Why could having bad case of acne not let you into the national guard?

i read it in this article first paragraph





http://news.yahoo.com/s/ap/20090902/ap_on_re_us/us_slimmer_national_guard|||Severe acne is a health hazard - each zit is an easily opened wound that is almost sure to become infected. If a soldier was constantly hindered because of infections, he%26#039;d not only be less effective than other soldiers, but in case of emergency would be a drain on medical supplies and manpower.