The Rise of Zika

By Drs. David Niesel and Norbert Herzog, Medical Discovery News

Have you noticed in the past few years, we seem to be continuously assaulted by microbial menaces? Some years back it was SARS, which set off a global panic. People were screened for fevers at many major international airports. Then came the West Nile virus, which started from a single case in New York and in a matter of years marched across the U.S. Who can forget the avian flu or swine flu, which happened around the same time? More recently, the MERS virus has emerged, with outbreaks in the Arabian Peninsula and then whole villages in Korea. We are just now reaching the end of the devastating Ebola outbreak in West Africa. Even if you're not an alarmist, it's hard to ignore the threat of these new microbial menaces.

The latest is one that we are beginning to know well is Zika. While it sounds like the name of a modern Scandinavian rock band, this virus was first isolated in 1947 in Uganda. It emerged in the Pacific Islands before it spread to Brazil, and it's rapidly spreading through two dozen countries in the Caribbean, Central America and South America. Now, cases of Zika have been confirmed in the U.S. and Europe in people who have recently traveled to an outbreak area where the virus is spreading. Individuals can also become infected after direct contact with someone who has just returned from one of these areas. What makes public health officials in America highly concerned about this virus is that it is spread by mosquitoes called Aedes aegypti and Aedes albopictus that are common in the eastern and southeastern United States.

There is accumulating evidence that Zika infection in pregnant women leads to birth defects, most notably microcephaly. This means Zika could potentially threaten thousands of unborn fetuses. The images of the babies afflicted by this disorder, which causes abnormally small head sizes, are heartbreaking.

But the damage to babies born to a mother who was infected is not limited to this highly visible birth defect. There is emerging evidence that Zika can cause other neurological problems. In a recent study of 42 fetuses from women testing positive for Zika, 12 babies showed a range of neurological problems. Seven had lesions in the central nervous system, five had issues with brain development and an additional two were stillborn. The neurological lesions are devastating and lead to significant developmental issues. Mothers who become infected with Zika immediately become part of a high-risk pregnancy group. Evidence now suggests that Zika infection is associated with neurological disorders in children and adults as well.

Most adults who become infected with the Zika virus don't experience symptoms, and it's usually mild for those that do. They have symptoms such as joint pain, fatigue and low fever, which usually last two to seven days. Some adults however can develop Guillain-Barré syndrome, an autoimmune disorder. However, women who are pregnant or want to become pregnant in the near future should avoid Zika-infected areas, and men who've traveled to Zika-infected areas should refrain from unprotected sex for at least two months since the virus can be transmitted sexually. Currently, there are not any treatments or vaccines for Zika, so hang on, we are in for a bumpy ride this summer and beyond.

Medical Discovery News is hosted by professors Norbert Herzog at Quinnipiac University, and David Niesel of the University of Texas Medical Branch. Learn more at