According to the CDC, a person can be infected with a tickborne disease in as little as 10 minutes.
Brazilian ticks that carry Rocky Mountain spotted fever passed the disease to animal hosts in as little as 10 minutes if they had recently fed on another animal, a new study found.
“The current literature, including medical textbooks and guidelines for the general public, has repeatedly advised that an infected tick requires a minimum feeding period varying from 2 to 10 hours to transmit Rickettsia rickettsii – the bacterium that causes Rocky Mountain spotted fever – to humans,” study co-author Marcelo Labruna told Reuters Health in an email.
In the eastern United States, R. rickettsii is transmitted to humans typically by the D. variabilis tick in the adult stage, commonly known as the American dog tick, which feeds chiefly on domestic dogs.
Similarly to the circumstances in the São Paulo, Brazil, metropolitan area, most of the Rocky Mountain Spotted Fever cases in the eastern United States have occurred in children and women, and infections in dogs have been associated repeatedly with an increased risk for disease in owners.
Because numerous reports of infected humans were associated with tick-infested dogs or tick removal within 4 weeks of disease onset, researchers have proposed that many of these cases were a result of direct contact with rickettsiae from tick body fluids during tick removal.
The current literature has considered that an attached tick needs several to many hours of attachment for a successful inoculation of RMSF into human skin. Once it is forcibly removed from a host, a partially fed tick loses its discriminatory senses and strives to feed wherever possible on any available vertebrate animal.
Thus, it is reasonable to consider that tick removal habits in RMSF-endemic areas could have implications for the transmission of R. rickettsii, not only caused by potential direct contact with tick fluids, but also, as shown in this study, because detached ticks could readily attach to humans and inoculate them with rickettsiae within a few minutes.
Read more at Reuters Health.