| five years of sentinel surveillance of acute respiratory infections (1985-1990): the benefits of an influenza early warning system. | for the last five years, the brussels institute of hygiene and epidemiology has been involved in the surveillance of acute respiratory infections (ari). the four indicators used (number of encounters of ari by gp's/100 encounters, virus isolations, absenteeism and mortality) are discussed. a regression procedure is applied to the data collected by a sentinel network of general practitioners (gp's). this procedure permits the baseline to be visualized and an epidemic threshold to be determined in ... | 1992 | 1397213 |