Even as infections of the novel coronavirus seemed to be slowing at one point last week, the effects of the epidemic on the global tourism industry were accelerating rapidly.

The impact of the pneumonia-like disease caused by the COVID-19 virus is already being felt across Asia, where leisure and business travel contributed $884 billion to gross domestic product in 2017, the most recent year for data compiled by the World Travel and Tourism Council. (Estimates for 2018 are about $1 trillion.) For China alone, inbound tourism brought in $127.3 billion in 2019, its tourism bureau says.

But as the diagnoses tick upward again, travel agents, operators and hoteliers are bracing for months, if not a full year, of economic disruption from the outbreak, with long-term effects that may ripple well into 2021.