Airport and Aviation Services Chairman Major General G. A. Chandrasiri told Colombo Gazette that the infected woman was detected following random PCR tests conducted last evening.
The woman is part of the janitorial staff deployed by a private company to serve at the Katunayake airport.
He said the infected woman is a 43-year-old resident of Arachchikattuwa in Chilaw.
Health authorities have commenced contact tracing and medical procedures with regard to the infected woman.
Major General G. A. Chandrasiri further said the 10 janitorial staff who were placed in self-isolation will be subjected to PCR tests today.
A female staff member of the janitorial services at the BIA tested positive for COVID-19 in October as well.