Figure 3. Effects of Increased Health Care Worker Vaccination on Patient Attack Rates in Different Scenarios.

For all scenarios under study, the influenza virus attack rate among patient decreases in an approximately linear way when the health care worker vaccination rate is increased.

(A) The expected attack rates for the open and closed departments, where patients have many or no contacts with individuals from the community, respectively.

(B) The attack rates for seasons with high (15% community attack rate) and low (5% community attack rate) influenza virus activity.

(C) The attack rates for departments with high and low HCW/patient ratios.