The number of screened passengers was obtained from airport records. The numbers of crew members on inbound international aircraft were estimated by using averages for fl ights into Auckland. The number of travelers detected at each step and referred to the next step of the screening process was obtained from Auckland Regional Public Health Service records. Virologic test results were extracted from laboratory information systems. A confi rmed case was one that met the current case defi nition (as published on the Ministry of Health website, www.health.govt.nz) and one for which RT-PCR result was positive.