Ticks can transmit pathogens, including the bacteria that cause Lyme disease, when they bite humans. But how do ticks become infected? Mice and other small rodents can function both as hosts for ticks and as reservoirs for zoonotic pathogens. Wageningen University & Research researchers study the immunology, physiology, and ecology of these rodents, which involves trapping rodents in forests, examining them for ectoparasites, and collecting blood and tissue samples. This leads to better understanding of disease dynamics in wild animals and the threats posed to humans.