Editor's note: This article was updated to note the correct day: Friday.

Market indices fell sharply on Friday as investors were spooked by news of a new COVID variant found in South Africa. The Nasdaq Composite and S&P 500 both slid more than 2% Friday morning as investors digested the news.

While it may be some investors' gut reaction to sell stocks, they may want to think carefully about which stocks may be good investments during times like these. Some companies may actually be able to not only navigate challenges associated with a new variant, but also have business models that could benefit from market dynamics created by consumers sheltering at home. On that note, here are two businesses that may prove very resilient if another variant gains traction around the world.

View of a castle wall from the inside.

Image source: Getty Images.

Zoom Video Communications

One of the most obvious potential winners of remote work environments is Zoom Video (NASDAQ:ZM). Unsurprisingly, the stock surged nearly 10% higher at one point Friday morning. Investors are likely betting that the company can benefit from increased investment in virtual collaboration as companies brace for more people sheltering at home around the world.

Adding to Zoom stock's attractiveness, shares have sold off sharply recently as interest in them has cooled off following a spike in 2020. Shares of Zoom are down 33% this year, taking a breather from a near-400% gain in 2020. The company's revenue growth has slowed significantly recently as Zoom faces tough year-ago comparisons and as fewer people are reliant on remote work. Third-quarter revenue increased 35% year over year. This is down from 54% growth in the second quarter. 

Zoom's top-line growth could, of course, reaccelerate if this new COVID variant becomes a serious global threat and consumers and workers start staying at home more.

PubMatic

One interesting and perhaps underappreciated tech company that is well positioned for challenging times is advertising technology specialist PubMatic (NASDAQ:PUBM). While overall advertising spend could take a hit if demand for companies' products suffers or if inventory is constrained further due to a new COVID variant, programmatic advertising specialists like PubMatic could ultimately gain market share. As an enabler of very agile digital advertising marketplaces where budgets can be easily adjusted on a whim and advertisers can quickly gravitate toward the highest return-on-investment ad products, PubMatic could see increased interest from marketers.

Further, PubMatic has no debt, is cash-flow positive, and is benefiting from surging sales recently (revenue has increased more than 50% for four quarters in a row). The company's resilient go-to-market machine, aided by the bulk of its research and development occurring offshore in the cost-saving India market and a culture that favors innovation-driven organic growth, means PubMatic has strong fundamentals for uncertain times. Its debt-free balance sheet and profitability give its business model resilience. More importantly, its programmatic-focused business model will likely gain market share in digital advertising amid a dynamic and rapidly changing ad market.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.