For those of you out there that get sick easily (you never know when ((they)) will try to make you sick)
You might want to try the wim hof breathing technique. It hyper oxygenates the blood and boosts the immune system like mad. It's a simple technique
If you can manage taking cold showers (yes, even in the cold winter) it helps with immunity too. Also boosts testosterone. This isn't bro science, it's real science. DDG Wim Hof