Visualising Hong Kong’s biggest Covid-19 super-spreader event by Marcelo Duhalde

In the middle of the Covid-19 pandemic, a major contagious outbreak occurred, forcing the authorities to take restrictive measures for the population, such as the closure of schools, bars, and restaurants to reduce the risk of infection, seriously affecting the business of goods and services and therefore the economy of Hong Kong.
Attending dance clubs is a deep-rooted tradition, especially among women over 40 years of age. These are places of high capacity, where there is an orchestra, singers, dance instructors, waiters, etc. There is a vast network of dance venues in Hong Kong, including clubs, studios, restaurants, banquet halls and private establishments. People can visit these places without special restrictions.
When tracing positive cases, it was discovered that many attendees visited several establishments in a short time (less than a week) helping to spread the virus among those attendees to premises who in turn visited other clubs infecting more people.
In this piece, the challenge was to locate the cases and describe a temporal and spatial connection between the affected venues. People who visited up to 5 places were assigned a thicker line on the graph and those who visited only two a thinner line.
With this system of progressive connections, the magnitude of contagion among the public can be understood, each infected person represents a risk factor because many asymptomatic cases after visiting the clubs infected more people in their family environments.
The connection chart was created using adobe illustrator and java script libraries.
Other visual explanations were included to complement the main information. The sankey diagram reveals the age ranges and the gender of the main spreaders of this event that meant a wave of infections and confinements that affected the city.