COVID-19

Family: coronavirus, sub-genusL sarbecoronavirus, Beta coronavirus, lineage B (frequent recombination)

Thousands of variants, grouped into clades (Nexstrain: 5, GISAID: 7). Variants of concern:

  • Alpha: B.1.1.7

  • Beta: 1.3.51

  • Gamma: P1

  • Delta: B.1.617.2

  • Omicron: B.11.529

  • ....

Diagnosis

Viral nucleic acid dection

  • RT-PCR: detects genetic material of the virus/amplifies (replicates) a small, well-defined segment of RNA, creating enough for analysis

  • Isothermal amplification e.g. CRISPR

Viral antigen detection

  • Ag rapid diagnostic test (RDT): detects viral proteins (performance best in first 5-7 days of symptoms). Bind to artificial antibodies designed to bind to coronavirus antigens (e.g. on nucleocapsid or spike protein)

Antibody detection

  • Rapid test/rapid chromatographic immunoassay: sample reacts with COVID-19 antigen-coated on the test strip

  • Serologic test: detects human antibodies against the virus

Other

  • Imaging