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Testing for Covid-19: Your questions answered



The UK is now in its fourth week of nationwide lockdown. With a vaccine for the new coronavirus 18- 24 months away, scientific experts have stated that the UK must increase its testing capacity if life is to return to normal anytime soon.

The UK is now in its fourth week of nationwide lockdown. With a vaccine for the new coronavirus 18- 24 months away, scientific experts have stated that the UK must increase its testing capacity for Covid-19 if life is to return to normal anytime soon. With the help of the most recent scientific literature, Nursing in Practice in the Q and A below looks at Government’s testing policy, the Covid-19 tests available and what this means for primary care.

How is the Government currently testing for Covid-19?  

The UK’s Covid-19 testing policy is decided by the Chief Medical Officer and Public Health England (PHE). The Government stated they are currently testing 14,000 people a day. The tests available are prioritised for patients admitted to hospitals with suspected Covid-19 and NHS staff.

Frontline healthcare staff tested include those working in critical care, emergency departments, and ambulance services. As of this week, care home staff and symptomatic residents will also be tested. If a high priority NHS worker is self-isolating because their family has Covid-19, they can also undertake a test where possible, to enable all who can be to be at work.

PHE said that the testing would continue as a phased approach, with the continued priority of hospital inpatients with suspected Covid-19 and NHS workers and their families. Testing will then be expanding to critical key workers and, ultimately, the wider community over time.

The Government has committed to reaching 100 000 tests per day by the end of April.

What type of testing is currently available for Covid-19?

Those tested undergo nasal or throat swab tests in a hospital, which are then sent away for laboratory testing. The swab test is a type of diagnostic test and can only indicate if a person has the virus at that specific time, not if they have had it and recovered.

Specialist laboratories, which use polymerase chain reaction (PCR) machines, can detect whether the genetic material of the virus is present in the sample and thus whether a person has Covid-19 or not.  Results can take up to 72 hours to obtain.

The swab test is currently the best indicator of Covid-19 approved for use in the UK. However, false negatives are reported at a rate of 30% due to low levels of the virus in the early onset of the disease or poor testing techniques. These tests are better used to confirm the presence of the infection, rather than give a patient or health worker the all-clear.

Could other tests be of use?  

Antibody tests are an alternative type of test used to see if a person has been infected by Covid-19 and has immunity. The test determines whether a person’s blood contains Covid-19 antibodies and can be undertaken at home with a finger prick. The tests are cheap at £6, and results are available within 20 minutes.

The Government is working to determine how useful these antibody tests could be and are partnering with private companies who already offer the tests. Antibody tests are helpful for people who think they have had Covid-19 or people who may have been infected but remained asymptomatic. If a test detects Covid-19 antibodies, a person could safely return to work and resume life without putting themselves or their community at risk.

Covid-19 is a very new disease, and so the development of an antibody test has only just begun. Scientists are rushing to find a useful test that can be rolled out globally.

How do antibody tests work?

The antibody test detects the presence or absence of antibodies within a person’s blood. Antibodies are produced when the body is infected with a virus and mounts an immune response to fight off the infection. They do not detect the virus itself, rather the body’s defence against the virus.

The presence of Covid-19 antibodies in a person’s blood indicates immunity to the virus. It is hoped that mass antibody testing could provide the way out of lockdown for the UK.

Antibody tests are not widely available anywhere in the world. Scientists at the University of Oxford are testing commercially available antibody tests for the UK government. The researchers have stated that no antibody test is yet available which has the necessary characteristics for screening people accurately for Covid-19.

How is the Government going to increase testing capacity?

Increased testing capacity will come from the ability to undertake more swab tests for sick patients and NHS staff, and from the development of an effective antibody test to assess immunity in the wider population.

Most swab tests are currently being undertaken by centralised NHS laboratories. Over the next few weeks hospitals will increase their onsite PCR capacity in order to provide a quicker method of attaining results from Covid-19 swab tests.

The Government is working with universities, research institutes, and private companies, such as Boots and Amazon, to develop a new network of labs and testing sites across the UK. Universities have donated equipment and volunteered staff time to help at the testing facilities such as the newly opened Government laboratory in Milton Keynes.

The overall aim is to build a large-scale diagnostics industry that is lacking in the UK. By bringing together universities, public bodies, and private companies during this outbreak, the Government will build a testing capacity that can be called on in the likely event of future coronavirus pandemics.

Testing of commercially available antibody kits is also continuing.

Are there any home testing kits currently approved for use?

Several commercial companies are offering Covid-19 home swab testing as a private service. They can be as much as £249.99 per test, with discounts available for NHS workers.

There are currently no home testing antibody kits that have been approved by the Government for use. The Medicines and Healthcare products Regulatory Agency (MHRA) have shut down nine online traders selling unlicensed Covid-19 products, which include antibody home testing kits.

How would testing help GP surgeries?

As of 4 April 4,500 NHS workers had been tested for Covid-19, but the Government is committed to providing tests for all frontline NHS workers, including those in primary care. Countrywide testing for general practice staff who have been self-isolating began last week.

The development of the antibody test will enable all surgery staff to determine whether they have been infected with Covid-19 quickly and to continue their work safely.

Sources:

·       Testing is the only way get out of lockdown: Professor Julian Peton in The BMJ

·       Testing of NHS staff and scaling up testing programmes

·       100 000 tests by the end of April

·       Government advise against the use of home testing kits

·       Call for GP surgeries to have tests available from NHS England

·       Good quality testing can help return to normal life and 4500 NHS workers tested as of 4 April

·       30% false negative swab tests and accuracy for antigen tests, antigen tests more accurate than swab tests and cost of antigen tests

·       Compilation of testing rates by country:

·       Unregulated online traders selling unapproved tests

·       £249 tests

·       Inaccurate antibody tests

·       Tests for primary care

·       Testing of GP practices began last week

·       Chats with scientists: Professor Julian Peto, London School of Hygiene and Tropical Medicine.