The new variant was first discovered in Finland, where 160 cases were detected in the spring. So far, three people have been infected in Sweden - two in Örebro county and one in Västernorrland.
The characteristic of the new variant is that it is more difficult to detect than normal chlamydia.
- Some of these tests haven't detected it. Otherwise, it behaves like a regular chlamydia, says Hans Boman, infection control physician in the Region Västernorrland, to Sundsvall's newspaper.
The laboratory at Sundsvall Hospital, where the third case was discovered, has now changed its test methodology to also be able to detect the new variant.
According to Hans Boman, there is no reason to change the advice to the public or test patients again.