With the confirmation of at least 10 cases of the coronavirus, Macau announced that it will close all casinos in the Chinese territory for 15 days.
There have been over 20,000 confirmed cases of the coronavirus as of Monday. Hong Kong reported its first fatality from the virus, which has killed at least 425. All but two of the deaths occurred in mainland China.
Outside of China, more than 170 confirmed cases have been reported in more than 20 nations.
In the United States there have been 11 confirmed cases of the virus, with 6 of them coming from California.
The World Health Organization (WHO) declared a public health emergency of international concern last week. The United States, along with a number of other countries started evacuating their citizens on flights from Wuhan, the capital of Hubei province in China where the virus was first detected.
U.S. gaming stocks took a big hit in pre-market trading Tuesday after authorities in China announced the casino closures. Macau is the biggest gambling destination in the world.
Macau's casinos had revenue of six times that of Las Vegas, the worlds' second biggest gambling location.
According to Macau Chief Executive Ho Iat-Seng the closure could last "for months" if the situation were to worsen, and said that they have discussed possible border shutdowns with the neighboring prefecture city of Zhuhai.
Wynn Resorts (WYNN LAS VEGAS) , which generates around 70% of its earnings from Macau gaming, was marked 2.8% lower in premarket trading at $125.00 each, while rival Las Vegas Sands Corp (LVS) - Get Report, with around 60% Macau earnings exposure, was seen 3.8% lower at $64.03 per share. MGM Resorts International (MGM) - Get Report, meanwhile, were marked 3.25% lower at $30.20 each.