People who have tested positive in England are being handed down a warning about retesting after recovering from Covid 19.
The news comes in the fallout of an unprecedented number of cases following the huge surge of the Omicron wave of the virus.
The advice is particularly aimed at workplaces in the hope of helping manage staff shortages.
The advice states that people who have recently had Covid should not take a PCR test after having had the virus within a certain timeframe.
This is because people who have recently had the virus could still test positive for some time after they had it.
The government says this is because some parts of the virus can remain in the body for long periods of time.
They say: "Fragments of inactive virus can be persistently detected by PCR in respiratory tract samples following infection, and for some time after a person has completed their isolation period and is no longer infectious."
How long do you need to wait to take a PCR test?
People who have had covid are being advised not to take a PCR test for 90 days, or around three months after they had covid unless they meet certain conditions.
Failure to listen to this advice could mean you have to isolate again despite not being infectious because it is the legal duty of anyone who tests positive to stay at home.
The aim of the new advice is to prevent the ongoing shortfalls in workforces in an attempt to help the country recover from the virus.
Documentation from the Department of Health & Social Care says: "Following a substantial clinical review of the latest evidence and testing data, we are now changing the advice for retesting within 90 days of a positive. From now on, if someone tests positive with a PCR test, they should not be tested using PCR or LFD for 90 days."
What conditions mean you DO need to take a PCR after having Covid?
People who develop new symptoms in the 90 day period will need to take a test once again.
The Department of Health & Social Care says that tests should be taken by those who have recovered inside the three month period if they develop symptoms, "in which case they should be retested immediately using PCR."
The documentation continues: "This 90 day period is from the initial onset of symptoms or, if asymptomatic when tested, their positive test result."
The reasoning for the change is explained by the Department: "The previous policy to continue LFD testing following a positive PCR result was because although very unlikely, it is possible to be reinfected within 90 days. However based on the latest testing data and clinical advice, the policy has now changed.
"The clinical view is that during this 90 day window from a positive test, given the low rate of reinfection during this window, it is significantly more likely that a positive LFD test would be a false result, rather than someone being re-infected, causing people to isolate unnecessarily."
The NHS also add that people may need to get a PCR within the 90 day period if they are required to take one after arriving in the UK from abroad.
