(Bloomberg) -- The deadly coronavirus that has sparked stock rallies for a cluster of health companies developing drugs and screening tests reminds industry watchers of the frenzies that greeted other health scares -- and even the cryptocurrency craze.

Small-cap companies including Novavax Inc., Cerus Corp., Co-Diagnostics Inc. and Inovio Pharmaceuticals Inc. have seen shares surge this week as investors gobble up statements about their plans to help combat the outbreak. Conversations with investors, analysts and executives show many people are skeptical these products will reach patients before years of research and development, if ever.

“They just want to be able to say it in hopes that they’ll get a bump in the stock price, but I’d take anything like that with a grain of salt,” Matinas BioPharma Holdings Inc. Chief Executive Officer and co-founder Jerry Jabbour said in an interview. “It is a little bit like chasing Bitcoin and the fantastical nature of it, it captures the imagination.”

Baird analyst Brian Skorney said it’s common for companies to issue press releases every few years about “their efforts to treat some potential pandemic.” Some of these releases are just “a launch pad for generating stock moves” rather than evidence of real clinical progress, he said.

“The key to separating legitimate companies from hypesters is to see which ones are truly working with the U.S. government and other professional health organizations” and those that are “simply issuing well-timed press releases to take advantage of the situation,” said Brad Loncar, chief executive officer of Loncar Investments. He highlighted Moderna Inc.’s partnership with the National Institutes of Health and both it and Inovio getting grants from the public-private Coalition for Epidemic Preparedness Innovations.

It is worth pointing out that companies like Inovio and Novavax have ridden the wave of viral emergencies before. Novavax has touted its platform for potential vaccines for Ebola, MERS and SARS, among others, while Inovio has been tied to the development of vaccines for Ebola, Zika and MERS.

To contact the reporter on this story: Bailey Lipschultz in New York at blipschultz@bloomberg.net

To contact the editor responsible for this story: Catherine Larkin at clarkin4@bloomberg.net

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