A 52-year-old male presents with blisters on his skin and a fever. What condition is this most consistent with?

The presence of blisters on the skin accompanied by a fever in a 52-year-old male is most consistent with smallpox. Smallpox is a highly contagious viral infection characterized by its distinct rash that evolves into fluid-filled blisters, often accompanied by systemic symptoms such as fever, malaise, and aches.

The blisters in smallpox appear after an individual has experienced flu-like symptoms for a couple of days. These blisters develop in stages and can lead to significant scarring. Unlike chickenpox, which can also present with blisters and fever, smallpox lesions have a more uniform appearance and progression.

Shingles, caused by the reactivation of the varicella-zoster virus, typically affects only one side of the body and presents with a painful rash that follows a nerve distribution, along with fever in some cases, but it does not usually present with blisters all over the body like smallpox. Chemical burns would cause blisters as well, but the systemic manifestation of fever would not typically align with chemical burns as a primary condition.

Thus, the combination of widespread blisters and fever strongly aligns with the characteristics of smallpox.