"They have a connection to each other and are unvaccinated. The first case was infected abroad", says infectious disease doctor Thomas Wahlberg in the press release.
"Contact tracing has started, which means that we are trying to map out contacts that may have been exposed to infection. Those who have been exposed to infection will be informed."
Vaccination against rubella is included in the regular childhood vaccination program and the disease, which can lead to serious fetal damage, is therefore very rare in Sweden.
According to the Public Health Agency's statistics, the last confirmed case was in 2014.
