FILE: A close-up view of a male brown dog tick (Rhipicephalus sanguineus) on a leaf.

Three people hospitalized in California died from Rocky Mountain spotted fever, a “severe” tickborne disease endemic to parts of the Americas, over a period of three months in 2023, a November report from the Centers for Disease Control and Prevention said. The patients — ages four and a half, 17 and 65 — all visited or lived in Tecate, a tourist destination in Northern Mexico, within eight days of the illness’ onset.

In total, six cases of RMSF were reported to the California Department of Public Health from July 2023 to January 2024, the report said. After interviewing surviving patients and family members, officials........

© SFGate