when an infection is transmitted primarily via contaminated water or food or by vectors such as mosquitoes or other insect.

Drawbacks of social distancing can include loneliness, reduced productivity and the loss of other benefits associated with human interaction.

HISTORY

Leper colonies and lazarettos were established as a means of preventing the spread of leprosy and other contagious diseases through social distancing, until transmission was understood and effective treatments invented.

1916 New York City polio epidemic

During the 1916 New York City polio epidemic, when there were more than 27,000 cases and more than 6,000 deaths due to polio in the United States, with more than 2,000 deaths in New York City alone, movie theatres were closed, meetings were cancelled, public gatherings were almost non-existent, and children were warned not to drink from water fountains, and told to avoid amusement parks, swimming pools and beaches.

Influenza, 1918 to present

During the influenza pandemic of 1918, Philadelphia saw its first cases of influenza on 17 September. The city continued with its planned parade and gathering of more than 200000 people on 28 September and over the subsequent three days, the city’s 31 hospitals became fully occupied. During the week ending 16 October, over 4500 people died. Social distancing measures were introduced on 3 October, on the orders of St. Louis physician Max C. Starkloff, more than two weeks after the first case. Unlike Philadelphia, St. Louis experienced its first cases of influenza on 5 October and the city took two days to implement several social distancing measures, including closing schools, theatres, and other places where people get together. It banned public gatherings, including funerals. The actions slowed the spread of influenza in St. Louis and a spike in cases and deaths, as had happened in Philadelphia, did not occur. The final death rate in St. Louis increased following a second wave of cases, but remained overall less than in other cities. Bootsma and Ferguson analyzed social distancing interventions in sixteen U.S. cities during the 1918 epidemic and found that time-limited interventions reduced total mortality only moderately (perhaps 10–30%), and that the impact was often very limited because the interventions were introduced too late and lifted too early. It was observed that several cities experienced a second epidemic peak after social distancing controls were lifted, because susceptible individuals who had been protected were now exposed.

 School closures were shown to reduce morbidity from the Asian flu by 90% during the 1957–1958 pandemic, and up to 50% in controlling influenza in the U.S., 2004–2008. Similarly, mandatory school closures and other social distancing measures were associated with a 29% to 37% reduction in influenza transmission rates during the 2009 flu epidemic in Mexico.

During the swine flu outbreak in 2009 in the UK, in an article titled “Closure of schools during an influenza pandemic” published in The Lancet Infectious Diseases, a group of epidemiologists endorsed the closure of schools to interrupt the course of the infection, slow the further spread and buy time to research and produce a vaccine. Having studied previous influenza pandemics including the 1918 flu pandemic, the influenza pandemic of 1957 and the 1968 flu pandemic, they reported on the economic and workforce effect school closure would have, particularly with a large percentage of doctors and nurses being women, of whom half had children under the age of 16. They also looked at the dynamics of the spread of influenza in France during French school holidays and noted that cases of flu dropped when schools closed and re-emerged when they re-opened. They noted that when teachers in Israel went on strike during the flu season of 1999–2000, visits to doctors and the number of respiratory infections dropped by more than a fifth and more than two fifths respectively.

SARS 2003

During the SARS outbreak of 2003, social distancing measures such as banning large gatherings, closing schools and theaters, and other public places, supplemented public health measures such as finding and isolating affected people, quarantining their close contacts, and infection control procedures. This was combined with wearing masks for certain people. During this time in Canada, “community quarantine” was used to reduce transmission of the disease with moderate success.

COVID-19 pandemic

During the COVID-19 pandemic, social distancing and related measures are emphasized by several governments as alternatives to an enforced quarantine of heavily affected areas. According to UNESCO monitoring, more than a hundred countries have implemented nationwide school closures in response to COVID-19, impacting over half the world’s student population. In the United Kingdom, the government advised the public to avoid public spaces, and cinemas and theatres voluntarily closed to encourage the government’s message.

With many people disbelieving that COVID-19 is any worse than the seasonal flu, it has been difficult to convince the public—especially teens and young adults—to voluntarily adopt social distancing practices. In Belgium, media reported a rave was attended by at least 300 before it was broken up by local authorities. In France teens making nonessential trips are fined up to US$150. Beaches were closed in Florida and Alabama to disperse partygoers during spring break. Weddings were broken up in New Jersey and an 8 p.m. Curfew was imposed in Newark. New York, New Jersey, Connecticut and Pennsylvania were the first states to adopt coordinated social distancing policies which closed down non-essential businesses and restricted large gatherings. Shelter in place orders in California were extended to the entire state on 19 March. On the same day Texas declared a public disaster and imposed state wide restrictions.

These preventive measures such as social-distancing and self-isolation prompted the widespread closure of primary, secondary, and post-secondary schools in more than 120 countries. As of 23 March 2020, more than 1.2 billion learners were out of school due to school closures in response to COVID-19. Given low rates of COVID-19 symptoms among children, the effectiveness of school closures has been called into question. Even when school closures are temporary, it carries high social and economic costs. However, the significance of children in spreading COVID-19 is unclear. While the full impact of school closures during the corona virus pandemic are not yet known, UNESCO advises that school closures have negative impacts on local economies and on learning outcomes for students.

In early March 2020, the sentiment “Stay The Fuck Home” was coined by Florian Reifschneider, a German engineer and was quickly echoed by notable celebrities such as Taylor Swift, Ariana Grande and Busy Philipps in hopes of reducing and delaying the peak of the outbreak. Facebook, Twitter and Instagram also joined the campaign with similar hashtags, stickers and filters under #staythefhome, #stayhome began trending across social media. The website claims to have reached about two million people online and says the text has been translated into 17 languages.

 Drawbacks

There are concerns that social distancing can have adverse affects on participants’ mental health. It may lead to stress, anxiety, depression or panic, especially for individuals with pre existing conditions such as anxiety disorders, obsessive compulsive disorders, and paranoia. Widespread media coverage about a pandemic, its impact on economy, and resulting hardships may create anxiety. Change in daily circumstances and uncertainty about the future may add onto the mental stress of being away from other people.

Effectivenes

An empirical study published in July 2020 in the The BMJ (British Medical Journal) analyzed data from 149 countries, and reported an average of 13% reduction in COVID-19 incidence after the implementation of social distancing policies.