Just over 500 people in Sweden have been diagnosed with swine flu this winter and three have died, reported the Aftonbladet newspaper on Monday. Four people in Finland have died.
Authorities there are now urging everyone to be vaccinated, especially those in risk groups such as the heavily pregnant and the over-65s.
Epidemiologist Hélène Englund at the Public Health Agency of Sweden (Folkhälsomyndigheten) described the situation in Sweden as "the tip of the iceberg".
"Most people aren't tested, so we don't know how many people are affected. It's high time to get vaccinated, it's not too late," she told the paper.
Englund said that many Swedes are cautious of getting vaccinated due to the risk of developing narcolepsy, a condition that swept across Sweden as a result of the Pandemrix vaccine. But the epidemiologist explained that authorities had a new and safe vaccine.
"The vaccine that's being used is not the same as the one given during the pandemic. This one has no connection to narcolepsy."
Northern Sweden has been hit the hardest by the disease. Ten employees at the Sunderby hospital in Luleå were infected.