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Astigmatism is the most common vision problem. It may accompany nearsightedness or farsightedness. It is usually caused by an irregularly shaped cornea, but sometimes it is the result of an irregularly shaped lens. Either type can be corrected by eyeglasses, contact lenses, or refractive surgery.
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A seasonal flu vaccine is the best way to reduce the chances you will get seasonal influenza and spread it to others.
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Most childhood vaccines are 90–99% effective in preventing disease. Side effects are rarely serious.
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The first-known contraceptive was crocodile dung, used in Egypt in 2000 BC. Condoms were also reportedly used, made of animal bladders or intestines.
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Medication errors are three times higher among children and infants than with adults.