During her dozen years as a mental health counselor, Christine Hammond’s patients have visited her with a litany of troubling psychological symptoms: severe depression, anxiety, paranoia, delusions, hallucinations and even brief psychotic episodes.
But for some of these patients, the cause of their seemingly textbook mental issues isn’t from an anomaly of brain chemistry or function, but from Lyme disease – the most common vector-borne disease in the U.S.
The Centers for Disease Control and Prevention records about 30,000 cases of Lyme disease annually. Although the true number of infections – commonly caused by the Borrelia burgdorferi bacteria – may affect upwards of 475,000 people each year.
This number is far more than diseases like West Nile Virus, Dengue fever, and malaria, all which blood-feeding arthropods like mosquitoes, ticks and fleas spread. Lyme is acquired through the bite of blacklegged ticks – also called deer ticks – which carry the infecting bacteria.