The bugs became almost extinct across Norway around 70 years ago, but they have made a comeback and their numbers have exploded.
The species are known as Cimex lectularius and are a house insect that comes out in night time to suck blood. They do not spread diseases.
Worried residents should look out for a yellowish brown body that's flat and almost eggshaped. Adults grow to around 5 millimetres long.
Pest control expert Hans A. Sætrum has worked for Oslo Veggdyrkontroll since 1969. He said to NTB: “After World War II the bed bug was almost extinct. In the 1980s, there was no more than three or four cases of bed bugs in a whole year. Now it has exploded and we have three to four [cases] every day.”
The small animals prefer to attack when their victims are asleep where they emerge from cracks in bedroom walls and crawl inside your bed. The pests also attack larger animals and birds, including chickens, doves, mice, cats and dogs.
While you itch and scratch, the bugs breed many more. They tend to lay their tiny eggs in bed frames, behind picture frames and behind wallpaper cracks.
It is possible but complicated to get rid of the bugs. Bed bug expert Vidar Andreassen advises all infected furniture has to be frozen.
“We can put everything that's inside an apartment into freezing containers where the temperature is 28 degrees Celsius,” said Andreassen.
Freezing your furniture and sanitizing an average house can cost up to 50,000 kroner ($7,600).
Chemical treatment is also used to get rid of the bugs. The insects can withdraw into panels in the wall where pesticides cannot reach and where the adults can survive for months.
In order to avoid spending all that money on their eradication, Andreassen gives some advice:
“The most important is to not get them back in your luggage,” he said.