I could be wrong, but this might be a satirical reference to a statement from the Malaysian Minister of Health, stating that the heat from drinking hot water can kill the coronavirus.

Edit: rephrasing

Ririfu said:

I could be wrong, but this might be a satirical reference to a statement from the Malaysian Minister of Health, stating that drinking hot water can kill the coronavirus.

Well, staying hydrated is a good way to stay healthy and the healthier you are the better chance you have at fighting the virus if (god forbid) you catch it. But there's no "catch-all-cure" for dealing with the virus.

Man, it seems like that bullshit saying that you can cool off by drinking hot drinks instead of cold ones has somehow gone worldwide.

ilnarnar said:

Man, it seems like that bullshit saying that you can cool off by drinking hot drinks instead of cold ones has somehow gone worldwide.

That is at least partially true, since drinking hot things can make you sweat, which in turn will cool you off.

Though its better to do with extremely spicy food since it also makes you sweat but doesn't actually raise your temperature.

It's an old joke that much earlier than current coronavirus situations. Chinese netizens use this phrase to mocking some nerdy or thoughtless boys whom can't understand girls' thoughts, for example:
G: "I don't feel very well, I may cought a cold."
B: "Drink more hot water."
Or:
G: "I'm in my period, my stomach hurts."
B: "Drink more hot water."

Sounds like the old joke about the little old lady who tells everyone with a problem to eat chicken soup. When told chicken soup isn't going to help, she replies "couldn't hurt."