Definitions (K1, K2, etc.)

This page provides information about some definitions around COVID-19. Below you can find a table of content, which lists every definition we currently have on this page.

Contact Person

A contact person or i.e. a suspected infectee (German: Kontaktperson) is someone with contact to someone who is confirmed COVID-19 positive during the period of contagiousness (i.e. contagious contact).

Contagiousness usually exists from 48 hours before the onset of the disease (i.e. the onset of symptoms) to 10 days after the onset of the disease or, in asymptomatic cases, from 48 hours before to 10 days after specimen collection which resulted in a positive test result.

K1

K1 or Category 1-contact persons (in German “Kategorie I-Kontaktpersonen”) are contact persons with a very high-risk exposure.

Who is a K1 contact person?

  • Persons living in a shared household -persons with conversational contacts under 2 meters and longer than 15 minutes
  • People who have been in a closed room together with a positively tested person at a distance of less than 2 meters and 15 minutes or longer
  • People who were exposed to a relevant concentration of aerosols with a high probability regardless of distance (e.g. celebrating, singing together or doing sports indoors)
  • People with direct contact to secretions (e.g. coughing)
  • People with direct body contact (shaking hands)
  • Direct seat neighbors in the airplane or other long-distance means of transportation, like coach or train
Detailed definition K1
  • Persons who cumulatively had face-to-face contact with a confirmed COVID-19 case for 15 minutes or more in a distance ≤2 meters (especially household contacts)
  • Persons who have been in the same room (e.g. classroom, meeting room, rooms of a health facility) with a confirmed case at a distance ≤ 2 meters for 15 minutes or longer.
  • Persons with the following types of contact in an aircraft or other long-distance means of transport such as coach or train:
    • Passengers who were direct neighbors of the confirmed case, regardless of the travel time.
    • Crew members or other passengers, provided one of the other criteria applies upon indication of the confirmed case (e.g. longer conversation; or similar).
  • Persons who, regardless of distance, were likely to be exposed to a relevant concentration of aerosols (e.g. celebrating, singing together or playing sports indoors) or had unprotected, direct contact with infectious secretions of a confirmed case.
  • Persons who had direct physical contact (e.g. shaking hands) with a confirmed case.

What do I have to consider as a K1?

You should be quarantined until the 10th day after the last contact with the person tested positive.

  • If you have symptoms like a cough, fever or breathing difficulties or you notice any of the mentioned symptoms, call 1450. In this case you are considered a suspected case and should be tested for COVID-19.
    • If your test result is positive (confirmed case), quarantine begins anew from the onset of symptoms or the date your sample collection that led to the positive test result was taken.
    • If the test result is negative, the quarantine is still maintained until 10 days after the last contact with the person who tested positive. You could still fall ill during this time.

K2

K2 or Category 2-contact persons (in German “Kategorie II-Kontaktpersonen”) are contact persons with a low-risk exposure.

Who is a K2 contact person?

  • Persons who have had cumulative face-to-face contact with a confirmed case for less than 15 minutes at a distance of ≤2 meters
  • Persons who have been in the same room (e.g. classroom, meeting room, health care facility rooms) with a confirmed case at a distance >2 meters for 15 minutes or longer or at a distance of ≤ 2 meters for less than 15 minutes
  • Persons who have been on the same aircraft or other long distance means of transport such as coach or train as a confirmed case.

What do I have to consider as a K2?

  • Observe your state of health up to the 10th day after the last contact with the positive tested person, check your body temperature once a day (potentially write it down in a “diary”)
  • Reduce personal contacts to third parties and note the direct contacts/conversations you knowingly made
  • Keep your distance in personal contact and pay special attention to hygiene measures
  • If you experience coughing, fever or breathing difficulties or notice any of the mentioned symptoms, call 1450. A test will be arranged. In this case you are a suspected case and must stay at home.
    • If the test result is negative, the usual procedure in case of illness applies: stay at home until the symptoms subside.
    • If the test result is positive (confirmed case), the health authorities will order a 10-day home quarantine.

Suspected case

A suspectes case (German: Verdachtsfall) is any person, who meets the clinical criteria.

Confirmed case

A confirmed case (German: bestätigter Fall) is any person with direct laboratory diagnostic evidence of SARS-CoV-2, regardless of symptoms.