Tick-borne relapsing fever (TBRF) is a disease caused by several species of spiral-shaped bacteria (spirochaetes) that are transmitted to humans through the bite of infected soft ticks.
Toisintokuume on punkkien levittämä tauti, jota aiheuttavat useat korkkiruuvimaiset bakteerit eli spirokeetat. Ihminen saa bakteeritartunnan punkin puremasta.