User blog comment:IamJakuhoRaikoben/Chapter 475: Dimaria Chronos Yesta, Review./@comment-5303512-20160302135223/@comment-7418318-20160302183912

When Wendy was introduced they said that they didn't know that anyone alive was able to use healing magic. And I considering how members of three guilds, including the intelligence expert Hibiki and Brain the leader of the Magical Research Bureo all agreed on this I consider it very reliable information. So yes we can pretty savely assume that Wendy and Chelia are indeed the only two living practitioners of healing magic in all of Fiore and likely even the entire continent.

What Porlyuscia and normal medics can do can't compare at all to what healing magic can do.

Medics, herbalists and even fully trained dorctors with a fully stocked hospital (something you'll not find in the battlefield camp) can only reduce the time wounds need to heal and can prevent people from dying, but the wounded will still be out of the battle for days, weeks or even crippled for life.

Magical healing can bring them back into fighting shape in minutes.

If you need proof of that just look at the aftermath of Naval Battle. Porly said that only due to Chelia and Wendy, Lucy's life was no longer in danger. There were professional medics, a fully stocked medical facility and Porlyuscia all together and still Porly said it was due to the two magical healers that Lucy was no longer in danger of dying. Meaning that without the two magical healers, Lucy might well have died and certainly wouldn't have been up and about by the time the Dragons invaded.