Is There a Medic in the Zone?

I thought it would be easier to compile all the information onto the main part of the achievement. So I went through some of the comments related and here's what I've gotten as of right now.

The links above are linking to the actual quest, so I'm going to link to the item itself and try to provide some additional info. Some of these drop from several mobs, and some drop from more specific mobs. Visit the item link to see where to find the monster that drops the one you need. :)

To complete these quests you need your First Aid skill at Legion level. Certain items will require certain skill level to use. For example you will learn Treat Fever early on in your Legion First Aid, however, Set Bone requires 800 skill. Silkweave Splint requires 760 skill.

Field Packs that you will need to complete these quests, have to be purchased from the First Aid vendor in (new) Dalaran.

Azsuna

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• Singed Note: Drops from Hatecoil Slavemaster (49,58) in Azsuna. You will need 3 Silvery Salves & 1 Field Pack.
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• Bloody Note: Drops from 3 mobs (click link for names and locations) in Azsuna. Path to NPC begins at 38.8,33.5. You will need 3 Silkweave Bandages & 1 Field Pack
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• Fevered Plea: Drops from many monsters (click link to see what and where) in Azsuna. You will need 3 Field Packs.
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Stormheim

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• Singed Letter: Drops from Fjorlag, the Grave's Chill (68,52) in Stormheim. You will need 3 Silvery Salves & 1 Field Pack
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• Crumpled Request: Drops in Stormheim. You will need 2 Silkweave Splints & 1 Field Pack.
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• Fevered Request: Drops from many monsters (click link to see what and where) in Stormheim. You will need 3 Field Packs.
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Suramar

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• Fevered Prayer: Drops from many monsters (click link to see what and where) in Suramar. You will need 15 Field Packs.
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• Bloody Letter: Drops from Misthollow Hunter (39,37) in Suramar. You will need 3 Silkweave Bandages & 1 Field Pack.
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• Singed Plea: Drops from Volatile Leywraith (23,17) in Suramar. You will need 9 Silvery Salves & 3 Field Packs.
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• Bloody Prayer: Drops from Lowland Hardshell (40,37) in Suramar. You will need 3 Silkweave Bandages & 1 Field Pack.
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Val'sharah

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• Bloody Plea: Drops from many monsters (click link to see what and where) in Val'sharah. You will need 3 Silkweave Bandages & 1 Field Pack.
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• Fevered Note: Drops from many monsters (click link to see what and where) in Val'sharah. You will need 3 Field Packs.
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• Bloody Request: Drops from two monsters (click link to see what and where) in Val'sharah. Entrance to barrow is at 49.96,85.42. You will need 3 Silkweave Bandages & 1 Field Pack.
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Highmountain

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• Fevered Letter: Drops from many monsters (click link to see what and where) in Highmountain. Path to the soldier starts at 45,35. You will need 3 Field Packs.
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• Crumpled Note: Worgen/Undead at Warden's Tower in Highmountain. You will need 10 Silkweave Splints & 5 Field Packs.
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• Crumpled Letter: Drops from mobs in PVP areas in highmountain. You will need 2 Silkweave Splints & 1 Field Pack
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*Currently, there is a bug to where if you collect one of these quests, and for whatever reason happen to leave the zone, it will show the soldier's location in Dalaran, this is incorrect. If you go back to the origin zone for the quest, it should display properly again.

Big thanks to everyone who has posted information on all those pages. As of this posting (9/8/16) the above information is believed to be true and accurate. I will try to remember to come back and update this post as we learn more!

Prior to 7.1 quests that have been completed were not tracking in the achievement. GMs have claimed that when they can implement a fix, that any past work on this achievement will be retroactively added. As of November 1. this has not happened yet, however, any quest you complete after the 7.1 launched should properly track on your achievement.

Also, I don't know if this is a bug due to the tracking being messed up, or if this is intended, but you can currently complete the same quest several times. I have rescued the guy from Fevered Plea at least 3 times.

Is this working?
I thought I'd done at least a couple of these but nothing is showing.

Check this comment for an updated guide for this achievement.