Even though modern medicine has advanced in ways that were unfathomable 100+ years ago, when it comes to limiting the spread of contagious disease, the main tools are old school: Social Distancing, Isolation, and Quarantine. In the absence of a vaccine or effective antiviral medications, prevention of the spread of infectious disease relies on breaking the chain of human-to-human transmission.

Social Distancing: “Social distancing is designed to reduce interactions between people in a broader community, in which individuals may be infectious but have not yet been identified hence not yet isolated. As diseases transmitted by respiratory droplets require a certain proximity of people, social distancing of persons will reduce transmission.”

Isolation: “Isolation is the separation of ill persons with contagious diseases from non-infected persons to protect non-infected persons, and usually occurs in hospital settings.”

Quarantine: “Quarantine separates and restricts the movement of people who have been exposed to a contagious disease to see if they become sick. It lasts long enough to ensure the person has not contracted an infectious disease.”

Source for three definitions: Isolation, quarantine, social distancing and community containment: pivotal role for old-style public health measures in the novel coronavirus (2019-nCoV) outbreak

As of right now, the thing that is within our individual power for those of us who are not sick or exposed is social distancing. The goal of social distancing is not only just keeping yourself from getting infected, but also to help stop the person-to-person transmission of the illness more broadly through the community. Social distancing is a key tool in “flattening the curve” of the spread of the disease which can reduce the number of infected people and also keep a surge of sick people from overwhelming the health care system.

It is very important to understand that there are actions we need to take as a community to limit the spread of the virus that goes way beyond whether or not we’re concerned for our own health. If you are thinking about taking a trip or attending a conference only part of the consideration is your own health; with a pandemic, an issue is also whether your actions lead to the virus spreading among your friends, family, co-workers and the broader community.

A great example is the difference in the spread of the Spanish Flu in Philadelphia vs. St. Louis in 1918. In Philly they went ahead with a planned parade and did not cancel public events. In contrast in St. Louis the city leaders “closed schools, playgrounds, libraries, courtrooms, and even churches. Work shifts were staggered and streetcar ridership was strictly limited. Public gatherings of more than 20 people were banned.” Source. The decision to shut down so many activities in the city was not popular and the city leaders were lambasted for overreacting. But, their actions saved lives: the chart shows the death rate from the Flu in the two cities:

COVID-19 is spread exponentially and as venture capitalist Paul Graham of Y Combinator has stated: “When you’re dealing with exponential growth, the time to act is when it feels too early.”

We do not need to panic, but we should start social distancing immediately in order to arrest the spread of the virus. The best time to start social distancing is BEFORE there are reported outbreaks in your community because, as the first two articles below explain, the official count of infection runs pretty far behind the actual spread of the virus.

Here are a few must-read articles on this topic:

Coronavirus: Why You Must Act Now (I cannot recommend this article highly enough)

Cancel Everything: Social distancing is the only way to stop the coronavirus – we must start immediately

Stream of tweets from an Italian doctor about what is happening to the health care system in Italy (This could be what happens in the U.S. unless we all take drastic steps).

Finally. Don’t panic. Wash Your Hands. We’ll get through this.

IFOD on the coronavirus and how epidemics spread