Those Google counts are essentially meaningless.

@@ -13 +12,0 @@
-<gloss>school infirmary teacher</gloss>
@@ -16,0 +16 @@
+<gloss>school infirmary teacher</gloss>

https://ja.wikipedia.org/wiki/養護教諭
保健室の先生（ほけんしつのせんせい）などと通称されることが多い。 

google web hits:
"養護教諭": About 3,900,000 results
"保健室の先生": About 3,050,000 results

Google N-gram Corpus Counts
╭─ーーーーーー─┬─────────┬───────╮
│ 養護教諭　　 │ 112,052 │ 82.6% │ - daijr/s, koj, smk, gg5
│ 保健室の先生 │  23,608 │ 17.4% │
╰─ーーーーーー─┴─────────┴───────╯

Seems very common at least, but maybe not enough to make an exception for

@@ -10,0 +11 @@
+<pos>&exp;</pos>

This is more commonly used than 養護教諭 so it makes sense to add it as a definition.