Outdoor transmission of Covid-19 accounts for 0.1 percent of the country's Covid-19 cases.
Figures in the Irish Times show 262 of the total number of infections in the state have been attributed to being spread outdoors.
However, the Health Protection Surveillence Centre says it cannot determine where transmission took place for definite.
From this month the HSE will carry out seven-day contact tracing as opposed to two-days in the hope to determine source of infection better.
