In Espoo, nearly 100 people at the Nihtisilta reception centre have tested positive for the coronavirus.
About 410 asylum seekers are housed at the facility, which has been placed under quarantine.
As of Friday, all of the centre's staff and about half of the residents had been screened. Ninety-five residents had tested positive.
Some of those diagnosed with infections have already recovered. Most of those who tested positive have had mild or no symptoms.
The facility is run by the Luona company, which also operates a reception centre in Vantaa. Two cases have been confirmed there so far. No mass testing or quarantine is planned there for now.
Luona Business Director Suvi Salonen says that no-one from the Espoo site has required hospital treatment.
"Most of them have mild or no symptoms. Some have congestion, coughs, tiredness and slight fever," Salonen says.
None of them are members of risk groups, as these people had already been moved out to external housing.
No group dining
Residents of the reception centre are not allowed to leave the grounds, and have been told to stay in their rooms as much as possible. They can fetch meals on a staggered schedule to bring to their rooms or designated isolated spaces. Most of the residents live in one or two-person rooms, but some are in 3-6-person rooms.
Salonen says it is unclear how the virus arrived at the centre, and that the next steps will be decided on Monday in cooperation with Espoo health authorities.