Aedys Aegypti mosquito feeding. Image source: Centers for Disease Control and Prevention. 

Could we be on the verge of our next potential pandemic? Some researchers believe so as the Zika virus begins to spread well beyond the borders of Brazil and up into Central and North America.

Zika virus fears grow
The Zika virus is a type of arbovirus, meaning it's spread by insects, not from person to person. It's a virus spread by the Aedes aegypti mosquito, which incubates for between three and 12 days in humans, with statistics showing that it only tends to cause illness in about 20% of those it infects. For adults, the Zika virus tends to bring about relatively minor symptoms that can include rash, fever, headaches, and joint pain. The current major concern is what the Zika virus might be doing to pregnant women and their babies.

According to Brazil's Ministry of Health, there's been an increase of more than 20 times in the number of cases of microcephaly documented in Brazil in 2015 compared to what's considered "normal," and Zika is being blamed for that jump. Microcephaly is a rare neurological birth defect where the brain does not fully develop, resulting in an abnormally small head. Infants born with microcephaly have a higher risk of death. Brazil's government has gone so far as to recommend that women refrain from pregnancy until the disease is brought under control.

But it's not just Brazil that's concerned. Cases of Zika virus are being reported in Colombia, El Salvador, Honduras, Mexico, and now even the United States. The World Health Organization believes that anywhere between 3 million and 4 million cases of Zika virus could be diagnosed in the Americas in 2016. That's prompted the Centers for Disease Control and Prevention to warn pregnant women about traveling to Central and South American countries, as well as the Caribbean.


Image source: Flickr user Emran Kassim.

Blown out of proportion?
Based on the most recent data from Brazil's Health Ministry, up to 1.5 million of the country's citizens may have been infected, and some 4,180 suspected cases of microcephaly have been registered. Yet only 270 of those 4,180 cases have been confirmed as microcephaly. Furthermore, only six of the 270 confirmed cases have tested positive for the Zika virus.

It's because of this still-premature data that the CDC won't go as far as to confirm a link between Zika and microcephaly. The CDC has certainly suggested a possible correlation between microcephaly and the Zika virus, especially with exposure during the first trimester, but the legwork is still being done by researchers to determine if a link exists.

Image source: U.K. Department for International Development via Flickr.

We also should consider the Zika virus in terms of disease severity. Not to downplay microcephaly, but there are far more pressing concerns, based on the numbers. If there are only 270 confirmed cases in Brazil, yet 1.5 million people have been infected, we're talking about a confirmed microcephaly rate of less than 0.02% per Zika infection. By comparison, in the U.S. some 15 million to 60 million people contract the flu each year, and 36,000 of those people will die according to the Harvard Medical School. This means there's a potentially three to 13 times higher probability of dying from a flu virus than of an infant developing microcephaly from the Zika virus in any given year -- and this doesn't even account for the fact that infants have a weaker immune system and are thus more susceptible to death from the flu virus than adults.

So once again, are Zika fears being blow out of proportion? Maybe. A little perspective of the numbers should help reduce pandemic fears a bit, but it's nonetheless worthwhile for researchers to also look into possible cures for the disease.

How researchers are planning to fight the Zika virus
Currently, two different methods are being developed by biotech companies to eradicate the Zika virus.

First, as expected, there's a vaccine in development. Inovio Pharmaceuticals (INO -7.86%) has partnered with GeneOne Life Science to develop a Zika virus vaccine using Inovio's proprietary SynCon DNA-based development platform. Preclinical testing is expected to begin very soon, with human clinical trials forecast to kick off later this year if immunogenicity is determined in mice.

The other method is a bit nonconventional.

Image source: Centers for Disease Control and Prevention.

Intrexon (PGEN 0.76%) is working to reduce the effects of the Zika virus by utilizing genetically modified male mosquitos. Oxitec, a subsidiary of Intrexon that was acquired last year, has been testing these modified mosquitos in Brazil, Panama, and the Cayman Islands. The idea is that these genetically modified male mosquitos will pass along a gene to their offspring that causes them to die before reaching adulthood, thus drastically reducing the mosquito population.

The reaction of Intrexon's and Inovio's stocks recently have suggested that if a cure were discovered, it would ultimately prove very profitable. Inovio's and Intrexon's valuation rose by 36% and 18%, respectively, during the final two weeks of January.

As for me, I'm not convinced. We saw something similar happen when the idea of an Ebola epidemic was being swirled around -- and, mind you, Ebola was a disease that had a 40% mortality rate! However, organized responses from world health agencies and cross-border cooperation stifled the Ebola virus before a cure was ever discovered.

In order for a vaccine or therapy for a global virus to be profitable, it would have to be bought in large amounts by global governments, and the disease would still have to be proliferating by the time the cure was discovered. There are no guarantees that the Zika virus will even be a major concern a year or two down the road because of cross-border health agency cooperation. Plus, we're still at the point where we're waiting for official confirmation from the CDC and other global health organizations that the Zika virus is what's responsible for the rise in suspected microcephaly cases. In other words, these stocks may be just as overhyped as the media coverage has been recently.

It's definitely worth keeping an eye out for new information regarding the Zika virus, and pregnant women should indeed take precautions as suggested by the CDC. However, on the scale of potential pandemics we've witnessed in recent years, I'm not sure I'd put Zika virus in the same ballpark as Ebola, H5N1 (bird flu), or SARS.