Global share markets surged this week on news that an American biotechnology firm had made significant progress on a coronavirus vaccine.

Is this the silver lining in the coronavirus pandemic that investors have been hoping to see? It’s too early to say.

There’s no mistaking the good news: The Nasdaq-traded Moderna issued a press release Monday claiming that its experimental coronavirus vaccine showed promising results in an early-stage trial. The vaccine produced antibodies in all 45 study participants, raising optimism that researchers are getting closer to neutralizing the disease.

The news sent Moderna’s stock soaring 25% on Monday, a rally so rich that the company offloaded billions in shares the very next day to fund its vaccine research.

It should be noted that Moderna’s early vaccine results in no way suggest that a comprehensive treatment is coming. For starters, the sample size is too small to make any definitive conclusions and more rigorous “phase 2” and “phase 3” trials are needed.

“This is just the very beginning of the clinical work,” said Dr. Barney Graham of the vaccine-research centre at NIAID.

Currently, there are more than 100 coronavirus vaccines being developed worldwide, according to The Wall Street Journal.

Investors’ exuberance towards promising vaccine results is understandable, but the Moderna news is another example of putting the cart before the horse. Investors should also be carefully weighing conflicting reports about a possible virus mutation in China.

Chinese health officials are claiming that subsequent Covid-19 outbreaks have differed from the initial wave of infection. As Bloomberg reports, there’s some evidence that “the pathogen may be changing in unknown ways and complicating efforts to stamp it out.”

We’re not out of the woods yet. With more than 5 million reported cases around the world, coronavirus will be with us for a very long time. At some point, it’s reasonable to expect that the stock market will begin to mirror the grim economic realities facing the globe.