keen relic
https://github.com/LeGend077/diseases-addon
This add-on introduces a "realistic" experience by adding diseases and natural hazards to vanilla Minecraft.
Diseases can be caught almost anywhere, so be cautious as you explore your world. Even something as simple as prolonged exposure to sunlight can cause severe damage.
To experience this add-on, download both packs listed on GitHub and add them to your world. No experimental features are required.
This add-on is under MIT license.
Both made by:
@solemn wind and @keen relic
brisk fossil
solemn crow
stark jackal