Covid: How to get a test for coronavirus

Everyone in England will be offered two rapid coronavirus tests a week from Friday, whether or not they have symptoms, to help stop outbreaks as lockdown is lifted.

So, how do you get one?

You should arrange a free NHS test if you have any of the main symptoms:

You can also apply for one if you've been in contact with someone who's tested positive, or have been asked to test by your local council, contact tracers or a health professional.

The type you will be offered is called a PCR (polymerase chain reaction) test, which you can book online, or by calling 119 in England, Wales or Northern Ireland, or 0300 303 2713 in Scotland.

You then go to a drive-through or walk-through test site, or - if you are in the first few days of having symptoms - you can order a home testing kit.

Testing involves a swab up the nose and down the back of the throat. The sample is sent to a lab for analysis, with the result in 24-48 hours.

If you have symptoms everyone in your household must self-isolate until you get a negative result.

People without symptoms can also now get a "lateral flow" test, which gives results in 15-30 minutes.

This also involves swabbing your nose and/or throat, but the sample isn't sent away. Instead, the swab is dipped in a fluid which is dropped onto a plastic device, a bit like a pregnancy test.

A line appears on a paper strip to show the test has worked. A second line appears if you have the virus.

There are a number of ways to get a lateral flow test in England:

There is separate guidance for testing in Scotland, Wales, and Northern Ireland.

If you get a positive result from a lateral flow test, you must get a PCR test within two days to confirm the result.

If this is negative, you can stop isolating, unless you or someone in your household have developed symptoms in the meantime.

If you get a positive result from a PCR test, you and your household must self-isolate immediately, or face a fine.

You must not leave your house for any reason - even to buy food, medicines or other essentials, or for exercise.

Foreign holidays are not currently allowed, but people can travel if their journey meets government criteria. Many countries and airlines insist that passengers leaving the UK have a private coronavirus test within 72 hours of departure to get a so-called "Fit to Fly" certificate.

Similarly, returning travellers must also provide proof of a negative Covid-19 test taken within 72 hours and must then quarantine for 10 days.

They must test again on days two and eight of quarantine, at a cost of £210. If they test positive, they must self-isolate for a further 10 days, or face fines.

Under the "test to release" scheme, travellers from some countries can take a further test on day five of isolation.

People who test negative can stop isolating. Those who test positive must quarantine for 10 more days after the test.

Anyone using the scheme still has to take a further test on the eighth day.

Tests cost between £65 and £120.

With the most common type of PCR test, scientists at the University of Bristol believe 20% of positive cases could falsely appear as negative - wrongly telling someone they're not infected.

This could be because there were problems with the sample or in the lab, or because of the stage of infection the patient was at when tested.

Lateral flow tests are less sensitive than PCR tests, and can miss more cases, especially in people with mild infections.

However the government says that for every 1,000 lateral flow tests carried out, there was less than one false positive result.

False positives are equally rare for PCR tests.

But they can still cause problems. If lots of people get tested when there is very little virus in circulation, you might get more false positives than true positives, which can distort infection rates.