PARIS — Twice a year, the luxury fashion houses of the world present their ready-to-wear clothing for the coming season. This creates an international traveling circus of retailers and reporters, high-spending customers and Instagram influencers, executives and a small army of public-relations professionals, many traveling from New York to London to Milan and finally to Paris.

This year, the caravan’s arrival in Milan in mid-February intersected with an outbreak of Covid-19, the new coronavirus, in Italy, then the country worst hit by the illness outside of Asia.

And so, a thousand or so very well-clad people wondered for a few weeks: Would they become a global public health menace, a vector of transmission from the elite front rows of fashion shows to the world at large?

The final leg of this monthlong tour arrived for a week in Paris starting on Feb. 24. On the first day of shows, the number of reported cases of coronavirus in France was just 14; by the last day, there were more than 200, and the country had banned gatherings of more than 5,000 people in confined spaces.