U.S. markets are heading for their worst week since the financial crisis with the final tally of economic damage from a spreading virus still unknown.

That doesn’t mean there isn’t potential promise in a select group of companies, either because their stocks have been beaten up so badly in recent days, or because their products may be needed to combat the novel coronavirus.

On Friday, companies continued to issue warnings about weaker sales as the outbreak shuts down industrial centers, empties shops and restricts global travel.

Here’s a look at some of the companies that steered clear of, or emerged from the fray on Friday:

Health Companies

Shares of vaccine maker Novavax Inc. (NASDAQ: NVAX) rose more than 35% Friday, while others in the sector — like Gilead Sciences (NASDAQ: GILD) and Co-Diagnostics (NASDAQ: CODX) — are experiencing pullbacks. Novavax announced earlier this week that it was starting animal testing for its vaccine candidates for the virus. Shares of Allied Healthcare Products Inc. (NASDAQ: AHPI) more than doubled. The company makes respiratory health products that are in short global supply.

Cruise Operators

Perhaps no other group has been damaged more than cruise operators with a nightmare narrative emerging from the Diamond Princess, a ship that docked in Japan with 3,700 people aboard. They were all quarantined when one passenger who had disembarked tested positive for the virus. Infections spread across the ship, eventually afflicting 700 passengers and crew.

Shares of cruise operators plunged 30% or more as shipboard infections rose. It was a different story Friday, with some on Wall Street believing that the sell-off was overdone.

Shares of Royal Caribbean Cruises Ltd. (NYSE: RCL) rose 4.4%, while Norwegian Cruise Line Holdings Ltd.’s (NYSE: NCLH) stock gained 7,2%. Carnival Corp.’s (NYSE: CCL) stock climbed 4.9%.

Chip Makers

Another hard hit sector is computer chip makers with extensive production facilities in China. However, recognizing that the viral outbreak will end eventually, Wall Street overcame its fears and vaulted some companies out of the danger zone by reassessing fundamental performance.

Advanced Micro Devices (NASDAQ: AMD) is one of the companies with high exposure to China, but it posted solid fourth-quarter financials in its most recent quarter and has been holding its own against bigger rivals. The stock rose 3.3% Friday and has climbed more than 10% since the start of the year.

Nvidia Corp. (NASDAQ: NVDA) is benefiting from strong revenues and profits in the fourth quarter as well. Also, Nvidia makes graphics chips for gaming and artificial intelligence. What better way to ride out a quarantine than gaming? Its stock gained 6.9% Friday.

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