Day: August 14, 2025

Vaccines for West Nile Virus and Mosquito-Borne Diseases in Europe

Currently, no human vaccine exists for West Nile virus, while a vaccine for horses is available, with additional vaccines in development for birds, reports 24brussels.

Dengue and Chikungunya Risks

Dengue and chikungunya viruses are not endemic to Europe, appearing only during the summer months. These diseases are transmitted by the Aedes albopictus or Asian tiger mosquito, an invasive species in Europe, with host animals not participating in the transmission cycle.

Dengue can induce flu-like symptoms, including fever, headache, nausea, and joint and muscle pain. In severe instances, it may lead to bleeding from the gums, abdominal pain, and potentially, death. The risk of severe dengue, which can become hemorrhagic, increases for individuals who have been infected multiple times. This disease poses a significant danger to older adults, pregnant women, and children, though mortality rates in Europe remain low, with no reported dengue fatalities in 2024.

Chikungunya symptoms closely resemble those of dengue, featuring high fever, headache, nausea, rash, as well as muscle and joint pain. The term chikungunya originates from the Kimakonde language of southern Tanzania, translating to “that which bends up,” reflecting the severe joint pain that often causes patients to hunch over. While most individuals recover, 30 to 40 percent may develop chronic arthritis, making it particularly hazardous for older adults, pregnant women, and children.

The majority of dengue and chikungunya cases reported in Europe are imported, occurring among travelers returning from regions where outbreaks persist, thereby posing a risk for local transmission.

In 2025, significant outbreaks have been noted in several Indian Ocean islands, including the French territories of La Réunion and Mayotte, along with Mauritius. The viral spread has also been observed in Madagascar, Somalia, and Kenya.