After recording 1,968 adverse reactions including 358 serious events, Japan's health ministry suspended HPV vaccine recommendations in June 2013. Reported adverse events included POTS, chronic fatigue syndrome, and complex regional pain syndrome. Denmark saw similar declines. Merck's clinical trials used aluminum adjuvant (AAHS) as the 'placebo' control rather than saline, potentially masking neurological adverse events. Over 63,000 adverse event reports and 438 deaths have been filed with VAERS.