How Long After Infection Omicron Symptoms Start To Show Up

How fast the omicron variant spreads among people, including fully vaccinated young adults.

How fast the omicron variant spreads among people, including fully vaccinated young adults.

Omicron is highly transmissible and is the most dominant COVID-19 strain at this time due to how quickly it can spread.

For most cases, it takes 3 days from exposure to the Omicron variant to see the symptoms.

Also, in some individuals the symptoms can show up on the first day of infection or up to 8 days afterwards.

The findings come from a Norwegian study that looked at an Omicron outbreak following a Christmas dinner party.

The collected information was based on 111 participants who had attended that party which was held in Oslo on 26 November 2021.

Attendees were between the age of 30 and 50 and fully vaccinated or had previously had COVID.

They had also tested negative after taking a PCR test or rapid antigen test 1 to 3 days before the party.

However, there were no requirements for vaccination or COVID restriction rules for employees working at the restaurant.

Also, two days before the party, one of the attendees came back from South Africa where the Omicron strain was first detected.

Moreover, participants mingled, drank, and danced with the public at the venue before and after dinner.

In short, the initial data show a widespread transmission of the SARS-CoV-2 at the event.

Subsequently, after exposure, 74 percent of participants were diagnosed with the Omicron variant and requested to self-isolate at home for 10 days.

One case showed no sign of illness (asymptomatic) while 91 percent of participants reported at least three symptoms.

The common symptoms include:

  • cough in 83 percent of cases,
  • runny/stuffy nose (78 percent),
  • fatigue/lethargy (74 percent),
  • sore throat (72 percent),
  • headache (68 percent),
  • and fever (54 percent).

The severity of symptoms were scored from “1” meaning no symptoms to “5” meaning severe.

For most cases the severity level was reported “3” and none of the patients needed hospitalisation.

The authors concluded:

“The preliminary results of our outbreak investigation indicate that the SARS-CoV-2 Omicron VOC is highly transmissible among fully vaccinated young and middle-aged adults.

However, given the specific context of the outbreak in a high-risk setting for transmission, the findings must be interpreted with caution.”

The UK-based ZOE COVID study has added four more omicron symptoms to the above warning signs often seen in cases.

About the author

Mina Dean is a Nutritionist and Food Scientist. She holds a BSc in Human Nutrition and an MSc in Food Science.


The study was published in the journal Eurosurveillance (Brandal et al., 2021).


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