A lot has been said about the role of lateral flows tests as Wales reopens after lockdown.
These fast tests involve people swabbing their nose and throat, adding the swab to a solution and then putting that solution into a small white device that gives them a positive or negative reading, a bit like a pregnancy test.
In Wales, you can get lateral flow tests for you and your household if you volunteer or cannot work from home.
Also, if you attend or work at a school, college or nursery you can obtain rapid tests through your school, college or nursery and you're advised to do a test twice a week.
Wider Covid-19 community testing is currently available in certain areas and everyone who lives in these areas can get regular rapid COVID-19 tests.
You can get this if you live in:
However, you need to be careful when using these rapid tests because there is some doubt over how reliable they are, especially when they are not administered by professionals.
Let's look at the data in Wales to see how many Covid cases they are finding.
According to the last seven days of recorded data published by Public Health Wales, a total of 124,600 lateral flow testing episodes were carried out. Of these, just 79 were positive. That is just 0.06%. One reason positive results are so rare is that Covid is now very repressed and lateral flow tests mainly target people without symptoms so you would expect the success to be lower.
However it may be because they are not being carried out correctly.
Sian Taylor-Phillips, professor of population health at the University of Warwick, told Sky News: "We don't know how well lateral flow tests work in terms of accuracy in people's homes.
"So when people are doing the test unsupervised we don't know if it will still be as effective.
"We know that swabbing technique is really important but we don't know how well people can do that in their own homes.
"The really critical thing we don't know is what effect it has on the transmission of coronavirus."
It is therefore vital that you both carry out the test to the instructions but also do not assume you are not transmitting the virus even after a negative result. You must still follow the rules as you could still possibly spread the virus despite your negative result.
You can read full analysis of issue here.
