Study finds excruciating tropical disease expanding its reach across Europe

Europe is in the grip of an excruciatingly painful tropical disease: chikungunya can now be transmitted by mosquitoes across the continent. A new study has discovered that the primary drivers behind this spread are the higher temperatures caused by the climate crisis. This means infections are now occurring for more than six months of the year in Spain, Greece and other southern European countries.

The study examined how temperatures affect the incubation period of the virus within the Asian tiger mosquito, a species that has severely impacted Europe in recent times.

In this connection, Sandeep Tegar, at the UK Centre for Ecology and Hydrology (UKCEH) said: “The rate of global warming in Europe is approximately double the rate of global warming at global scale and the lower temperatures limit for virus spread matters a lot, our new estimates are quite shocking.”

According to Dr Diana Rojas Alvarez, who leads the World Health Organization’s team on viruses transmitted by insect and tick bites said: “This study is important because it indicates that transmission in Europe might become even more evident over time.”

The study published in the Journal of Royal Society Interface used data from 49 earlier studies on chikungunya virus in tiger mosquitoes to determine the incubation time across the wide range of temperatures for the first time.

Chain of Infection: How easily can the virus spread to others?

When a mosquito bites an infected person, the chikungunya virus enters its gut, then after an incubation period, the virus is present in the mosquito’s saliva meaning it can infect the next person it bites. If that incubation period is longer than the lifespan of the mosquito then the virus is not transmitted.

It has been observed that outbreaks in Europe are sparked by infected travellers returning from tropical regions and being bitten by local tiger mosquitoes, which then spread the disease as reported by The Guardian.

At present, Europe’s cold winters have stopped tiger mosquito activity and act as a firebreak for the disease from one year to the next. Scientists are involved in seeing tiger mosquito activity all year in southern Europe, meaning chikungunya outbreaks are strengthening as the continent warms.

It is crucial to maintain continued vigilance to prevent the tiger mosquito from becoming established in the UK. This highly invasive species is capable of transmitting several infections that can cause serious health conditions including chikungunya, dengue and Zika viruses.