Of the 37 Norwegian gay men who were diagnosed with HIV last year, 27 became infected after sex in Asia.
Most men were about 50 years old when they were diagnosed.
The number of heterosexuals who become infected while living in Norway has remained relatively stable in recent years.
Both heterosexuals and gays are also grouped according to whether they were infected before they arrived in Norway or once they were living in Norway.
Fifty heterosexual men were infected while living in Norway, approximately the same as in 2015.
Eight out of ten said they were infected by a casual partner.“This indicates that the infection pressure among this group has decreased within Norway,” Øyvind Nilsen, senior adviser at NIPH, said in a statement.
Although almost half of the new HIV-positive cases among men who have sex with men have a migrant background, the number of annual new HIV cases in this group has declined in recent years, compared to the peak in 2009.
Heterosexual contact accounted for 120 of the new cases, and homosexual contact for 87 cases, or 40 per cent of the total.
At the same time, the number of reported heterosexual cases dropped by 18 compared with 2015.This increase occurred among men who had sex with men outside Norway, usually in Europe.Most were about 33 years old when they were diagnosed.Newly arrived asylum seekers and migrants affect annual fluctuations the most, along with the counties’ variable admissions policies.To a large degree, HIV infection in Norway occurs in specific risk environments with unprotected sex and many partners, according to NIPH.Just under 2000 of the 6000 people with HIV in Norway are women.