The Zika Virus: Everything You Need to Know

In February 2016, the World Health Organisation declared that the Zika virus outbreak was a Public Health Emergency of International Concern. Though first discovered in 1947, this was the first time the virus had caused such concern within the medical community. Afflicted areas included much of Central and South America, some of North America, as well as portions of Southeast Asia, particularly among The Pacific Islands.

In November 2016, the WHO relaxed their stance on the Zika virus, declaring it no longer a global emergency, with recognised rates of infection beginning to drop off. However, the Zika virus is still very much present in some areas of the world and a particular concern for the previously unexposed international traveller.

With that in mind, let us take a closer look at the Zika virus, how its transmitted, what are its symptoms, and where in the world it is still active.

What is the Zika Virus?

Zika virus is a member of the viral family Flaviviridae. It was first discovered in Uganda in 1947 among animals within the Zika Forest. The first recorded case in a human came in 1952, also in Uganda. Though originating in Africa, over the course of several decades the virus has spread across multiple different regions, particularly those with warm climates.

The virus is transmitted primarily through particular species of mosquito, who must feed on blood to lay their eggs. This however is just one method of transmission of the virus. In the history of the virus, there has been evidence of transmission though sexual intercourse (particularly between an infected male and a female). There have also been recorded cases of vertical transmission, otherwise known as mother-to-child transmission, where an infected pregnant mother passes the virus on to her unborn child, resulting in risks covered below. Though not a common occurrence, the Zika virus can also be passed from person to person through blood transfusions wherein the virus was not detected in a blood donor’s sample before transfusion.

What are the Symptoms of the Zika Virus?

In the majority of cases (approximately 60-80%) an infected individual will have minimal to no signs of infection, making it very difficult for virologists to track the progress of the virus. One can be asymptomatic for the duration of their infection and thus never be aware they were infected in the first place. This can make the virus easier to transmit as infected people will not take the necessary precautions to prevent them passing on the virus.

In stronger cases of the virus, symptoms have been described as a reasonably ‘light dose of influenza’, including but not limited to muscular aches and pains, sore and reddened eyes, swollen glands, and an itchy skin rash.

One risk associated with the Zika virus is of particular concern to pregnant women. There have been documented cases that suggest a strong possibility of vertical infection where the virus has been passed from mother to foetus. The most up-to-date research suggests that there is between a 5-11% chance of a foetus developing some sort of significant neurological abnormality such as Guillain Barré Syndrome or Microcephaly. [references below]

How do I Protect Myself from the Zika Virus?

There is currently no vaccine available to protect against the Zika virus, though there are some in various stages of clinical trial.

As obvious as it may sound, the avoidance of areas with recorded Zika cases is the primary way of protecting yourself from the virus. The main areas where the virus can pose a risk, as mentioned above, are South and Central America, the Equatorial regions of Africa, and the region encompassing the Pacific Islands. Typically if a region has cases of Dengue being reported then there is a good likelihood that Zika is also present.

However, if travel to any of these areas in unavoidable, there are other preventative measures you can take. Covering exposed skin and using a suitable mosquito repellent should reduce the risk of mosquito bites and thus reduce the risk of infection.

It is also advised to use some type of barrier protection when engaging in sexual intercourse when in afflicted regions to avoid the potential of sexual transmission of the disease from an asymptomatic partner.

For more information on best practice when it comes to the Zika Virus, you can visit the TMB website here.

Guillain Barré Syndrome

Zika and Microcephaly