Others, like Holt City, had also recovered well after the fire plague. First of all, some of the formulas they already had. After all, Zenno was originally from their City and had used their resources to create several of the initial versions or prototypes of what were being used now.
They also had huge amounts of resources, so after they received the formulas, they had dozens of expert alchemists figure out the formula (which were presented as efficiently as possible, which impressed these alchemists).
After that, thousands of people were mobilized to make batches and batches of the inhibitors, the vaccines, and eventually, the cure.
Like this, next to Alterra, Holt City was the next to settle down the plague.
In fact, the average time was even faster if one considered the numbers, considering Holt City had millions of people within its walls, citizens or not.
