diff --git a/inc/class-filters.php b/inc/class-filters.php
index <HASH>..<HASH> 100644
--- a/inc/class-filters.php
+++ b/inc/class-filters.php
@@ -81,6 +81,9 @@ class CareLib_Filters {
 		// Default excerpt more.
 		add_filter( 'excerpt_more', array( $this, 'excerpt_more' ), 5 );
 
+		// Add an itemprop of "image" to WordPress attachment images.
+		add_filter( 'wp_get_attachment_image_attributes', array( $this, 'attachment_image_itemprop' ) );
+
 		// Modifies the arguments and output of wp_link_pages().
 		add_filter( 'wp_link_pages_args', array( $this, 'link_pages_args' ), 5 );
 		add_filter( 'wp_link_pages_link', array( $this, 'link_pages_link' ), 5 );
@@ -114,6 +117,18 @@ class CareLib_Filters {
 	}
 
 	/**
+	 * Add an image itemprop to attachment images.
+	 *
+	 * @since  0.2.0
+	 * @param  array $attr Existing attributes.
+	 * @return array Amended attributes.
+	 */
+	public function attachment_image_itemprop( $attr ) {
+		$attr['itemprop'] = 'image';
+		return $attr;
+	}
+
+	/**
 	 * Wraps the output of `wp_link_pages()` with `<p class="page-links">` if
 	 * it's simply wrapped in a `<p>` tag.
 	 *
Filter attachment image to include an image item prop

This could maybe go in attributes.php but since it’s filtering a
default WP function it probably should go here… I think?