Animal vectors of disease

Animals as transmitters of disease

Background

The global significance of animal vectors in disease transmission emerged in the late 19th century, following discoveries linking mosquitoes to malaria and yellow fever. Subsequent outbreaks of vector-borne diseases, such as the 20th-century spread of Chagas disease and Lyme disease, underscored the pervasive impact of animal vectors. Increasing international travel, urbanization, and climate change have since heightened awareness of their role in facilitating the rapid, transboundary spread of infectious diseases.

Incidence

Animal vectors of disease continue to pose a significant global health threat, with billions of people at risk from illnesses transmitted by insects, rodents, and other animals. Mosquitoes alone are responsible for the spread of malaria, dengue, Zika, and yellow fever, causing hundreds of millions of infections and over a million deaths annually. The incidence of vector-borne diseases is rising due to factors such as climate change, urbanization, and increased human-animal contact, affecting both developed and developing regions.
In 2022, an outbreak of Japanese encephalitis in eastern Australia highlighted the ongoing risk of vector-borne diseases. The virus, transmitted by mosquitoes, resulted in dozens of confirmed human cases and several fatalities, prompting widespread public health interventions and renewed surveillance efforts in affected areas.