passages: 3503
passages: document
passages: Protection of man from natural infection with influenza A2 Hong Kong virus by amantadine : a controlled field trial . Prophylactic administration of amantadine in doses of 100 mg. twice a day offered statistically significant protection against influenza A2 infection in a double-blind field trial involving 391 medical student volunteers during the influenza A2 Hong Kong epidemic in Helsinki in the winter of 1969 . Serologically verified influenza , as measured by complement fixation and/or haemagglutination inhibition , occurred in 27 out of 192 students in the amantadine group against 57 out of 199 in the placebo group , giving a protection rate of 52 % .
entities: 3504
entities: Intervention_Pharmacological
entities: amantadine
entities: 3505
entities: Intervention_Pharmacological
entities: amantadine
entities: 3506
entities: Intervention_Pharmacological
entities: amantadine
entities: 3507
entities: Intervention_Control
entities: placebo
entities: 3508
entities: Outcome_Physical
entities: Serologically verified influenza
entities: 3509
entities: Outcome_Physical
entities: complement fixation and/or haemagglutination inhibition
entities: 3510
entities: Participant_Sample-size
entities: 391
entities: 3511
entities: Participant_Condition
entities: medical student volunteers during the influenza A2 Hong Kong epidemic in Helsinki in the winter of 1969