New Tick Disease In US Dogs Could Pose Future Risk To Humans, Experts Warn

A newly identified tick-borne disease in the United States has raised concerns among scientists after causing severe illness and death in several dogs. The infection comes from a previously unknown species of the Rickettsia genus, the same family of bacteria responsible for dangerous illnesses such as Rocky Mountain spotted fever (RMSF).

Researchers at North Carolina State University successfully isolated the bacterium from a sick dog showing symptoms similar to RMSF. Genetic sequencing confirmed it as a completely new species, now named Rickettsia finnyi, after Finny, the dog whose blood sample led to its discovery. The findings have been published in Emerging Infectious Diseases.

Scientists first reported this pathogen in 2020, and since then, they have found infections in 16 more dogs, mainly in the Southeast and Midwest. Symptoms ranged from fever and lethargy to severe drops in blood platelets. While most dogs recovered with antibiotics, three tragically died due to complications or late diagnosis.

Experts warn that many Rickettsia species can infect humans, and therefore any new species must be treated as potentially harmful. Early findings suggest that dogs may act as incidental carriers, and the bacterium appears capable of surviving long-term inside mammalian cells.

Researchers suspect the lone star tick may be the main vector, as DNA of R. finnyi has been detected in this species in Oklahoma. The tick's range also overlaps with areas where infected dogs were found.

Given the possibility of animal-to-human transmission, scientists stress the need for urgent surveillance to identify host species and understand potential public health risks.