Can anyone tell me why it is that if you have or have had multiple sex partners you are more likely to catch hep c. I understand that it is mainly contracted from contaminated blood but you can however catch it sexually. But my question is why if you have had multiple sex partners?

But my question is why if you have had multiple sex partners?

The answer is rather simple actually. If you have had multiple sex partners your risk of being with someone who was infected with Hep C increases.

If you have been with multiple partners and none of them have Hep C, then you can't get Hep C. You must be infected by a person who has the virus.