The Zika virus is an emerging mosquito-borne virus that was first identified in Uganda in 1947 in rhesus monkeys. It was subsequently identified in humans in 1952 in Uganda and the United Republic of Tanzania. Outbreaks of the Zika virus disease have been recorded in Africa, the Americas, Asia and the Pacific.
According to the World Health Organization, the incubation period (the time from exposure to symptoms) of the Zika virus disease is not clear, but is likely to be a few days. The symptoms are similar to other arbovirus infections such as dengue, and include fever, skin rashes, conjunctivitis, muscle and joint pain, malaise, and headache. These symptoms are usually mild and last for 2-7 days.
The Zika virus is transmitted to people through the bite of an infected mosquito from the Aedes genus, mainly Aedes aegypti in tropical regions. This is the same mosquito that transmits dengue, chikungunya and yellow fever. However, sexual transmission of the Zika virus has been described in two cases, and the presence of the Zika virus in semen has been seen in one additional case.
With about 500,000 people expected to visit Brazil for the Olympics this summer, researchers are scrambling to figure how much of a risk the Games might pose in spreading the Zika virus around the world. Virus trackers in Brazil say that the strain raging in Brazil probably came from Polynesia, where an outbreak was rattling small islands around the Pacific. Infectious disease specialists are particularly focused on the potential for the virus to spread to the United States. As many as 200,000 Americans are expected to travel to Rio de Janeiro for the Olympics in August. When they return to the Northern Hemisphere and its summer heat, far more mosquitoes will be around to potentially transmit the virus in the United States.
Brazilian researchers say they believe that Zika, which has been linked to severe birth defects, came to their country during another major sports event — the 2014 World Cup — when hundreds of thousands of visitors flowed into Brazil. The similar nature of attendance in both the World Cup and Olympics is what is causing authorities such as the World Health Organization (WHO) to be concerned about the possible risks of the Rio Olympics.
As many as 1.5 million people are believed to have contracted the virus in Brazil since the 2014 World Cup, and the authorities are now investigating thousands of reported cases of babies being born recently with brain damage and abnormally small heads. Zika has spread to more than 20 nations and territories in the Western Hemisphere, according to the World Health Organization, illustrating how quickly the epidemic can expand even without a big international gathering.
Now athletes and fans alike are trying to determine whether it makes sense to travel to Rio. Alysia Montaño, an American runner who competed at the United States Track and Field Championships while eight months pregnant, said the Zika virus could affect her decision to bring her young daughter, who will turn 2 in August, to the Games.
“The greatest thing is that I will not be a pregnant woman at the Olympics,” said Montaño in an interview with the New York Times, who is hoping to compete in Rio. “Having my daughter there is really, really important to me, but I’ll need to consider if she’ll be a spectator at home or at the Games themselves.”
Overall, medical professionals feel confident that the Zika virus will not compromise the Olympics and will likely take measures to ensure so.