Tularemia increases reported in Sweden and Norway
Tularemia increases reported in Sweden and Norway
At least two countries in Scandinavia—Sweden and Norway—are reporting increases in the very infectious and potentially very serious bacterial infection, tularemia this year to date.
According to the Swedish Public Health Agency, or Folkhälsomyndigheten, 344 people from 15 regions have been reported infected with tularemia (harpest) through mid-September, which is significantly more compared to the average value for the period 2000-2022.
Most disease cases have been reported from Västerbotten (128 cases), Gävleborg (68 cases), Dalarna (34 cases) and Norrbotten (20 cases). Of the disease cases, 60% are men, the average age is 55 years and the age range is 3-91 years.
In all of 2022, Sweden 276 human cases of tularemia were reported.
Sweden has reported cases of tularemia in humans and animals since 1931. Ever since the first Swedish tularemia case was reported, endemic areas have been identified in northern and central Sweden.
In Norway, the Norwegian Institute of Public Health (FHI) has also reported an increase in tularemia.
There have so far been reported 54 people infected with hare plague in August and September reported to FHI's reporting system MSIS, with a total of 70 cases so far in 2023. Most of the cases have been reported from Viken, Oslo, Trøndelag and Innlandet. There are more cases than have been seen in the same period in the previous three years.
Tularemia, also known as rabbit fever and deer fly fever, is caused by the bacterium Francisella tularensis. This bacterium is found in nature in rabbits, rodents, beavers, squirrels and several domestic and farm animals.
The bacterium is highly infectious and can be transmitted to humans through arthropod bites, direct contact with infected animal tissue, inhalation of contaminated aerosols, and ingestion of contaminated food or water.
After infection with F. tularensis, incubation can be a couple of days to weeks, with non-specific symptoms like fever, chills, headache, sore throat and diarrhea.
The way the organism enters the body frequently dictates the disease and degree of systemic involvement. Th
e six syndromes are ulceroglandular, glandular, oculoglandular, oropharyngeal, typhoidal and the one with the highest mortality rate, pneumonic tularemia.
It is classified as a Tier 1 select agent because of its bioterrorism potential.