Saudi Arabian child dies after COVID-19 test swab breaks in his nose

Why, if this virus is so contagious, is it necessary to test for it by jamming that long swab so far up your nose? Article link: https://english.alarabiya.net/en/coronavirus/2020/07/15/Coronavirus-Saudi-child-dies-due-to-a-COVID-19-test-swab-breaking-in-his-nose