West Nile virus is a mosquito-borne flavivirus that is maintained in an enzootic cycle between mosquitoes and birds. Humans and horses are incidental dead-end hosts.
Sindbis virus is widely and continuously found in insects (the main vectors are Culex and Culiseta mosquitoes) and vertebrates in Eurasia, Africa, and Oceania. ECDC factsheet for health professionals
Crimean-Congo haemorrhagic fever is transmitted by bites from infected ticks (mainly of the Hyalomma genus) or by direct contact with blood or tissues of infected ticks.
Japanese encephalitis virus is present in Asia and Oceania, from Japan to India, Pakistan and Australia. Outbreaks are erratic and spatially and temporally limited phenomena, occurring quite unpredictably. The virus is a leading cause of viral encephalitis in Asia, with 30 000 to 50 000 cases reported annually.
Fleas are ectoparasitic blood-sucking insects with the ability to jump, which commonly infest wild and domestic animals (mainly dogs and cats) but also humans.
ECDC urges EU/EEA Member States to strengthen vaccination campaigns and prepare for the possible need to increase emergency department and ICU capacity, as well as to consider a number of public health measures to reduce the impact of respiratory pathogens circulating this winter, in latest epidemiological update.
Several viral and bacterial respiratory pathogens are expected to continue co-circulating at variable levels during the coming months, and contribute to increased morbidity and mortality during this period. This is typical of every winter season.
On 12-13 December 2023, ECDC organised a simulation exercise on the serious cross-border threat posed by the spread of antimicrobial resistance, in collaboration with WHO.