Zika Virus infection is caused by the Zika Virus (ZIKV) belonging to the Flaviviridae family. The virus is primarily transmitted by infected daytime biting female Aedes aegypti and Aedes albopictus mosquitoes which are typically active from dawn to dusk. There is evidence that Zika Virus is also transmitted by other mosquitoes belonging to the Aedes genus.
Zika Virus is present in Mexico, Central America, South America, the Caribbean, tropical areas of Southeast Asia, Oceania, and parts of Africa. All travellers are at risk. Long-term travellers and aid or missionary workers going to areas where Zika Virus is endemic are at greater risk.
Information about the virus is continuously evolving. However, there is strong scientific consensus that Zika Virus causes neurological complications: Guillain-Barré syndrome (progressive muscle weakness that can lead to temporary paralysis) and microcephaly (decreased head size which may lead to developmental delays) in infants born to pregnant women infected with the virus.
The virus can be also sexually transmitted. In some patients, researchers have found that the virus can be shed through saliva and urine.
In the majority of cases, Zika Virus infection is asymptomatic – persons do not exhibit symptoms. Those with symptoms usually get ill 3-12 days after being bitten by an infected mosquito. Symptoms include mild fever, headache, muscle and joint pain, nausea, vomiting, and general malaise. The illness is characterized by pink eye (inflammation of the conjunctiva), a skin rash with red spots on the face, neck, trunk, and upper arms which can spread to the palms or soles, and sensitivity to light. Some may also have a lack of appetite, diarrhea, abdominal pain, constipation, and dizziness. Most people fully recover from the illness within 7 days. Treatment includes supportive care of symptoms. There is no antiviral treatment available.
Travellers who are pregnant or planning to get pregnant should postpone travel to areas with Zika Virus outbreaks. Other travellers planning to travel to areas with Zika Virus should take meticulous measures to prevent mosquito bites during the daytime. There is currently no preventive medication or vaccine against Zika Virus.
To reduce the risk of sexual transmission, practice safe sex – use a condom correctly and consistently or abstain from sex. Both men and women who plan to visit, are returning from, or have recently lived in a country where Zika Virus is active, should practice safe sex for 6 months.
Health risk description last reviewed: September 15, 2016
Country information last updated: April 17, 2017