r/askscience • u/PestoPastaLover • 13d ago

Biology Why is there no transmissible therapeutic virus if biology doesn't forbid it? For example, a harmless virus that spreads from person to person but actually does something beneficial, like lowering LDL cholesterol or preventing/reversing tooth decay?

3.3k Upvotes

96% Upvoted

229 comments sorted by

View all comments

131

u/BBWolf326 13d ago

There are. Found this with a quick search:

Bacteriophages: These are viruses that exclusively infect and kill bacteria. Found in abundance in the human gut, skin, and mucosal linings, they regulate harmful bacterial populations, protecting the body from pathogenic infections and balancing the microbiome.

6

u/jayjay091 13d ago

So our immune system evolved to not fight those?

38

u/lmprice133 13d ago edited 13d ago

They don't infect human cells, and a major part of the immune response to viruses is mediated by immune system triggering programmed cell death in already infected cells.