Ayurveda is a recognized medical practice in India. Many Ayurvedic practitioners claim that fasting is a remedy for infections. Some make vague reference to research on autophagy.
Here are some examples:
"... Patients down with common fever are almost always advised to fast for one day, so that the body toxins get washed out for good; this opens up a healthy passage for the bed-ridden to be treated from fever as soon as possible."
"When you are of the belief that you have been infected by amoebiasis or have an over growth of candidas stop consuming food and water until your prana starts flowing to pingala and your hunger is back in fiery shape."
These are just two examples. There are many such sites with millions of followers.
I'm not convinced about such claims. Research shows that "intermittent" fasting boosts autophagy which in turn improves immune system in general.
Autophagy is a catabolic process where a cell "eats itself" and recycles the intracellular constituents. This also happens when cell naturally dies. Intermittent starving is only one of the ways autophagy gets induced and studies only show that autophagy induced by intermittent starving boosts immune system. Moreover, research also shows that some cancer cells also induce autophagy and rely on that for survival. In such cases, inhibition of autophagy is a actually a good strategy.
References for this are provided in a related question: Does intermittent fasting improve immune function through autophagy?
However, I don't think any of these imply "recovery" when you are already infected. It's like saying, "Your heart becomes healthy when you run regularly. So, start running when you have an heart attack".
Is there evidence whether fasting is beneficial even when one is already infected?