Which example represents vector-borne transmission?

Vector-borne transmission refers to the process where pathogens are transmitted to humans through a vector, which is typically an organism such as an insect or arachnid that carries the pathogen. In this case, the correct answer involves the West Nile virus, which is transmitted through the bite of infected mosquitoes. Mosquitoes act as vectors that carry the virus from birds (the primary hosts) and then transmit it to humans when they bite.

In this context, the other examples provided do not fit the definition of vector-borne transmission. Influenza is primarily spread through respiratory droplets when an infected person coughs or sneezes, which does not involve a vector. Malaria is transmitted through the bite of infected Anopheles mosquitoes, but the mention of contaminated water here indicates a different transmission method. Finally, Lyme disease is transmitted through the bite of infected ticks, rather than through contaminated food. Each of these examples illustrates a different mode of transmission than vector-borne, highlighting the specificity of this type of disease spread.