[BlessedBeGod]

Another article said he had 'stomach illness'. But which one?

If I remember correctly, it was gastroenteritis.

[Raycpa]

If I remember correctly, it was gastroenteritis.

Which can be caused by too much drinking.

[uncitizen]

According to the CDC website:

Gastroenteritis means inflammation of the stomach and small and large intestines. Viral gastroenteritis is an infection caused by a variety of viruses that results in vomiting or diarrhea. It is often called the "stomach flu," although it is not caused by the influenza viruses.

...viral gastroenteritis is contagious.

...Viral gastroenteritis outbreaks can occur in institutional settings, such as schools, child care facilities, and nursing homes, and can occur in other group settings, such as banquet halls, cruise ships, dormitories, and campgrounds.

With a contagious disease, he probably shouldn't have been going to Congressional meetings.