SciTech

The Zika Virus: A Harmless Harbinger

Credit: Maegha Singh/ Credit: Maegha Singh/ Credit: Claire Gianakas /SciTech Editor Credit: Claire Gianakas /SciTech Editor

If you have been paying attention to world news lately, chances are that you might have seen some headlines about the Zika virus. While the virus has been around for a while, recent surges in the virus’ prevalence have caused the disease to be pushed into the limelight.

Discovered in the 1940s, the virus has maintained a low profile until appearing in major outbreaks within the past decade. However, like an infectious disease, knowledge of the Zika virus is beginning to spread in greater proportions among the general public. According to the Centers for Disease Control and Prevention (CDC), the disease is typically transmitted when an infected mosquito bites a person.

For the most part, the Zika virus is not considered to be truly harmful. For every five people that are infected with the virus, approximately one person actually becomes ill and displays symptoms, which include fever, rash, joint pain, and red eyes. In fact, due to the lack of symptoms, most people who contract the virus will never know that they were infected.

Found in tropical and subtropical regions, the Aedes species of mosquito is the carrier of the Zika virus. After being infected by the virus, there is normally a 10 to 11 day incubation period, after this period, a mosquito becomes capable of transmitting the virus. Areas with stagnant water sources provide an environment in which mosquitoes can breed and pass the disease to their offspring, so these areas further increase the number of carriers for the Zika virus.

Besides mosquito bites, a few reports suggest that the virus could be spread through blood transfusions and even sexual intercourse.

In April 1947, researchers studying the development of jungle yellow fever in rhesus monkeys within the Zika Forest of Uganda first discovered the Zika virus after extracting it out of the monkeys’ blood. Mice and monkeys in the laboratory were also capable of becoming carriers of the virus, according to a report in 1956.

Between 1951 and 1981, evidence of the Zika virus was found in blood samples taken from native African and Asian individuals. The first outbreak of the Zika virus took place in the spring and summer of 2007, where it had infected 73 percent of 7000 inhabitants in the island state of Yap, a cluster of islands located north of Papua New Guinea. Despite the 73 percent infection rate, only a smaller fraction of the infected population actually presented with symptoms.

A few years ago, the Zika virus made its way to more islands, including French Polynesia, located west of Fiji. There some patients reported having symptoms of a rare autoimmune disorder called Guillain-Barré syndrome, which causes paralysis of the entire body. Questions about the virus continued to arise as the virus moved into South America.

According to the head of the World Health Organization (WHO) Margaret Chan, the mosquito-borne virus has “explosively” spread in 22 countries and territories in the Americas since it was first found in Brazil last May. There are new suspicions that Zika virus might be able to infect the fetus of a pregnant woman, an unusual trait that has not been found in other related viruses.

Doctors suspect that the disease may be correlated with the increase in cases of microcephaly in newborns in Brazil, where the number of reported cases have gone from around 150 cases per year to approximately 4000 cases each year. Microcephaly is a potentially life-threatening condition which causes babies to be born with smaller heads and underdeveloped brains, so this increase in incidence is cause for concern. However, more research is needed to make a conclusive statement.

After decades of maintaining a low profile, the Zika virus has finally entered the spotlight in the realm of global health concerns. The concern has grown to a point where the El Salvadorian government is advising women to postpone pregnancy until 2018. While the disease has not been actively transmitted in the U.S., a handful of individuals that returned to the U.S. from overseas have been diagnosed with the Zika virus. The CDC has issued guidelines recommending that women who have traveled to Zika-infected countries check in with their doctors.

The fact that the virus goes largely unnoticed further complicates the matter for pregnant women. A lack of reliable tests makes it hard for women to know if they have acquired the virus and if the virus has interfered with the early stages of pregnancy. Currently there is no cure for the Zika virus, and the current development of Zika vaccines could take years before entering completion. In the meantime, while in Zika-infected countries, travelers are advised to use mosquito nets and wear mosquito protective gear.

As the virus continues to spread to more people and more countries, officials from WHO will convene in early February to determine if the Zika virus disease should be declared as a global public health emergency. With the decision will come international guidelines that will coordinate a more effective response to the disease, including the possibility of sending aid to countries battling with these outbreaks.

Keeping the Zika virus under control requires a carefully planned and systematic approach. While the disease leads to devastating effects in childbirth, it is important to note that the disease is known to cause few symptoms in the general population.