Final answer:
Miliaria rubra, or heat rash, occurs due to blocked sweat ducts often during hot, humid conditions, and is not a contracted disease from animals or other humans.
Step-by-step explanation:
Miliaria rubra, commonly known as heat rash or pr*ckly heat, occurs when sweat ducts become blocked and inflamed. This is not something that is contracted from others or transmitted by vectors such as mosquitoes, sand flies, or ticks which are associated with various other diseases. Instead, it is due to sweat retention during periods of hot, humid weather or excessive sweating.
For instance, wearing tight or synthetic clothing that doesn't allow sweat to evaporate can lead to this condition. Additionally, infants are more prone to miliaria rubra because their sweat ducts are not fully developed. While it can be quite uncomfortable, this condition usually resolves on its own once the skin cools and drying occurs.