External ventricular drains (EVDs) historically have a high rate of infection, and EVD infections are a cause of significant morbidity and mortality. We have shown previously that a simple infection control protocol reduced the rate of EVD infections during a 3-year period, and the present study examines whether infection rates were durably reduced over an additional 4 years. Retrospective analysis of EVDs placed in the intensive care unit of a tertiary neurosurgical center over an additional 4 year follow-up period. In the 4-year follow-up period, 189 EVDs were placed in 173 patients. The previously observed decrease in cerebrospinal fluid culture positivity from 9.8% in the baseline period to 0.8% in the first 3 years of the protocol period continued in the 4-year follow-up period (0%, 0 of 189 EVD placements, 0 per 1000 catheter-days; P < 0.001 compared with baseline). The previously observed decrease in the rate of ventriculitis from 6.3% to 0.8% also continued in the follow-up period (0%, 0 of 189 EVD placements, 0 per 1000 catheter-days; P < 0.001 compared with baseline). Over the total 7 years of protocol use, the rate of culture positivity was 0.3% (1 of 308 EVD placements, 0.29 per 1000 catheter-days) and the rate of ventriculitis was 0.3% (1 of 308 EVD placements, 0.29 per 1000 catheter-days). The only observed infection over 7 years occurred in a patient who removed their own EVD. A straightforward EVD infection control protocol substantially and durably reduces EVD infections to a near-zero rate.