In previous posts [x] [x], I’ve laid out the rules that explain what
affects a nations’ health. This post, however, will elaborate in more detail to
show the different ways in which they can be affected and why that is.

For one thing, we know that the personification’s health is
predicated on their economic and political situation. That is, if they are
suffering from political issues (either domestic or international) or are
experiencing an economic recession, they will fall ill.

That said, let’s go through the symptoms they can experience. 

They can get colds or fevers: 

Ex: Several nations develop fevers or colds in reaction to
the Great Depression.

Ex: Austria will develop a high fever and eventually collapse if
Germany acquires a cold [from an economic slump].

“A reliable country that likes to approach things with a sober seriousness.
He approves of and supports lots of Germany’s ideas so he may look like one of the helper countries, but in reality the level of his dependency is pretty high.

So high that when Germany catches a little cold, Austria goes straight to high fever and eventually collapses, and so he doesn’t have much of a choice than to take good care of himself.”

Ex: England develops a cold after the American Revolution.

They can suffer from fatigue and exhaustion:    

Ex: The aftermath of the Napoleonic Wars.

They can die:    

Ex: Spain nearly dies during an economic recession before
Romano starts helping him recover with imports.

They can cough up blood:

This symptom in particular is depicted more as a consequence
of war (which includes separate battles/attacks) or civil strife. You’ll often
see the most devastated nations coughing up blood in panels where Hima
introduces different sides of the conflict.

Ex: Prussia, Spain, and Italy during the Napoleonic Wars.

Ex: Prussia during the American Revolution.

Ex: China during WW2 after being betrayed by Japan.

Ex: The disunity in the Holy Roman empire causes Holy Rome
to fall ill and cough up blood. His political situation isn’t stable, which, in
turn, is reflected in his poor health.

Bonus case: 

The nations cough up blood and get sick during conflicts,
but are nonetheless able to heal from these wounds with time as their country’s
situation stabilizes.

But, what if a personification never healed emotionally from
a conflict and keep reliving it over and over again?

Wouldn’t that explain why England coughs up blood and falls
ill every year during the fourth of July? The event is still fresh in his mind,
and regardless if it’s over and done with, his body reacts as if it’s still
happening.