The World Health Organization said Thursday that the Zika virus is "spreading explosively" in the Americas and that there is a high level of concern and uncertainty about the virus.

"I think everyone should be nervous," said Dr. Prabha Fernandes, the CEO of drug development company Cempra (CEMP) .

"The important message from the Zika virus is that today it could be Zika, tomorrow it could be something else. The important thing is to be prepared for many different things which could happen."

According to the WHO, the Zika virus is transmitted by some mosquitos and has been linked to an increase in birth defects. There is no specific vaccine or treatment currently available for the virus.

Dr. Fernandes said the broader issue highlighted by the Zika virus is the necessity of developing new treatments for infections caused by either viruses and bacteria. At Cempra, the focus is on development of antibiotics that fight drug-resistant bacterial pneumonia.

"This is the number one cause of death from an infection," said Dr. Fernandes, who explained the bacteria has now become resistant to at-home treatments, like Zithromax, and a person infected with the strain must be hospitalized for treatment intravenously.

"It's bad because multiple different pathogens can cause the disease. Our drug addresses all of them, and you can take it safely at home," she added.

Cempra has filed a new drug pplication with the U.S. Food and Drug Administration for its product, called solithromycin, for treatment of community-acquired bacterial pneumonia.

Dr. Fernandes is hoping that Cempra receives approval for the drug next year, and sees a big potential market for it.

Dr. Fernandes rang the closing bell at the Nasdaq on Thursday, in celebration of Cempra's 10-year anniversary.