Instead, the patient, who recently returned from a trip to west Africa, is being admitted to the special unit to avoid the risk of the disease spreading, says Britt Åkerlind, infectious disease control physician at the Linköping University Hospital says.
The patient has already received treatment at Gothenburg's Sahlgrenska hospital.
"It is serious, but Lassa fever is the least dangerous of the group of viral haemorrhagic fevers," says Åkerlind.
Regional authorities in Östergötland have said that the woman does not need intensive care for now.
Lassa fever is a contagious viral disease. Person-to-person infection is particularly common in the hospital environment in the absence of adequate infection control measures, according to the World Health Organization.
The Linköping University Hospital is Sweden's only health-care center with high-level isolation facilities. It can only treat two patients at a time. Last year, a patient suspected of having Ebola was admitted to the hospital.