claim: Salt River Valley is south of the Phoenix metropolitan area.
evidence: Robert Wayne McCollum , Jr. -LRB- January 29 , 1925 -- September 13 , 2010 -RRB- was an American virologist and epidemiologist who made pioneering studies into the nature and spread of polio , hepatitis and mononucleosis while at the Yale School of Medicine , after which he served for nearly a decade as Dean of the Dartmouth Medical School .. American. United States. virologist. Virology. epidemiologist. Epidemiology. polio. polio. hepatitis. hepatitis. mononucleosis. mononucleosis. Yale School of Medicine. Yale School of Medicine. Dartmouth Medical School. Dartmouth Medical School