An American Airlines Boeing 787 (front) and Delta Airlines Airbus A350 aircraft (background, obscured) wait to take off at Beijing airport on July 25, 2018. - Beijing hailed 'positive steps' as major US airlines and Hong Kong's flag carrier moved to comply on July 25 with its demand to list Taiwan as part of China, sparking anger on the island.

The rout in airline stocks continued Tuesday with American hitting a more than six-year low, leading the S&P 500 down as worries persisted about the impact of the coronavirus on travel demand. Shares of U.S. carriers were all off by more than the broader market.

United, American and Delta on Monday issued fee waivers for travelers booked on flights to South Korea, where the virus has sickened close to 1,000 people, the most outside of China, which is where most of the more than 80,000 cases have been reported. That raises concerns about the effect of the disease on travel demand beyond China. Delta on Tuesday extended waivers to three cities in Italy ⁠— Milan, Bologna and Venice ⁠— due to the outbreak there.

United on Monday also withdrew its full-year guidance of $11 to $13 a share because of the uncertainty surrounding the outbreak and its impact on "overall demand for air travel and the possibility the outbreak spreads to other regions."

American shares on Tuesday plunged 9.2% to $23.12, the lowest price on record for the company since it started trading after its 2013 merger with US Airways. United lost 6.5% to close at the lowest price since mid-2018. Delta shares fell 6.2% to end at $50.89 the lowest price since March.