SARS-CoV-2

The severe acute respiratory syndrome coronavirus 2, also known as SARS-CoV-2, is a strain of the coronavirus that is responsible for the respiratory ailment known as COVID-19 (coronavirus disease 2019). This illness is the cause of the continuing COVID-19 pandemic. The virus was referred to as human coronavirus 2019 and 2019 novel coronavirus (2019-nCoV) in the past. Its preliminary name was 2019 novel coronavirus (2019-nCoV) (HCoV-19 or hCoV-19). The World Health Organization (WHO) identified the outbreak for the first time in the city of Wuhan, which is located in the province of Hubei, China. On January 30, 2020, it declared the outbreak a Public Health Emergency of International Concern, and on March 11, 2020, it identified the outbreak as a pandemic. SARS-CoV-2 is an RNA virus with a single strand that reads in a positive direction and is infectious to humans.

The severe acute respiratory syndrome–related coronavirus (SARSr-CoV) species includes the SARS-CoV-2 virus, which is linked to the SARS-CoV-1 virus that was responsible for the SARS epidemic that occurred between 2002 and 2004. Despite its close relationship to SARS-CoV-1, its closest cousins, with whom it forms a sister group, are the derived SARS viruses BANAL-52 and RaTG13. With these viruses, it also has a tight genetic relationship. The available information suggests that it is most likely of zoonotic origins, and it has a close genetic relationship to bat coronaviruses, which suggests that it originated from a virus that was carried by bats. Ongoing research is attempting to determine if SARS-CoV2 originated directly from bats or whether it originated indirectly via any intermediary hosts. The virus has a low level of genetic variation, which suggests that the spillover event that introduced SARS-CoV2 to humans most likely took place in the latter half of 2019.

In the period from December 2019 to September 2020, epidemiological studies predict that each infection resulted in an average of 2.4 to 3.4 new ones when no members of the community are immune and no preventative measures are performed. On the other hand, some of the succeeding variations have a higher infectious potential. The virus is most likely to be passed from person to person via intimate contact. It may also be transmitted by aerosols and respiratory droplets that are expelled while talking, breathing, or otherwise exhaling, as well as those that are created when coughing or sneezing. It does this by attaching itself to a membrane protein called angiotensin-converting enzyme 2 (ACE2), which is responsible for regulating the renin–angiotensin pathway. This allows it to penetrate human cells.