What is Genomic Surveillance?
“All viruses change (or mutate) as they replicate and spread in a population. Viruses that have RNA as genetic material, such as SARS-CoV-2 (the virus that causes COVID-19) and influenza, mutate much faster than viruses with DNA. Every time SARS-CoV-2 replicates, there is an opportunity for the virus to change. Many mutations do not affect the virus’s ability to spread or cause disease because they do not alter the major proteins involved in infection and transmission.
When one of these changes does affect the virus’s ability to spread or cause disease, there may be a competitive advantage over the other lineages of SARS-CoV-2. Over time, certain lineages with these advantages become more prevalent and circulate in a population. When a lineage or group of lineages have characteristics that impact public health, CDC may classify them as a “variant of interest”, or “variant of concern”. – CDC