Estimated incubation period for monkeypox cases confirmed in the Netherlands, May 2022

In May 2022, monkeypox outbreaks have been reported in countries not endemic for monkeypox. We estimated the monkeypox incubation period, using reported exposure and symptom-onset times for 18 cases detected and confirmed in the Netherlands up to 31 May 2022. Mean incubation period was 8.5 days (5th-95th percentiles: 4.2-17.3), underpinning the current recommendation to monitor or isolate/quarantine case contacts for 21 days. However, as the incubation period may differ between different transmission routes, further epidemiological investigations are needed.

Automated summary

Based on 18 confirmed monkeypox cases in the Netherlands, the average incubation period was found to be 8.5 days, supporting the recommendation to monitor or isolate/quarantine case contacts for 21 days. Further epidemiological investigations are needed to confirm potential differences in the incubation period between different transmission routes.