Credit ECDC
# 6452
In 2007 Chikungunya made headlines as it spread rapidly across the Indian Ocean, hitting Reunion Island particularly hard. A tropical disease - Chikungunya is spread by the bite of Aedes mosquitoes - and until recently was found only in Africa and parts of the Indian Ocean.
So the unexpected outbreak of Chikungunya in September of 2007 in Northern Italy took many by surprise.
I told the story in It's A Smaller World After All, but briefly: a traveler returning from India brought the virus back to the northeast Italian province of Ravenna, and before the outbreak had run its course, more than 290 people were infected.
This importation and subsequent spread of a rare tropical disease was a bit of a wake up call for Europe, and since then we’ve seen a good deal of study and concerns on the future of vector-borne diseases across Europe.
In 2010 the journal Eurosurveillance devoted an entire issue to The Threat Of Vector Borne Diseases, with perhaps the biggest threat outlined in Yellow fever and dengue: a threat to Europe? by P Reiter (excerpt below).
The history of dengue and yellow fever in Europe is evidence that conditions are already suitable for transmission. The establishment of Ae. albopictus has made this possible, and the possibility will increase as the species expands northwards, or if Ae. aegypti is re-established.
Last year in ECDC: Local Malaria Acquisition In Greece we saw more reasons for concern in the return of a scourge that had – due to diligent mosquito control measures over the past 50 years – been all but eliminated across Europe.
As global climate change occurs, and as mosquito species are spread inadvertently through the movement of trade goods, ships, and airplanes, the potential of new – potentially invasive – mosquito species setting up shop in Europe increases.
Which was the subject of an ECDC Review of status and public health importance of invasive mosquitoes in Europe last April.
While Malaria and Yellow Fever are of concern, the big worry has been the rapid global spread of Dengue fever over the past couple of decades might soon reach into Europe.
This explosive growth of Dengue around the world is well illustrated by the following graph from the World Health Organization.
What this graph doesn’t indicate is another doubling of dengue cases has taken place over the past 5 years.
All of which serves as prelude to a 27-page technical report published by the ECDC today on the potential of Dengue Fever getting a foothold in continental Europe.
Below you’ll find the summary, and a link to the report.
ECDC report: Low risk of dengue transmission in Europe, while some areas climatically suitable
26 Jul 2012
ECDC
Europe appears to be at little risk from dengue transmission in comparison with other global locations, even though climatic conditions exist in some parts, new ECDC report concludes.
The report, entitled‘Climatic suitability for dengue transmission in continental Europe‘, summarises the key findings of a project, which developed a series of risk maps demonstrating the current and potential distribution of dengue in continental Europe.
The maps explore the geographical distribution and the climate suitability of dengue and the dengue mosquito vectors - Aedes aegyptiand Aedes albopictus - in Europe to assess which areas could be most suitable for dengue transmission.
The current risk to Europe appears to be minimal, yet some areas are more climatically suitable than others. However, the report provides a relative but not absolute calculation of the risk of dengue transmission.
Much of central and Mediterranean Europe is climatically suitable for Aedes albopictus, states the report; the VBORNET maps on current known distribution of Aedes albopictus show that this mosquito species is already present in many places in Mediterranean Europe. In addition, some areas could potentially be a suitable habitat for Aedes aegypti (the Mediterranean areas of Spain, France and Italy, south-eastern Europe).
The climatic suitability maps can be used as a tool for public health planning. A sensible strategy is to continue to monitor the spread of dengue mosquito vectors in Europeand expand vector surveillance in areas climatically suitable for these vectors.
In 2012 ECDC will produce guidelines to assist the Member States to implement invasive mosquito vector surveillance and improve coverage and harmonisation of data collection within the EU.
Technical report ‘Climatic suitability for dengue transmission in continental Europe‘
While the current risk of Dengue spread in Europe is considered minimal, the executive summary’s conclusion cautions that:
Suitability maps can be a useful tool for public health planning, but there are many potential sources of error that need to be properly understood.
The current risk to Europe from the transmission of dengue appears to be minimal, yet some areas of Europe are more suitable for transmission than others.
A sensible strategy is to continue to monitor the spread of Ae. albopictus across Europe, to maintain vigilance for Ae. aegypti, and to consider expanding vector surveillance in areas particularly suitable for these vectors.
Additional research is needed to better understand the ecology of dengue in a European context, and to assess the possible impacts of climate change and other important drivers of dengue on the risk of dengue in Europe.
For additional background on a variety of vector-borne diseases in Europe, and around the world, you may wish to revisit these earlier blogs.
A Pathogen That Still Plagues Mankind
tick . . . tick . . . tick . . .
Tracking West Nile Virus In Europe
