Mosquito-borne ailments reminiscent of dengue, Zika, and chikungunya may unfold through the Olympics to international locations the place they don’t seem to be usually prevalent, warn world well being specialists, as authorities step up illness monitoring within the French capital.
Greater than 11 million guests are anticipated to descend on the French capital for the Olympic and Paralympic Video games, with round 1.5 million travelling from overseas, in response to newest projections from the Parisian vacationer workplace.
It comes amid an elevated danger of the tropical illness dengue in France within the face of an ideal storm of heat, damp climate mixed with rising numbers of tiger mosquitos pushed northwards by world warming.
Most individuals contaminated with dengue exhibit no signs and there’s a actual risk that some could also be bringing the illness with them – and others returning with it to their house international locations – in response to illness specialists.
Najmul Haider, a lecturer at Keele College, in the UK, advised SciDev.Internet: “Mass gatherings [like the Olympics] at all times carry some form of danger. If [travellers] are contaminated with dengue, it is extremely seemingly they may be a supply of an infection in France.”
Osman Dar, advisor doctor in world well being on the UK Well being Safety Company says ailments picked up on the occasion may unfold quickly in a rustic the place that illness will not be already established, rapidly overwhelming a healthcare system ill-equipped for an outbreak.
“The importation of ailments is especially problematic for a rustic the place that illness is absent, however the vector [disease-carrying agent] … is current,” Dar advised SciDev.Internet.
“That is very true within the world South, the place healthcare infrastructure and surveillance techniques should not as sturdy.”
In line with Dar, surveillance of disease-carrying vectors reminiscent of mosquitoes, together with monitoring of individuals exhibiting signs, is essential to make sure a speedy response to any potential outbreak.
“It’s necessary that guests and healthcare suppliers get the suitable well being communications, each at house and within the nation they go to, so everybody is aware of what to look out for,” he mentioned.
Nonetheless, John Tembo, a scientific coordinator for Herpez, a medical analysis organisation in Zambia, says it may be troublesome to make sure routine testing for ailments reminiscent of dengue the place it doesn’t generally happen, particularly in resource-constrained international locations. This might result in outbreaks going undetected, he cautioned.
“It’s particularly regarding if the illness has ambiguous signs that may be mistaken for different, extra widespread ones,” Tembo advised SciDev.Internet.
“It won’t be recognized till it’s already develop into a critical well being concern.”
Good storm
The geographical attain of mosquito-borne ailments reminiscent of dengue, Zika and chikungunya has quickly expanded resulting from globalisation and local weather change.
About half of the world’s inhabitants is susceptible to dengue, with an estimated 100 to 400 million infections occurring annually, says the WHO.
Thus far in 2024 there have been 5,000 deaths from dengue recorded in 80 international locations, primarily in Latin America and Southeast Asia, in response to the European Centre for Illness Prevention and Management.
Chikungunya has comparable signs to each Zika and dengue, inflicting extreme fever and joint ache, whereas the Zika virus may also trigger critical start defects if a pregnant girl is contaminated.
All three ailments are unfold by tiger mosquitoes, which are increasing into areas now unused to mosquito-borne ailments. First launched into Southern Europe within the Seventies, they’re now established throughout Western, Southern, and Japanese Europe.
Regardless of this speedy enlargement, many instances of dengue in Europe are imported. In France between January and Might 2024, well being authorities recorded 2,166 imported instances, primarily traced to abroad French departments reminiscent of Guadeloupe, Martinique and French Guiana, all of that are experiencing dengue epidemics.
Santé Publique France, the French nationwide well being company, has solely reported a single non-imported case of dengue in 2024. Nonetheless, the increasing mosquito inhabitants, escalating summer season temperatures and growing importation of dengue from endemic areas has raised fears that an ideal storm could also be about to hit.
With heavy downpours in the beginning of the video games and heat temperatures, situations in Paris are perfect for tiger mosquitoes, largely present in city areas and close to water sources.
Prevention methods
French authorities say they’ve put in place measures to stop and monitor for illness outbreaks. The Larger Paris regional well being company has arrange 526 mosquito egg-laying traps to test for tiger mosquitoes.
Official knowledge exhibits that each one departments in Paris are susceptible to tiger mosquito colonisation.
Efforts to scale back mosquito breeding grounds—which could embrace trapping the bugs and eradicating water sources the place they lay their eggs—are centered on “areas conducive to mosquito proliferation close to locations of enormous gatherings”, in response to the company.
To assist monitor instances of sickness, the Institut Pasteur, a biomedical analysis basis, mentioned it was working intently with public well being groups in Paris to extend capability for the detection of infectious ailments through the video games.
French authorities, together with the WHO and the European Centre for Illness Prevention and Management, have additionally revealed well being steering for these attending the occasion.
Giovanni Satta, a lecturer at College Faculty London, at present on sabbatical on the WHO, advised SciDev.Internet that “being ready is our greatest weapon on the subject of stopping outbreaks throughout huge occasions”.
