The Zika epidemic has long assumed global proportions, experts told the Congress of the European Academy of Neurology in Copenhagen. Europe needs to get prepared to deal with the relentless spread of the health threat, in particular with a view to "imported" infection. Awareness for prevention and personal protection is important, in particular with thousands of athletes and fans soon travelling to the Olympics in Rio de Janeiro, a region particularly hit by the virus.
"Time is not on our side. The Zika virus is more and more not only showing its ugly face, but also its potential to go truly global", Prof Raad Shakir (London, UK), President of the World Federation of Neurology (WFN) told the Second Congress of the European Academy of Neurology which is taking place in Copenhagen, Denmark. The global Zika virus epidemic, its neurological angle and its implications for Europe are among the topical issues discussed at this major medical meeting. "We clearly see a relentless spread of the epidemic, and Europe will not be spared from this development."
Neurological expertise crucial to deal with Zika consequences
"Neurological expertise will be crucial to deal with the consequences of Zika", Prof Shakir stressed. "The WFN has recently established a working group in support of the efforts of international organisations, agencies and governments in response to the Zika crisis." One important task the group of high level experts is currently undertaking is the development of formal guidelines outlining diagnostic criteria for neurological complications of the Zika virus.
There are many misunderstandings and a lack of awareness about the actual risks involved in Zika virus infections, the WFN President said. "Many people still seem to believe that only pregnant women should be concerned because of the devastating foetal malformations when the infection is acquired during pregnancy, such as microcephaly. While this is, indeed, a particularly tragic consequence of the virus, we need to be aware that infected persons are also at risk of developing serious neurological conditions such as Guillain-Barré syndrome (GBS), myelitis or meningoencephalitis. But the full spectrum of neurological complications from this viral infection still remains unknown."
While the effects of Zika on the adult nervous system are still being studied and not fully understood, preliminary findings such as a recent study from Brazil published in the Lancet suggest that exposure to the virus increases the odds for GBS 60 fold. GBS leads to paralysis due to immunological effects of the virus. Morbidity and mortality are high. In the absence of supportive treatment, more than five percent of affected individuals will die.
Europe will not be spared
"Europe certainly needs to get prepared, just as other parts of the world, to cope with the consequences of the fact that the geographical distribution of the virus is steadily and rapidly expanding," said John England, Professor of neurology at Louisiana State University in New Orleans and chair of the WFN Zika Working Group. "The most recent WHO document places most of Europe in a low to moderate risk category mosquito transmission of Zika. The exceptions are where Aedes mosquitos are known to exist. I believe that in Europe, the concern should mainly be about people contracting Zika elsewhere and then returning to Europe.
We have already seen a number of person-to-person transmissions in Europe, inter alia in Germany and France. A case of possibly Zika-related microcephaly is under verification in Spain and a case of GBS associated with Zika virus infection has already been reported in a returning traveller to the Netherlands. The Rio Olympics are a special epidemiological risk since so many people are expected to go there. It would be unrealistic not to assume that we will see more imported cases after thousands of athletes and fans return from the Olympics in Rio de Janeiro, an area particularly hit by the virus."
In coping with Zika and its consequences, Europe has a clear advantage compared to other regions, Prof England said: "In this part of the world there is a relatively high amount of resources for neurological care available. This is not the case for many of the countries which are right now affected most by the virus and where we have witnessed unnecessary deaths which would not have happened in less deprived parts of the world."
With no specific effective treatment and no vaccination in prospect on the short run, although some vaccine candidates are being developed, awareness for prevention and personal protection needs to be created. Prof England: "All European countries should put measures in place in order to detect imported cases of Zika virus early and should provide public health advice to travellers to and from affected countries, including on sexual transmission."
In addition, in countries with a high likelihood of transmission strengthening vector-control activities to prevent the introduction and spread of mosquitoes, and reduce their density, particularly for areas with Aedes aegypti, is very important, the expert underlined.
According to recommendations which WHO and the Pan American Health Organisation PAHO have recently published, athletes and visitors to the Olympic and Paralympic Games in Brazil should, inter alia, protect themselves from mosquito bites by using insect repellents and wearing adequate clothing; practice safe sex or abstain from sex during their stay and four weeks after their return and choose air-conditioned accommodation. Pregnant women continue to be advised not to travel to areas with ongoing Zika virus transmission, and this includes Rio de Janeiro.
60 countries report Zika transmission
According to latest WHO figures, as of 18 May 2016, 60 countries and territories report continuing mosquito-born Zika transmission. Ten countries, among them Germany and France, have reported person-to-person transmission of Zika virus, most probably via a sexual route. Microcephaly and other fetal malformations potentially associated with Zika virus infection or suggestive of congenital infection have been reported in eight countries or territories. Thirteen countries and territories worldwide have reported an increased incidence of Guillain-Barré syndrome and/or laboratory confirmation of Zika virus infection among GBS cases.
European Academy of Neurology