Covid: What is the mass test and how does it work?

A coronavirus mass testing program has been set up in Liverpool.

There are now plans to expand it to other parts of England and to students before they return home for Christmas.

How do mass tests work and what are they used for?

Mass screening means asking everyone to get tested, whether or not they have symptoms.

The idea is to find healthy people who can be infected, but who are not yet showing symptoms. They can then be told to isolate and stop spreading the virus.

Currently, in most of England, people can only be tested if they already have symptoms. But during the Liverpool pilot, everyone who lives or works in the city is offered a voluntary test.

Mass testing can be used in more targeted ways, including:

Mobile testing sites have been set up across Liverpool, in places like nursing homes, schools, universities and workplaces.

Local authorities can invite people to come for a test, but they can also book theirs online, or entire families can just show up in their cars.

Around 2,000 soldiers are involved in logistics and providing tests at 85 potential sites.

More than 23,000 people have been tested in Liverpool since the start of the pilot project, and 154 people have tested positive. The city has about half a million inhabitants.

There are now plans to expand the program to other regions and Nottinghamshire is next on the list, according to the BBC.

Health Secretary Matt Hancock said rapid tests are being sent to 67 local directors of public health, including those in Yorkshire, the West Midlands, other parts of the North West and across the northeast.

A week of mass testing at English universities starting November 30 could allow students to return home safely for Christmas, according to a letter from the universities minister to the vice-chancellors.

NHS staff will also start being tested for the coronavirus twice a week. Routine tests on health workers are already taking place in areas hardest hit by the virus.

The Liverpool pilot offers two types of tests, both involving a swab from the nose or throat – a PCR (polymerase chain reaction) test and a lateral flow test.

The PCR test is considered the “gold standard” by epidemiologists, but can take up to a day or more to produce a result when the sample is sent to a laboratory. It is, however, the most widely used one in the world.

The lateral flow test involves a portable kit that gives a result – much like a pregnancy test – in about 20 minutes, without the need for a lab. Fluid from a nasal swab or saliva goes to one end, then a marking appears if you are positive.

Liverpool’s director of public health Matthew Ashton said the city has the capacity to perform 50,000 lateral flow tests and 14,000 PCR tests per day.

Anyone who tests positive during the pilot must self-isolate immediately for at least 10 days. Their contacts will be traced by NHS Test and Trace.

Everyone else in their household should also self-isolate for 14 days from the day the person first became ill, or the day of the test, if they have no symptoms.

Self-isolating means staying at home and not leaving it even to buy food, medicine or other essentials, or to exercise.

People should order groceries online or ask friends or family for help by getting what they need and leaving the items outside the door.

Anyone in England who fails to self-isolate after testing positive can be fined up to £ 10,000.

Anyone on low income who has been instructed to self-isolate during a phone call from the NHS Test and Trace should be able to claim a payment of £ 500 from their local authority.

In September, Mr Johnson presented his “moonshot” plan to control the virus with mass testing, possibly next spring.

He said that “in the near future” he wanted to start using the tests to allow people who test negative “to behave in a more normal way.”

Other countries have already introduced mass testing programs.