单选题 Although it is the elderly and the young infants who get the siekest from the flu, it is young children who are most susceptible. In community flu outbreaks, it is not unusual for 30 to 40 percent of children to get the infection, perhaps twice the rate of adult infection.
Flu spreads rapidly from child to child for a number of reasons. First, flu is spread by small respiratory droplets that are coughed or sneezed and float in the air. A well child can catch the flu from being in the same classroom or child care center with an ill child without them ever touching each other. (Contrast this with the way colds are usually spread, by large droplets on people's hands, making good hand washing an effective preventive strategy. )Also, flu appears to be contagious even the clay before symptoms begin, and because children don't get as sick as adults with the flu, they other stay in school or clay-care long enough to spread the disease to their classmates.
While few otherwise healthy children have any serious consequences from the flu, it is these children that are the major conduit by which flu spreads through the community and into households. In ordinary households, adults are more frequently infected by children than by other adults. And it is adults with chronic diseases, and the elderly—particularly grandparents—that suffer the major consequences of this virus. One author has aptly referred to children as the "Typhoid Mary's" of the flu.
Flu Vaccine is the best defense against the flu. It is recommended for all adults over the age of 65, or over the age of 50 if there are sufficient supplies, and for individuals of any age if they are at high risk. Those high risk individuals would include anyone with heart or lung disease, including asthma, and people with diabetes, chronic kidney disease or other chronic conditions.
But recognizing that it is children who spread flu to households, it can be strongly argued to offer flu vaccine to healthy children who are in regular contact with other fanfily members who are at high risk by virtue of their age or underlying illnesses. This will help keep flu out of these households. Even if the grandparent has had flu vaccine, immunizing the grandchildren makes sense because flu vaccine is more reliably protective in younger healthier individuals. In addition, there are about 8 million children in the U. S. who have underlying conditions—most notably asthma—that make them eligible for flu vaccine. Regrettably, three out of four of these children end up ever getting the flu vaccine.

单选题 According to the passage, why does the author say that flu is spread by children?

单选题 According to the author, what is the best way to defend flu against spreading?

单选题 Why does the author compare children to "Typhoid Mary's" of the flu?

单选题 This passage might be a part of______.

单选题 In this passage, the author holds a view that______.