Swedish health authorities say they have identified the first domestic case of a patient with the same strain of E.coli bacteria that has killed 48 in Germany, even though the patient had not traveled there.

Health officials said Tuesday that the infected Swede also had no known connections with anyone who had taken ill after visiting Germany.

As a result, Swedish authorities said it might mean there is a new infected food product in circulation that they have yet to identify.

They said the patient fell ill in the middle of June, but now is reported to be feeling better.

There have been 53 previously reported cases of the E.coli infections in Sweden, all of them directly linked to the German outbreak.

German officials reported four more deaths Tuesday from the killer strain of E.coli bacteria, pushing the death toll to 48. The outbreak has most recently been blamed on organic vegetable sprouts grown in northern Germany.

The World Health Organization says the outbreak has sickened about 3,800 people in 16 countries, about 850 of them seriously.

European and French officials are looking into E. coli infections spread by sprout seeds after victims in France showed the same potentially deadly strain of bacteria as the German cases.

The European Food Safety Authority is setting up a task force to investigate the link between sprouted seeds and the potentially deadly E. coli infections.