Zika virus is a member of the flavivirus family and is transmitted by infected mosquitoes, probably mainly by mosquitoes of the Aedes species (known as the tiger mosquito, because of streaking on the body). The possibility of transmission of the virus through unprotected sex is also considered. But this remains to be confirmed.
Generally, the Zika virus disease is relatively benign and heals spontaneously. The typical symptoms of a Zika virus infection, resemble those of an influenza are fever, joint pains and rashes.
The Zika virus at a glance :
- Genre: Flavivirus
- Vector: Aedes mosquitoes (usually spicy in the morning, late afternoon and evening)
In some cases, however, the Zika virus can cause neurological complications (Guillain-Barré syndrome, which is also observed in some other infections) or congenital complications: in pregnant women, Zika virus can cause brain malformations in patients with fetus, and in particular microcephaly (head too small). Although this hypothesis has not yet been fully confirmed, pregnant women are advised to avoid traveling to countries at risk.
Photo of multiple Zika viruses under the electron microscope. A single Zika virus (see arrow) has a diameter of about 40 nanometers.
Where does the Zika virus come from?
The Zika virus was first identified in 1947 in rhesus monkeys in the Zika forest in Uganda. The first human cases of Zika fever appeared in the 1970s in several states in Africa, then in Asia.
The spread of Zika virus in the world
Since then, various outbreaks of Zika virus infections have been reported in Africa, Central and South America, Asia and the Pacific region in the past.
Here are the key dates of the major Zika virus outbreaks:
- 2007: Zika virus is detected in Micronesia.
- 2013-2014: cases of Zika virus are recorded in French Polynesia, then in other Pacific islands (New Caledonia, Cook Islands and Easter Island).
- May 2015: Zika virus arrives in South America: after the first cases detected in Brazil, the virus spreads, during the year, to other countries of the continent.
- November / December 2015: The first cases of Zika virus are detected in French Guiana and Martinique.
- January 2016: Martinique and Guyana go to the epidemic stage. About twenty countries in the Americas are affected by the virus. In Europe, a few cases have been identified.
The situation in France
On this day, are affected by the Zika virus the following French territories: Guyana, Guadeloupe and Saint-Martin. Also, in January 2016, the Minister of Health, Marisol Touraine recommended pregnant women (or having a pregnancy project) to postpone trips to Guyana or the West Indies.
And in metropolitan France?
According to the High Council of Public Health: "The conditions for an autochthonous transmission of the Zika virus in metropolis are met, in the departments where the vector mosquito is present. The mosquito Aedes albopictus - the tiger mosquito, ndlr -y is implanted since 2004 (20 departments in red vigilance) and extends there (21 departments in orange vigilance). These departments are located in the south-east and south-west of France.
Countries affected by Zika in the last 9 months (as of 31 January 2016, source: ECDC):
Barbados, Bolivia, Brazil, Cape Verde, Colombia, Curacao, Dominican Republic, Ecuador, El Salvador, Fiji, French Guinea, Guadeloupe, Guatemala, Guyana, Haiti, Honduras, Maldives, Martinique, Mexico, New Caledonia, Nicaragua, Panama, Paraguay, Puerto Rico, Saint Martin, Samoa, Solomon Islands, Suriname, Thailand, Venezuela, Virgin Islands (USA).
For more information: www.paho.org
Authors: Dorothee Gebele, Dr. Nicolas Evrard