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The testing deficit at the heart of the COVID-19 outbreak

Linda Nazarko takes stock of what we know of COVID-19 so far, and what we could be doing better

During an outbreak situation certain fundamental principles apply. These are to identify the causative organism, determine who is vulnerable, to test, trace, isolate and treat1.

When we became aware of the COVID-19 outbreak we should have made plans to contain the outbreak. This did not happen and The Lancet2 has described this as a ‘national scandal’. If only this lack of preparedness had been confined to one country... but this isn’t a national scandal it’s an international scandal.

COVID-19 is a coronavirus and it is thought to be transmitted through droplets generated by coughing and sneezing and through contact with contaminated surfaces3.

People who have compromised immune systems are at high risk of COVID-19. Those identified as being at greatest risk are people who have had an organ transplant, people having chemotherapy, people who have bone marrow or blood cancers, those with severe lung conditions, such as cystic fibrosis and severe asthma, people taking medication that impairs immune response, such as corticosteroids, and pregnant women who have a serious heart condition4.

People aged 70 and over are also considered vulnerable as ageing is known to impair the immune response and increase vulnerability to infection5,6. The risk of severe disease associated with COVID-19 for people in Europe is considered moderate for the general population and very high for older adults and individuals with chronic underlying conditions7.

When an outbreak occurs risk assessment is normally carried out. Then an investigation takes place this seeks to identify people affected, trace isolate and treat those affected and to protect those at risk8. Testing is normally the cornerstone of outbreak management however we have no idea of the global or national prevalence of COVID-19 because different countries have chosen different testing criteria. In the UK currently only people admitted to hospital are tested for COVID-19. The general population has been advised to stay at home and only to leave the house to shop for basic necessities such as food and medicine, to provide care to a vulnerable person, to exercise or to travel to and from work when this work is essential9.

The main symptoms of coronavirus (COVID-19) are a high temperature and a new, continuous cough. People who have symptoms are advised to self-isolate for 7 days if they live alone. If the person lives with others then the other members of the household must self-isolate for 14 days.

The absence of testing

In London anecdotal reports indicate that between 25-50% of NHS staff are absent from work due to illness or the requirement to self-isolate. No one would wish to spread COVID-19 but this policy combined with an absence of testing for staff is disastrous.

There are two types of tests, swabs and blood tests. A throat and nasal swab detects the presence of COVID-19 and lets the person tested, and the person’s household know if the person is infected. These tests are sent to a pathology laboratory and results are available within between 4-48 hours.

Blood tests detect the presence of antibodies and antigens. Antibody tests can be carried out at home by testing capillary blood and putting a test strip into a reader. The test gives a result in 15 minutes. Antibody tests check for COVID-19 antibodies and if the person is antibody positive this indicates that the person has been exposed to infection, have developed antibodies and has developed immunity.

An antigen test detects the presence (or absence) of an antigen. An antigen is a foreign substance that triggers an immune response. Antigens can be detected before the body has developed antibodies to a foreign substance such as COVID-19.

When tests will actually become available is unclear at present. But tests for NHS employees will start with critical care doctors and nurses and other intensive care staff, and staff in emergency departments, ambulance services and GPs. There are plans to test other NHS and essential workers as soon as possible10,11.

So when the testing finally begins, we will be be left with one crucial question: could it have been done sooner and would it have saved lives?

We urgently need to expand testing so that staff who are able to return to work can do so. We also need to be able to test staff and patients as quickly as possible so that people who are infected can be identified, isolated, observed and treated if treatment is required.

The first cases were reported in November 2019 and there were indications in December that a pandemic could occur. It seems that every nation in world failed to prepare for this pandemic. We must never let this happen again. When this is over we must reflect and learn lessons.

Linda Nazarko is a nurse consultant at West London NHS Trust

References

1.Data collection toolboxes [Internet]. Who.int. 2020 [cited 2 April 2020]. Available from: https://www.who.int/emergencies/outbreak-toolkit/d...

2. 2. Horton R. COVID-19 and the NHS—“a national scandal” [Internet]. the lancet.com. 2020 [cited 2 April 2020]. Available from: https://www.thelancet.com/journals/lancet/article/...

3. DHSC et.al. COVID-19: Guidance for infection prevention and control in healthcare settings. Adapted from Pandemic Influenza: Guidance for Infection prevention and control in healthcare settings. Issued jointly by the Department of Health and Social Care

(DHSC), Public Health Wales(PHW), Public Health Agency(PHA) Northern Ireland, Health Protection Scotland (HPS) and Public Health England as official guidance. 2020

https://assets.publishing.service.gov.uk/governmen...
4. Advice for people at higher risk - Coronavirus (COVID-19) [Internet]. nhs.uk. 2020 [cited 2 April 2020]. Available from: https://www.nhs.uk/conditions/coronavirus-COVID-19...

5. McDevitt M. Aging and the Blood. In: Filit H, Rockwood K, Young J, ed. by. Brocklehurst’s Textbook of Geriatric Medicine and Gerontology. 8th ed. Philadelphia PA: Elsevier; 2017. Chapter 24

6. Tummala MK, Taub DD, Ershler WB. Clinical immunology: immune senescence and the acquired immune deficiency of aging In: Fillit HM, Rockwood K, Young J, eds. Brocklehurst’s Textbook of Geriatric Medicine and Gerontology. 8th ed. Philadelphia, PA: Elsevier; 2017:chapter 93.

7. Rapid risk assessment: Coronavirus disease 2019 (COVID-19) pandemic: increased transmission in the EU/EEA and the UK – seventh update [Internet]. European Centre for Disease Prevention and Control. 2020 [cited 2 April 2020]. Available from: https://www.ecdc.europa.eu/en/publications-data/ra...

8. Public Health England [Internet]. Assets.publishing.service.gov.uk. 2020 [cited 2 April 2020]. Available from: https://assets.publishing.service.gov.uk/governmen...

9. Advice for everyone – Coronavirus (COVID-19) - NHS [Internet]. nhs.uk. 2020 [cited 2 April 2020]. Available from: https://www.nhs.uk/conditions/coronavirus-COVID-19...

10.How does a coronavirus home test kit work, and how do I get one? [Internet]. The Daily Telegraph. 2020 [cited 2 April 2020]. Available from: https://www.telegraph.co.uk/news/2020/04/02/covid-...

11. Devlin H. Frontline NHS staff first to receive new Covid-19 antigen tests [Internet]. the Guardian. 2020 [cited 2 April 2020]. Available from: https://www.theguardian.com/world/2020/mar/27/fron...