Most people with an Omicron infection are contagious and feel sick for about a week, but mild symptoms can last a bit longer and some people develop longer‑lasting “long COVID” symptoms.

Typical Omicron timeline

  • Incubation (time from exposure to first symptoms): usually about 3–4 days, and up to roughly a week.
  • Acute illness (when you feel most sick): often around 3–7 days; many people start to feel better after about a week.
  • Virus in the body: one overview notes the virus generally clears in about 5–10 days after your first positive test, depending on how severe the infection is.

Example: Someone exposed on Monday might develop a sore throat by Thursday, feel their worst from Friday to Sunday, and start improving in the following few days, though a cough or fatigue could linger.

How long you’re contagious

  • Studies of Omicron show that over half of people can still shed live, infectious virus at day 7.
  • A smaller group (around 10–15%) can still shed live virus at day 10, and a small minority even at day 14.
  • Because of this, many health authorities moved toward at least 5 days of isolation from symptom onset or positive test, plus extra days of masking and precautions if symptoms persist.

In practice, many experts suggest acting as if you could still be infectious for around 10 days from when symptoms started, especially around high‑risk people.

How long symptoms can last

  • For many otherwise healthy, vaccinated people, symptoms such as sore throat, runny nose, and mild fever usually improve within about a week, though some may notice a lingering cough or tiredness beyond that.
  • Medical summaries note that Omicron symptoms can last days to a few weeks , depending on age, vaccination status, and underlying conditions.
  • A subset of people develop long COVID , where symptoms like fatigue, breathlessness, “brain fog,” or altered smell/taste can last for weeks to months after the acute infection.

Omicron on surfaces and skin (if you meant that)

If by “how long does Omicron last” you meant outside the body:

  • On plastic , lab data suggest Omicron can remain detectable for up to about 8 days (around 193 hours), longer than earlier variants.
  • On skin , Omicron lasted just over 21 hours in one study, again longer than older variants.

This doesn’t mean every contact leads to infection, but it’s part of why hand hygiene and surface cleaning still matter.

Quick recap (TL;DR)

  • Incubation: roughly 3–4 days after exposure.
  • Feeling most sick: about 3–7 days.
  • Virus usually gone from the body: about 5–10 days after the first positive test, though some shed infectious virus up to 10–14 days.
  • Mild symptoms sometimes linger for weeks, and long COVID symptoms can last months in some people.

If you or someone close to you has COVID‑like symptoms, worsening breathing, chest pain, confusion, or trouble staying hydrated, contact a healthcare professional or urgent care right away.

Information gathered from public forums or data available on the internet and portrayed here.