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Author Question: Which of the following has emerged as one of the most pressing challenges of the early 21st century? (Read 180 times) |
The average human gut is home to perhaps 500 to 1,000 different species of bacteria.
HIV testing reach is still limited. An estimated 40% of people with HIV (more than 14 million) remain undiagnosed and do not know their infection status.
Thyroid conditions cause a higher risk of fibromyalgia and chronic fatigue syndrome.
A cataract is a clouding of the eyes' natural lens. As we age, some clouding of the lens may occur. The first sign of a cataract is usually blurry vision. Although glasses and other visual aids may at first help a person with cataracts, surgery may become inevitable. Cataract surgery is very successful in restoring vision, and it is the most frequently performed surgery in the United States.
Before a vaccine is licensed in the USA, the Food and Drug Administration (FDA) reviews it for safety and effectiveness. The CDC then reviews all studies again, as well as the American Academy of Pediatrics and the American Academy of Family Physicians. Every lot of vaccine is tested before administration to the public, and the FDA regularly inspects vaccine manufacturers' facilities.