Jan 12, 2021
According to the Centers for Disease Control and Prevention (CDC), there are two kinds of tests available for COVID-19: viral test and antibody test. The viral or molecular test determines if a patient is actively infected with SARS-CoV-2, samples are collected through nasopharyngeal swabbing. On the other hand, the antibody or serology test also known as test for past infection, reveals if a patient has been exposed to the virus through blood samples. Most of the tests being rolled out against COVID-19 are viral tests based on reverse transcription. Collected samples should ideally be placed in a sterile transport tube immediately or on ice and special media to prevent degradation since the genetic material of SARS-CoV-2 is fragile and transient.
Figure 1. Viral Testing (Nucleic Acid Detection) Diagnose Active SARS-CoV-2 Infections Source: American Society for Microbiology
In contrast, the antibody test targets the immune response of infected person—detecting antibodies against the virus instead of detecting the viral genetic material. Although this test can give the result within an hour, most professionals claim that this type of test is not as accurate as viral testing. The problem is that antibodies only develop several weeks after an infection, which means that an antibody-based test is not recommended for early diagnosis and it might miss asymptomatic cases.
Figure 2. Antibody Test (Serology) Detect Immune Response to SARS-CoV-2 Exposure Source: American Society for Microbiology
Outlined below are the viral testing components for the CDC COVID-19 protocol “Centers for Disease Control and Prevention (CDC) 2019-Novel Coronavirus (2019-nCoV) Real-Time Reverse Transcriptase (RT)-PCR Diagnostic Panel:
Testing laboratories will need the following supplies dependent to the elements of the virus test kit provided by the CDC to run the COVID-19 test. To guarantee total compliance, secure that there will be no missing component.
Aside from the consumables, laboratories must also create an environment conducive to monitoring and carrying out the viral test. Laboratories that routinely conduct polymerase chain reactions likely conform to the environmental conditions. If not, the following equipment are essential for successful input in the coronavirus test.
Efficiently mixes small volumes of liquids.
Adjustable calibrated instruments used with disposable sterile tips to transfer small quantities of liquid.
Adjustable calibrated instruments used with disposable sterile tips to transfer multiple samples of small quantities of liquid at a time.
Secure sample tubes and maintain a cool temperature while reagents and samples are added.
Combines adjustable automated PCR cycling with optical detection technology.
On top of the specified list of consumables and equipment required, CDC emphasized that viral isolation from specimens collected from people suspected to have COVID-19 should be performed by staff trained in the relevant technical and safety procedures in BSL-2 and BSL-3 laboratories. Otherwise, clinical laboratories should not attempt to conduct the viral isolation. World Health Organization (WHO) also added that national guidelines on laboratory biosafety should be followed in all circumstances. Corresponding to this, WHO released Laboratory Biosafety Guidelines for Handling and Processing Specimens Associated with COVID-19 and discoursed the following Good Microbiological Practice and Procedure (GMPP) as a core requirement in non-propagative diagnostic laboratory work (e.g. sequencing, NAAT).
When these practices are strictly implemented and the right laboratory equipment are used, the likelihood of exposure of personnel when handling or manipulating biological agents will be minimized.
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