ABOVE: An adult female Asian longhorned tick (Haemaphysalis longicornis)
JAMES GATHANY, CDC
Many species of ticks need blood meals to grow, develop, and reproduce. During those blood meals, they can transmit diseases to their hosts. Researchers have known for several years that treating ticks with antibiotics to do away with bacteria that live inside them affects blood intake, but it wasn’t clear why. Now, a study published September 14 in Cell Host & Microbe shows that one such bacterial symbiont, Coxiella, influences blood feeding by the Asian longhorned tick (Haemaphysalis longicornis) by contributing to tick tryptophan metabolism, thus regulating serotonin production.
“That microbes . . . influence brain and behavior is really fascinating,” says Carlos Ribeiro, a neuroscientist at Champalimaud Centre for the Unknown in Portugal who did not participate in the study. “We are moving away from the phase where we are just documenting these effects [to] starting to understand ...
