February 11, 2016 2 min read

Two biotech companies have emerged as frontrunners in the race to develop a vaccine for Zika, a mosquito-borne virus that has affected more than 4,700 live births in Brazil and crept into 32 neighboring countries, according to a report from the World Health Organization.

Inovio Pharmaceuticals, a small Pennsylvania pharmaceuticals company, has positioned itself as one likely contender thanks to its previous work with mosquito-born diseases and its relatively quick turnaround time from concept to testing, according to Fortune.

In the past few months, investors have shown excitement about Inovio’s Zika initiative. Its stocks have surged since the company announced its bid for a vaccine last December.

Since then, Inovio has made strides toward creating a DNA-based vaccine. While the vaccine has only been tested on mice, Inovio’s CEO said the company will begin testing primates within the next few weeks. Human trials, meanwhile, could start as early as the end of the year.

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Bharat Biotech, a biotech firm based in Hyderabad, India, has been developing a Zika vaccine for more than a year. The firm started working on the virus, along with other mosquito-born illnesses, in November 2014 and has two possible vaccines -- a DNA-based version and a more traditional one that contains an inactive strain of the virus -- ready for pre-clinical trials, the company’s CEO told Reuters.

While vaccines, which require high investment and have low success rates, are risky investment bets for pharmaceutical companies, the race for a Zika vaccine is (thankfully) becoming a crowded one. Major pharmaceuticals, including France’s Sanofi Pasteur, Japan’s Takeda Pharmaceutical and U.S. pharma-giant GlaxoSmith Kline, are also exploring vaccines.

Despite these companies’ efforts, a Zika vaccine may still be years away.

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