What diseases entered the European population pool in the 2nd and 3rd centuries AD?

In the 2nd and 3rd centuries AD, several diseases began to affect the European population, notably smallpox and measles, which are believed to have been introduced through trade routes and military campaigns. Additionally, the Antonine Plague, likely caused by either smallpox or measles, swept through the Roman Empire, leading to significant mortality. These diseases marked a shift in the health landscape of Europe, contributing to population decline and impacting social structures.