I: Certain infectious and parasitic diseases

A75-A79: Rickettsioses

Rickettsioses are a group of bacterial infections spread to humans through the bites of infected insects such as ticks, fleas, and lice. Caused by rickettsia bacteria, these diseases often present initially with symptoms like high fever, severe headache, and rash, which usually appears on the wrists or ankles before spreading. Other symptoms may include muscle pain, joint pain, chills, or confusion. These diseases can advance quickly, affecting different systems in the body such as the central nervous system, the respiratory system, or even the circulatory system where they can cause life-threatening conditions like heart or lung failure if not treated promptly. Early diagnosis and treatment with antibiotics can help manage the progression of rickettsioses and reduce the risk of severe complications.