Hi there! I'm sorry, but we currently do not offer wallpaper versions of most of our works. This is only because a lot of people have been stealing our photos and making monetary profit(s) from them. So we tend to avoid uploading hi-res versions of our works on DeviantArt. I am very sorry and I hope you understand.
But once the first draft of our Plague project has gone public, we will share downloadable media content with everyone (which will include wallpapers, icons, digital stickers, etc).
If you have any other questions, please let us know