3 patients in Stockholm have been infected with what is known as LGV - a disease caused by a strain of chlamydia. The patients have experienced chronic pain and bleeding.
In Europe and the US, LGV has been found in males who have had sexual contact with other men.
The infection is being described as aggressive but can be treated with antibiotics.
Patients with LGV are more susceptible to HIV infection. And the majority of patients diagnosed with the disease also have HIV.