Mosquito Borne Disease at the Paris Olympics: reducing the risk

With millions of fans and visitors, plus hundreds of athletes from across the globe expected to arrive in Paris this July, the French government and organizers are intensifying efforts to mitigate potential risks to public health – including the spread of infectious diseases.  

Typically, such a large sporting event might expect to see more cases of common illnesses like gastrointestinal infections and influenza – however, another potentially dangerous infection control challenge which has recently grown in prominence is the risk posed by mosquito-borne diseases.  

Transmitted to humans through the bite of a mosquito carrying a virus or parasite, mosquito-borne diseases include dengue, chikungunya, and zika. While the mosquito itself may not be affected, these diseases can cause immense suffering for humans, in some cases leading to long-term complications and even death.¹  

A growing global problem  

Normally, concerns about the risk of mosquitoes at mass public events are something we would more commonly expect to associate with tropical and subtropical regions. For example, organizers of the 2016 Summer Olympic Games in Rio conducted daily inspections of venues in the run up to the games to minimize the impacts of an outbreak of Zika in the region.  

However, the impacts of climate change over recent years, such as rising temperatures and increased rainfall, have expanded the territories of disease-carrying mosquitos. Currently, mosquito-borne diseases infect up to 1 in 10 people worldwide each year, however projections suggest that as many as 8.4 billion people could be at risk of contracting these diseases by the year 2100.² 

Additionally, whilst outbreaks of mosquito-borne disease have previously been confined to regions like sub-Saharan Africa, Latin America and South-East Asia, more cases are also now being reported in previously unaffected areas, such as the U.S. and Europe. 

Preparation and prevention 

Mass sporting events can create a unique environment and specific public health risks that must be managed accordingly. For Paris, organizers will also need to factor in the presence of competent vectors, such as the Asian tiger mosquito, which carries strains of serious diseases and is now widely established in France. Further to this, there may be athletes and spectators travelling from areas where mosquito-borne diseases are endemic.  

Positively, health authorities in Paris are taking measures to prevent the spread of mosquito-borne diseases, committing to make the event ‘mosquito free’. Approaches include enhancing surveillance, conducting fumigation, and exploring the use of innovative solutions such as mosquito traps that mimic the scent of the human body.  

Health protection measures should also include educating people travelling to Paris about the risks associated with mosquito and tick-borne diseases before their trip, along with encouraging them to undertake precautionary measures such as: 

• Using insect repellent   
• Covering up by wearing long sleeved tops and long trousers 
• Being wary of stagnant water sources, as these provide ideal conditions for mosquito breeding 
• Asking their GP about available vaccinations that can protect against mosquito-borne diseases  
• Familiarizing themselves with the symptoms of these diseases and establishing where to seek medical support if they begin to feel unwell 

Protecting public health 

In our post-pandemic world, we are now more aware than ever of the impact that infectious disease outbreaks can have not just on our enjoyment of public events, but on our wider healthcare infrastructures. Active collaboration between the scientific community, governments and vaccine manufacturers is vital if we are to both protect those attending mass events and combat the growing public health challenge of mosquito-borne diseases.  

At Valneva, our vision is to live in a world where no one dies or suffers from a vaccine preventable disease. Through strategic partnerships and pioneering vaccine research programs, we hope to make a significant difference to global public health efforts by limiting the threat of infectious diseases, including mosquito-borne diseases. 

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References
1 – World Mosquito Program. Mosquito-borne diseases webpage. Available at: https://www.worldmosquitoprogram.org/en/learn/mosquito-borne-diseases Last accessed May 2024.
2 – World Economic Forum (2023). As climate change boosts mosquito-borne diseases, we must take action to stop their spread. Available at: https://www.weforum.org/agenda/2023/01/health-risk-climate-change-demands-collective-action-davos23/ Last accessed May 2024.