Those who could afford the spices, which were schlepped great distances to markets, fared better.
Centuries ago especially in cities, people knew not to drink disgusting water. Low alcohol "small ale" was even drunk at breakfast. Mulling with spices gave further protection, either with cider, ale or wine.
7a) More on Turmeric; India & medical research:
As a side note, vitamin companies offer capsule extracts of the above spices as anti-inflammatories and immune-boosters. One can do that, assuming availablity. We can also steward health at home.