It is almost impossible to determine who will be effected, although the elderly, asthma sufferers, smokers, and other individuals with respiratory disorders, such as COPD, Emphysema, etc. are at risk. Anyone of any age regardless of physical condition can be affected by altitude sickness, especially those visiting from sea level. Estimations from interviews with ER doctors and clinics conclude that over half to 60% of all vacationers that visit high altitude are at risk. High Altitude Sickness or Acute Mountain Sickness can be mild to severe. The only cure for altitude sickness is to acclimatize or descend, since it is better acclimatize, the use of supplemental oxygen is the cleanest, quickest and most economical way to acclimatize.