Social distancing: An overview
Social distancing or physical isolation is a set of non-medical anti-infection control measures aimed at stopping or slowing down the spread of communicable diseases. The purpose of social distancing is to minimize the chance of contact among persons who are infected due to a virus outbreak and others who are not to play down disease transmission and the rate of mortality. Social distancing is most beneficial when the infection can be transmitted by direct communication through an invisible droplet (sneezing or coughing); direct and indirect physical contact (e.g. by having to touch a contaminated object like a door handle); or airborne transmission (if the microorganism can sustain in the air for a considerable length of time). Social distancing may be less successful in cases where the microorganism can survive in the air for a longer period.
The disadvantages of social distances may include solitude, lower productivity, and the loss of other advantages related to human interaction. Historically, leprosy colonies had been maintained as a means of preventing the spread of leprosy and other serious diseases through social distancing until comprehended and subsequently, was ways of effective treatments were developed. From the viewpoint of epidemiology, the basic objective behind social distancing is to reduce the elementary reproduction number, which is the average number of secondarily infected persons derived from one primary infected individual inhabitant where all individuals are uniformly susceptible to disease. In the fundamental model of social distancing, where a percentage of the population participates in social distancing in order to reduce their relational contact to a fraction of their normal contact. For instance, a reduction of 25% of the social contacts of the masses to 50% of their normal level provides an effective reproduction figure of about 80% of the fundamental reproduction number. A seemingly small reduction has a profound effect on delaying the rapid growth and spread of the disease.
A spreading disease can lead to a change of behavior amidst people deciding to stay away from public places and their companions. When enforced to control epidemics, social distancing can result in benefits but it could be expensive. Research shows that the measures need to be applied intensively and immediately to be productive. In Philadelphia and St. Louis, during the flu pandemic of 1918, US authorities introduced bans on public meetings, school closures, and other social distancing initiatives, but in Philadelphia the five-day lagging in implementing these steps caused transmission rates to increase three to five times, while in St. Louis, a more prompt response was effective in reducing the intensity of the disease.
During the 1918 epidemic, Bootsma and Ferguson surveyed social distancing initiatives in nearly 16 U.S. cities and noticed that time-bound initiatives only marginally decreased overall mortality rate (maybe 10–25%) and that the effect was mostly very negligible because the interventions were implemented too late and lifted too early. It was found that some cities experienced an outbreak after social distancing restrictions were lifted, causing exposure of susceptible individuals who had been covered since then were exposed.