Pandemic plays are out and reopening plays are in, but the staying power of the equity market's latest trend will largely depend on the viability of a vaccine.

On Nov. 9, Pfizer Inc. and BioNTech SE announced that an investigational coronavirus vaccine was more than 90% effective in preventing infection, causing stock sectors battered since March to skyrocket and many of those that have outperformed amidst the global pandemic to dip.

Oil and gas companies, banks, airlines and cruise lines all climbed, while online retailers, virtual communications companies and home workout stocks all fell.

Amazon.com Inc., for example, which climbed nearly 76% from the start of March to Nov. 6, tumbled nearly 8% following the vaccine news Nov. 9. Meanwhile, EPR Properties, which fell about 60% since the start of the pandemic, jumped more than 44% that day.

"Groups that have been decimated all year registered double-digit gains from 10 to 50%," said Michael O'Rourke, chief market strategist at JonesTrading. "In short, it was a notable rotation from growth to value. This rotation is just getting underway."

Since the start of March, when the effects of the global pandemic began seizing markets, growth stocks, led by big tech names, mostly climbed, peaking at a nearly 30% gain by Sept. 2, when the S&P 500 reached a then-record high. Over the same time, value stocks, characterized by prices that seem to lag fundamentals, fell by about 1.2%.

But the paths of these stocks appear to have reversed following the Pfizer announcement, as the S&P 500 value index climbed 5% by the close Nov. 11 while growth stocks dipped by 0.2% over the same time, due to a combination of the vaccine news and a more positive outlook on the U.S. economy.

"Investors finally seem happy to rotate out of the work-from-home plays in the tech sector, and into stocks that rely on economic growth, which had underperformed during the post-lockdown melt-up," said Fawad Razaqzada, a market analyst with ThinkMarkets.

In a Nov. 11 note, David Kostin, chief U.S. equity strategist at Goldman Sachs, forecast the S&P 500 to jump 16% by the end of 2021, partly on the expectation that at least one vaccine is approved by the U.S. Food and Drug Administration.

Kostin wrote that investors should take positions in value stocks "that benefit from the vaccine and economic normalization."

The S&P 500 settled at a new all-time high of 3572.66 on Nov. 11, up 9.2% on the month. The large-cap index has increased by 1.8% since Pfizer's vaccine announcement.

The Nasdaq closed at 11,786.43 on Nov. 11, up 8% on the month, despite falling 1.4% on Nov. 9-10 after the Pfizer announcement.

Some equity analysts said it remains unclear whether investors have begun to truly recalibrate their positions or if the market will continue to ebb and flow on similar vaccine news.

"One swallow does not make a summer, and there still remains a some way to go before life as we knew it a year ago, can return to any semblance of normal, in the short or medium term," Michael Hewson, chief market analyst at CMC Markets, said in a Nov. 10 note.

Vaccine trial data still needs to be parsed, further lockdowns remain likely, and distancing restrictions will likely remain in place well into 2021.

"This means that for all of the optimism that we saw in [the Nov. 9] rebounds in travel, leisure, pubs, restaurants and other hospitality, we need to see evidence that consumer behavior will start to change as well," Hewson said. "Even then, overall capacity in all of these sectors is likely to be much lower than was the case pre-pandemic."

Peter Cecchini, CEO and founder of AlphaOmega Advisors, took an even more bearish view, claiming that little has changed in terms of economic recovery following the vaccine news. He pointed out that the duration of a vaccine's immunity remains unknown, long-term refrigeration needs present a high hurdle for distribution, and large-scale immunizations are still months away even if a vaccine is approved soon.

"The retail investors in control of this market have no context," Cecchini said. "They will stay in control of the vehicle until it finally swerves off the road."