(Vax-Before-Travel News)
Since the beginning of 2025, the European Centre for Disease Prevention and Control (ECDC) has reported West Nile virus infections in eight countries: Bulgaria, France, Greece, Hungary, Italy, Romania, Serbia, and Spain.
Case numbers reported so far this year are slightly above the average for the past decade, says the ECDC.
However, these figures remain lower than those seen in 2024 and 2018 when West Nile virus (WNV) circulation was particularly intense, with 382 and 385 cases reported by this point in the year, respectively.
While the geographical distribution has been centered in northern Italy, the ECDC’s data is now indicating the southern coast of France has become an outbreak zone.
As of August 19, 2025, 13 human cases of vector-borne West Nile virus infection have been identified in six departments of mainland France.
The affected regions are PACA, Occitanie, Corsica, and, for the first time, Île-de-France.
As the summer holiday season ends in 2025, the hospitalisation rate has been notably high, with 100% of reported cases requiring hospitalization this year, compared to 93% over the past decade, according to the ECDC.
The case fatality rate so far this year stands at 7%, which is similar to the 11% observed in the previous decade.
Additionally, neurological manifestations have been reported in 56% of cases this year, compared to 66% in the past decade. Generally, cases with more severe symptoms are more likely to be diagnosed, leading to an expectation of a dominance of neurological cases.
As of August 21, 2025, the U.S. CDC’s Travel Health Advisory for France does not identify WNV as a risk.
Both the ECDC and other health agencies recommend avoiding mosquito bites as the best strategy to reduce this health risk, as there are currently no approved vaccines available.