A Monday sell off across the stock market on COVID-19 Delta variant fears hit cruise operator stocks.

A near six-week downturn in cruise line stock prices accelerated on Monday, as Carnival Corporation shares were down just over 5.5 percent by early afternoon, to $19.70 per share, off a 52-week high of $31.52.

Royal Caribbean Cruises was off nearly 5 percent, down to just below $69.00, off a 52-week high of $99.24.

Norwegian Cruise Line Holdings was down over 5.5 percent as well, trading at $21.80 in the early afternoon, down from a 52-week high of $34.48, which was hit in June.

Lindblad Expeditions fared a bit better, and was only off 2.8 percent, down to $11.78, but off its one-year high of $21.91 from February.

Despite the sell off, J.P.Morgan was bullish on the cruise sector in an investor note sent out on Friday July 16.

“We don’t see the recent inflection in global COVID-19 case counts materially impacting the industry’s ongoing restart mainly given the well-documented lack of incremental severity of the delta strain, and yet cruise shares now sit ~10% below early December 2020 levels on average, a time when the realization of vaccinated masses was still a long way off, more equity capital raising was on the come, and visibility was low for a resumption of U.S. revenue sailings as well as a significant recovery in bookings,” the investment bank said, in a note sent to clients.