**6. Medical laboratory interventions in COVID-19**

As part of the global response to the COVID-19 pandemic, medical laboratory diagnosis has remained the corner stone to this intervention. Molecular assays performed on nasopharyngeal swab or other upper respiratory tract specimen are the most commonly used and reliable test for the diagnosis of COVID-19. A variety of RNA gene targets are used by different molecular assays.

The processes from sample collections, sample transport and actual testing for COVID-19 remains very important including all quality system measures put in place to ensure reliability and sensitivity. The medical laboratory research uses samples from nasopharyngeal swabs, oropharyngeal swabs, throat swabs, saliva, sputum, bronchoalveolar lavage fluid, conjunctival swabs, rectal swabs, whole blood, serum/plasma, stool, and urine [15].

It is evident that medical laboratory parameters have been adequately employed to access diagnosis like increased neutrophil, aspartate aminotransferase, alanine aminotransferase, C-reactive protein, lactate dehydrogenase and urea. There is also decrease in procalcitonin, albumin, and white blood cells like leukocytes, and lymphopenia and eosinopenia have been noted among COVID-19 patients. Also, medical

#### *Fighting COVID-19: The Medical Laboratory Involvement DOI: http://dx.doi.org/10.5772/intechopen.99459*

laboratory parameters have been employed in the assessment of the severity of the COVID-19 such as interleukin-6 (IL-6), d-dimer (d-D), glucose, fibrinogen, thrombin time, and C-reactive protein and fibrinogen. Some parameters are predictors during prognosis like IL-6 and D-Dimer, absolute lymphocyte count, lactate dehydrogenase, creatine kinase and absolute monocyte count which can predict whether the patient can be admitted into intensive care unit or not. During treatment, laboratory parameters are used to assess improvement in treatment and complications. For example; reduction in aspartate aminotransferase, alanine aminotransferase, creatine kinase and dehydrogenase shows response to treatment while increased procalcitonin and C-reactive protein indicates liver abnormality, high D-dimer, fibrinogen, prothrombin time predicts thromboembolism and new-onset renal failure [17, 20].

A medical laboratory, irrespective of location, modern, sophisticated or molecular in nature in the aspect of COVID-19 fight, has a huge role to play especially in the local certain where COVID19 testing has not reached. Many in such area may not know their status and no wonder the presence of a knowledgeable Scientist shall corroborate the medical laboratory implications of COVID-19 to be able to approach every client and sample in a safe and professional way.

There is always a manual that help members, states and partners as they set up comprehensive quality assurance measures for COVID-19 testing laboratory network. The guidance emphasizes the use of standardized registration formats as quality tool, Quality control (QC), enrollment of laboratories in external quality assessment (EQA) schemes and issues of external quality assessment performance data for continuous quality improvement of COVID-19 testing laboratories. It is an essential resource for a medical laboratory personnel to be involved in day-to-day testing of COVID-19.

**Figures 2** and **3** shows testing Algorithm for Nigeria while using RDTs and approved medical laboratories (75–25 Gene Xpert and 50 PCR Labs) for COVID-19 respectively as released by Nigeria Centre for Disease Control (NCDC).

In medical laboratory testing of COVID-19, each country adopts their protocol based on targeted proteins as it suits them based on available testing techniques and methodology and as well the laboratory set ups and environment. For instance,

**Figure 3.** *NCDC approved medical laboratories for COVID-19 as at 23rd February, 2021.*

USA protocol for testing targets N (N1, N2, N3) genes and Rp-RNase; China targets ORF 1ab and N-genes, Nigeria targets N-genes and ORF 1ab; Germany RdRp, E and N-genes, Japan and Thailand targets N-genes while Hong Kong targets ORF 1b-nsp-14 and N-genes [15, 17].
