ney ▁K ark . ▁In ▁ 1 9 5 5 , ▁Sus ser ▁and ▁Stein ▁left ▁South ▁Africa ▁for ▁political ▁reasons , ▁taking ▁positions ▁at ▁Manchester ▁University . ▁While ▁there ▁the ▁couple ▁published ▁a ▁paper ▁on ▁the ▁ep ide mi ology ▁of ▁pe ptic ▁ul cers ▁and ▁Sus ser ▁co author ed ▁an ▁early ▁text book ▁on ▁Medical ▁Soci ology , ▁among ▁other ▁contributions . ▁ ▁In ▁ 1 9 6 5 , ▁Sus ser ▁and ▁Stein ▁moved ▁to ▁Columbia ▁University ▁to ▁lead ▁the ▁Division ▁of ▁Ep ide mi ology . ▁Ide as ▁from ▁a ▁series ▁of ▁lect ures ▁given ▁at ▁Columbia ▁were ▁published ▁in ▁the ▁book ▁C aus al ▁Th inking ▁in ▁the ▁Health ▁Sciences . ▁At ▁Columbia , ▁Sus ser ▁founded ▁the ▁Ger tr ude ▁H . ▁Ser g iev sky ▁Center , ▁where ▁he ▁was ▁named ▁a ▁chair . ▁ ▁Tow ards ▁the ▁end ▁of ▁their ▁care ers , ▁Sus ser ▁and ▁Stein ▁became ▁increasing ly ▁concerned ▁about ▁the ▁H IV ▁ep ide mic ▁both ▁in ▁New ▁York ▁and ▁in ▁South ▁Africa . ▁They ▁helped ▁to ▁organ ise ▁a ▁conference ▁in ▁Map uto ▁in ▁April ▁ 1 9 9 0 , ▁which ▁aim ed ▁to ▁alert ▁the ▁African ▁National ▁Congress ▁about ▁the ▁H IV ▁ep ide mic ▁in ▁South ▁Africa , ▁sad ly ▁with ▁limited ▁effect . ▁Sus ser , ▁Stein ▁and ▁colle agues , ▁worked ▁on ▁building ▁scientific ▁capacity ▁in ▁Southern ▁Africa ▁to ▁deal ▁with ▁the ▁H IV ▁ep ide mic ▁and ▁Sus ser ▁and ▁Stein ▁served ▁as ▁early