How long can you test positive for Covid and when are you contagious?

For more than two years, the Covid-19 pandemic brought the world to a standstill while the virus spread across the globe.

While lockdowns and tiers may seem like a distant memory now, the virus is still with us.

Cases have picked up again, with warnings Covid will put renewed pressure on the NHS this winter.

The latest major spike in the pandemic while restrictions were still in place came courtesy of Omicron. The variant quickly spread around the world after being spotted in southern Africa last November, and has since spawned a number of subvariants.

Omicron proved less severe but more transmissible than its predecessors, the Alpha and Delta variants, with total daily case counts in England soaring to a then-pandemic high of 218,724 on January 4, before gradually falling apart from a resurgence that was inspired by their first sub-variant, BA.2, in March.

Since then, second booster shots have only been offered to those over 75, meaning immunity could wane and calls for a new booster to be more widely available.

The approval of Moderna’s new Omicron-specific vaccine is a welcome development for the UK in this regard, and the vaccine could ultimately play a significant role in any further vaccination campaigns to come.

Different types, different effects

What public health officials had to learn in a snap when this variant first hit the market last winter was how it differed from the original Covid strain.

While the World Health Organization estimated that people infected with the first strain of coronavirus took between two days and two weeks to show symptoms, Omicron incubated much faster, closer to three to five days.

“Recent analysis by the UK Health Security Agency suggests that the window between infection and infectivity may be shorter for the Omicron variant than for the Delta variant,” then-British Health Secretary Sajid Javid told the House of Commons on December 6, 2021 .

This explained why the strain was able to spread so quickly and successfully, as the shortness of its incubation period allowed those affected a shorter window of time between suspecting they had contracted the virus and experiencing a flare-up, resulting in fewer positive lateral flow test results probably made in time to warn others to isolate and prevent transmission of the contagion.

A shorter incubation period “makes a virus much, much, much harder to control,” observed Jennifer Nuzzo, an epidemiologist at the Johns Hopkins Center for Health Security, in The Atlantic in the same month.

Another feature of Omicron that made it potentially harder to spot than previous strains was that its symptoms differed somewhat from the three main indicators we were conditioned to look for in 2020: cough, fever, and loss of taste or smell.

Symptoms to look out for

Early warning signs for the newer variant, on the other hand, included a sore throat, lower back pain, runny or stuffy nose, headache, muscle pain and fatigue, sneezing and night sweats.

Omicron cases analyzed in the UK found that patients recovered within five days to a week on average, although some symptoms, such as a cough and fatigue, were likely to last longer.

The shortness of breath experienced by some sufferers often lasted up to 13 days after other symptoms had passed.

Covid patients are typically considered contagious to others about two days before their first symptoms appear and about 10 days after.

If you think you have symptoms related to the coronavirus, the current advice from the NHS is to have a lateral flow test and isolate at home for five days if you test positive to prevent transmission to others avoid (you should stay away from people who are likely to be at high risk due to their age or a pre-existing condition for 10 days).

If you must go out in public, you should wear a face mask, avoid crowded indoor spaces, and wash your hands for at least 20 seconds.

If you are concerned about your symptoms or think they are getting worse you should visit 111.nhs.uk, call 111 or call your GP.