The Anatomy of a Pandemic

Why Outbreaks like Coronavirus Spread Exponentially, and How to “Flatten the Curve”

After the first case of covid-19, the disease caused by the new strain of coronavirus, was announced in the United States, reports of further infections trickled in slowly. Two months later, that trickle has turned into a steady current.

This so-called exponential curve has experts worried. If the number of cases were to continue to double every three days, there would be about a hundred million cases in the United States by May.

That is math, not prophecy. The spread can be slowed, public health professionals say, if people practice “social distancing” by avoiding public spaces and generally limiting their movement. Read More

The Korean Clusters: How Coronavirus Cases Exploded in South Korean Churches and Hospitals

South Korea announced thousands of coronavirus cases in the space of only a few days in late February. The surge in cases centred mostly around one main cluster from a church in Daegu city. The outbreak initially pushed South Korea’s tally of confirmed cases much higher than anywhere else outside of China and cases there have continued to rise since.

The virus was first confirmed in the country on Jan. 20 when a 35-year-old Chinese woman who flew from Wuhan, China to Incheon international airport, which serves Seoul, was isolated upon entry into the country. In the four weeks following the incident, South Korea managed to avoid a major outbreak with only 30 people contracting the virus, despite many interactions between those later confirmed as being sick and hundreds more people being identified as contacts of the sick patients.

This changed with the emergence of “Patient 31.” Read More

Can You Become Immune to the Coronavirus?

As the number of people infected with the coronavirus surpasses 450,000 worldwide, and more than 1 billion are locked in their homes, scientists are wrestling with one of the most pressing questions of the pandemic: Do people who survive the infection become immune to the virus?

The answer is a qualified yes, with some significant unknowns. That’s important for several reasons.

People who are confirmed to be immune could venture from their homes and help shore up the workforce until a vaccine becomes available, for example. In particular, health care workers who are known to be immune could continue to care for the severely ill.

Growing immunity in the community also is the way the epidemic ends: With fewer and fewer people to infect, the coronavirus will lose its toehold and even the most vulnerable citizens become more insulated from the threat.

Immunity may also bring an early treatment. Antibodies gathered from the bodies of those who have recovered may be used to aid those struggling with the illness caused by the coronavirus, called COVID-19. Read More