Hygiene measures were intensified when the COVID-19 pandemic began. Patient contacts were limited to a minimum. Visitors were either not allowed for a certain period or limited for the rest of the time. The hospital staff began to wear masks and gloves continuously. Clinical examinations and routine wound controls were also performed under intensified hygiene standards. These circumstances result in a limitation of direct physical interactions between the nursing staff, the physicians and the patients. We analyzed to what extent the intensification of hygiene measures affects the rate of surgical site infections (SSI) after neurosurgical procedures. The rate of SSI during the 6-month interval after the beginning of COVID-19 measures was compared with the SSI rate before. The numbers of the period before COVID-19 were analyzed as mean values resulting from the analysis of two separate time periods each consisting of 6 months. The spectrum of surgical procedures was compared. Patient-related risk factors for SSIs were noted. Microorganisms were analyzed. We focused on SSIs occurring at a maximum of 60 days after the primary surgery. Overall, in the two respective 6-month periods before COVID-19, a mean of 1379 patients was surgically treated in our institution. After the beginning of COVID-19 (starting from 04/2020) our surgical numbers dropped by 101, resulting in a total number of 1278 patients being operated after 03/2020 until 09/2020. The SSI rate was 3.6% (03/2019–09/2019, 50 SSIs) and 2.2% (09/2019–03/2020, 29 SSIs), resulting in a mean of 2.9% before COVID-19 began. After the beginning of COVID-19 hygiene measures, this rate dropped to 1.4% (16 SSIs) resembling a significant reduction (p=0.003). Risk factors for the development of SSI were present in 81.3% of all patients. Pre- and post-COVID-19 patient groups had similar baseline characteristics. The same holds true when comparing the percentage of cranial and spinal procedures pre- and post-COVID-19 (p=0.91). Comparing the numbers (p=0.28) and the species (p=0.85) of microorganisms (MO) causing SSI, we found a similar distribution. Despite equal demographics and characteristics of SSI, the rate of SSI dropped substantially. This argues for an effective reduction of postoperative SSI resulting from the implementation of strict hygiene measures being established after the beginning of the COVID-19 pandemic. We therefore advocate continuing with strict and intensive hygiene measures in the future.