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  • Definitions


Here are the definitions of suspected, probable and confirmed cases of COVID-19, of vaccination with primary vaccination series and risk groups.

Here are the definitions of suspected, probable and confirmed cases of COVID-19, of vaccination with primary vaccination series and risk groups.

Suspected COVID-19

A person who meets the clinical criteria: acute respiratory tract infection and one or more of the following symptoms; fever, cough, shortness of breath, loss of sense of smell/taste, or who is considered by a doctor to have suspected COVID-19.

Confirmed COVID-19

A person with coronavirus (SARS-CoV-2) confirmed by RT-PCR test, other nucleic acid amplification test or rapid antigen test (rapid immunoassay). See requirements for rapid antigen tests.

Close contacts 

You are considered to be a "close contact" if 

  • you have been in contact with a person with confirmed COVID-19 disease less than 48 hours before onset of their first symptoms. (From time of testing if the person does not develop symptoms) 
  • the contact has been
    • less than two metres away for more than 15 minutes OR
    • in direct physical contact OR
    • in direct contact with secretions.

This does not apply when recommended personal protective equipment is used in the healthcare service.

Household members and equivalent close contacts 

People are considered to be household members and equivalent close contacts if they: 

  • Live in the same household.
  • Have had similar close physical contact as in a household (for example, boyfriend/girlfriend).

Vaccinated with primary vaccination series:

  • Those who have received a second dose of vaccine. Status applies from 1 week after the second vaccine dose.
  • Those who have had the disease and at least 3 weeks later have received a dose of vaccine. Status applies from 1 week after the vaccine dose.
  • Those who have received the first dose of vaccine and then, at least 3 weeks later, have been diagnosed with COVID-19 infection. Status applies from one week after COVID-19 infection.
  • Those who have been vaccinated with a single dose vaccine, effective from 3 weeks following vaccination.
  • Those who have confirmed antibodies to SARS-CoV-2 by an approved laboratory method (with an antibody serology in a microbiological laboratory), and received one vaccine dose. The vaccine dose may be given the same day at the earliest. Status is valid 1 week following vaccination. 

Risk group refers to:

  • People aged 65 years or older
  • People with certain defined diseases / conditions that increase the risk of severe disease course and death from COVID-19 (medical risk groups).

Read more here:


14.02.2022: Updated definition of vaccinated according to regulation changes 12.2.2022

20.12.2021: Clarification of what «household members / similar close» and «other close contacts» means, and that they are subgroups of «close contacts»

23.11.2021: Removed definition of probable case because that is no longer used.

05.10.2021: Change to the list of approved vaccines, adding CoronaVac and Covishield.

27.09.2021: New definition of "partially vaccinated"

24.09.2021: Updated as per Norwegian version - household members

29.08.2021: Updated according to extended exemption from quarantine after being defined as close contact, for those who have recovered from covid-19 within the last 12 months.

23.06.2021: Clarification that other nucleic acid amplification tests (NAT) are considered equivalent to PCR tests (also specified in the covid-19 regulations).

19.06.2021: Removed ", colleagues who sit near each other in an open plan office" from the most exposed close contacts.

09.06.2021: Added definitions of fully vaccinated and protected and risk groups

07.06.2021: Added information about exemptions from infection quarantine for those who are protected (fully vaccinated and those who have received one vaccine dose)

19.01.2021: Added sentence "If the person who is confirmed to have COVID-19 does not develop symptoms, contact tracing is done from the time of testing." 

22.12.2020: Added sentence about confirmed methods being PCR and rapid antigen tests

11.11.2020: Updated definition of probable case

30.10.2020: The paragraph "probable COVID-19" is updated according to new definitions in the regulations

28.10.2020: Time indications for the contagious period for asymptomatic people , as well as assessments of what increases infectivity, have been moved to the chapter on contact tracing.

21.10.2020: The Chapter "Close contacts": Updated the sentence "Before the test" to "From the time of the test"

25.09.2020: updated definition of close contacts

27.08.2020: Changes to these sentences under "Probable COVID-19"

The category is used when it is not possible to carry out testing, or if the test result is delayed and the probability of infection is high. A probable case should be handled in the same way as a confirmed case. Household members and equivalent close contacts should be in quarantine, but it is not necessary for contact tracing of other close contacts

15.08.2020: From 13.08.2020, all close contacts shall be in quarantine, and there is no longer a distinction between the types of close contact.

13.08.2020 Added sentence that all close contacts shall be in quarantine, but that in some circumstances it can be useful to differentiate between "household members and equivalent close contacts" and other "close contacts". 

Minor change, added "examples include"

Added loss of sense of taste/smell as a symptom. Added examples of "household members or equivalent close contact." Some general text changes.

Definition of close contact changed from contact 24 hours before symptom debut until contact 48 hours before symptom debut.

Added 15 minutes continuously, as per Norwegian version.

General updates as per Norwegian version - added "probable" as a category


New article replaces the old version

Updated according to Norwegian text changes

Added "Low risk contact" to suspected cases. Updated definition of close contacts to mirror Norwegian text


Added two points in list under "definition of suspected case". Added changes to confirmed case definition.


Some definitions are updated according to changes in the Norwegian text


Updated according to Norwegian text changes (close contacts, direct contact)


Updated according to Norwegian text changes. Changed SARS-CoV-2 to COVID-19. "Other contacts" changed to "low risk contacts". Changed definition of close contact and added about closed spaces (e.g. classroom, meeting room, waiting room) with a confirmed cases, changed definition of physical contact to <2 metres for more than 15 minutes, changed from 2 seats rows on plane to in all directions, added people in same travel group as close contacts. Under low risk contacts added use of same transport medium.  

28.02.20 Updated according to Norwegian text - definition of a possible case

18.02.20: changed virus name to SARS-CoV2