The ID50 (the dose needed to infect 50% of experimental subjects) is one via inhalation; i.e., inhalation of one organism will yield disease in 50% of the population.
O ID50 (a dose necesaria para infectar o 50% dos suxeitos experimentais) é 1 vía inhalación; é dicir, a inhalación dun organismo producirá enfermidade no 50% da poboación estudada.