In the early 20th century the American South was ravaged by pellagra, a nasty disease that produced the
“four Ds” — dermatitis, 16 , dementia and death. At first, pellagra’s nature was uncertain, but by 1915 Dr.
Joseph Goldberger, a Hungarian immigrant employed by the federal government, 17 conclusively shown
that it was caused by nutritional deficiencies associated with poverty, and especially with a corn-based diet.
However, for decades many Southern citizens and politicians refused to accept this diagnosis, declaring
either that the epidemic was a fiction created by Northerners to insult the South or 18 the nutritional
theory was an attack on Southern culture. And deaths from pellagra continued to climb. Sound familiar? We’ve known for months what it takes to bring Covid-19 under control. Most advanced
countries have gone down this route. A few countries, like New Zealand and South Korea, have largely or
completely defeated the coronavirus. But the United States is exceptional, in a very bad way. The rate of new
cases never declined all that much, because falling infection rates in the New York area were 19 by flat or
rising infections in the South and the West. Why? A lot of the answer is that many state governments have
rushed to return to business as usual even though only a handful of states 20 federal criteria for even the
initial phase of reopening. Epidemiologists warned that premature reopening would lead to a new wave of
infections — and they were right. 【題組】18. (A) that (B) to (C) by (D) X