Difference Between Coronavirus Specie, Strain and Variant

Strain, specie and variant

Before the Covid-19 pandemic, most people only talked about viruses in general. Very few people knew about terminologies used when talking about viruses. Only those who studied genetic engineering and related courses did.

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When the news of a new variant strain of the virus causing Covid-19 surfaced in the United Kingdom (UK) and South Africa, many news media used the term strain. Others use the term variant. This confusion can easily be cleared.

What Is Strain, Specie and Variant

To understand what these terms of a virus means, we will use coronavirus to explain it. Coronavirus are a large group of viruses that affect both birds and mammals. There are hundreds of coronavirus. Only seven specie affect people. Three are of economic importance.

Classification of living things has seven levels which starts from kingdom and ends in species. The name coronavirus is a genus and split into four genera which are alphacoronavirus, betacoronavirus, deltacoronavirus and gamma coronavirus. The name is used to refer to any member of the subfamily ortho coronaviridae.

The name was derived from their outer shape. They all have a spiky projection on their surface similar to corona on the sun or spike on a crown. Corona is a Latin word which means crown.

After genus, the next level is species. Severe acute respiratory syndrome-related coronavirus is the species where the strain severe acute respiratory syndrome coronavirus (SARS-CoV) and severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) falls into. So both SARS-CoV and SARS-CoV-2 are the name of the virus in the species belonging to different strains. SARS-CoV causes SARS disease while SARS-CoV-2 causes Covid-19 disease. There are others in the species too.

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Same species can mate to reproduce. To explain, we all are homo sapiens species' and can mate to produce offspring. A strain refers to a genetic variant or subtype of a biological species. A strain such as SARS-CoV and SARS-CoV-2 can mutate into another variant. There are several variants of SARS-CoV- 2 already. But some are not of importance because the change occurs in a very small part that is not significant. They are most likely to be affected by the same drug or vaccine. A new variant may affect the spike or other parts. According to a research by Takahiko Katana, et al between February 1 and May 1, 2020, several variants of SARS-CoV-2 were found but only D614G clade has become the most common variant since 2019. The new variant discovered in the UK and South Africa may be significant.