SARS-CoV-2 is a humanborne coronavirus in the betacoronavirus family. The emergence of SARS-CoV-2 led to the SARS-CoV-2 pandemic to be declared by the World Health Organization.
SARS-CoV-2 stands for Severe Acute Respiratory Syndrome Coronavirus 2. It is named as such due to its relative similarity to the SARS coronavirus that led to a public health emergency in parts of the world in 2003.1) 2)
The SARS-CoV-2 virus is a close genetic relative of two other infamous viruses from recent history: SARS-CoV and MERS-CoV.3)
threadreader for inage 4)
SARS-CoV-2 is a positively charged, single-stranded RNA virus.
Researchers have found in autopsies that SARS-CoV-2 does get into brain tissue, and can be present for months after infection, though inflammation outside of the lungs was mild.6)
See Spike Protein for a discussion of toxins.
Nearly two years into the COVID-19 pandemic, some aspects of transmission is still debated. Contact tracing research out of China showed no asymptomatic viral transmission at all.7) Other research indicates that symptomatic transmission drives the pandemic, but there may be smaller amounts of asymptomatic and presymptomatic spread.8) 9) 10)
Further reading:
Throughout the pandemic, evidence has piled up suggesting that all or nearly all SARS-CoV-2 tranmission takes place through aerosolized virion particles.12) While Goldberg drum experiments suggested that SARS-CoV-2 could hang in the air for up to three hours,13) more sophisticated experiments showed SARS-CoV-2 aerosols to be viable for only around 20 minutes.14)
SARS-CoV-2 is a highly aerosolized virus, and research shows that nearly all transmission takes place in indoor settings where a poorly ventilated room can fill to a pressurized level with virions. One study (preprint) found that 95% of primary case transmission in Japan took place in closed environments.15)
= Transmission among Children and in Schools = Early during the pandemic, there was great debate over whether or not children could transmit SARS-CoV-2 to adults. If they cannot, then they likely cannot generate viral loads enough to get sick. It is likely that they rarely, but sometimes do develop sufficient viral load to get sick and also transmit, but this may happen most off with children who are immunodeficient or immunocompromised.
Early during the COVID-19 pandemic, many laboratories euthanized mice as a preventative measure.17)
At least one research team argues that there is evidence of infection and shed from the human gastrointestinal tract.18)
ACE2 and TMPRSS2 and bears, oh my!
Some research indicates neuroinvasion of SARS-CoV-2: https://www.youtube.com/watch?v=fNFzfwLM72c&t=2s
Once inside the body, SARS-CoV-2 may infect human adipose tissue, which may be one of the reasons obesity is so highly associated with the COVID-19 disease state and long haul COVID-19 symptoms.19)
COVID-19 animal infection tracker
Numerous animals aside from humans have been noted to be susceptible to SARS-CoV-2 infection. Comparative and structural analysis on 410 vertebrate species predicts a broad host range for infection, specifically among mammals.20) One study still in preprint found SARS-CoV-2 moving rapidly into white-tailed deer populations in North America, with over 80% of the deer testing PCR positive for the virus by early 2021.21)
There are competing theories on how people can build immunity to SARS-CoV-2 infection or the resulting COVID-19 disease state.
Herd immunity is the condition in which viral outbreaks become rare due to sufficiently low transmission rates of a pathogen. This topic has become controversial during the SARS-CoV-2 pandemic due to a combination of propaganda and changing transmission rates of SARS-CoV-2 variants of interest.
See natural immunity.
During the early part of the COVID-19 pandemic, physicians and scientists found that reinfections were extremely rare.22)
During the omicron era, reinfections are rapidly on the rise.23)
Scientists have noted evidence for aerosol transfer of SARS-CoV-2-specific humoral immunity.24)
SARS-CoV-2 is a cause of COVID-19, a disease with wide ranging characteristics primarily affecting the respiratory and vascular systems.
There is debate over the nature of the mutations of SARS-CoV-2, its causes, and the implications. This includes theories that non-sterile COVID-19 vaccines sift virions, generating immunity escape.
See more at SARS-CoV-2 Variants
The origins of SARS-CoV-2 are shrowded in mystery, including whether the virus is zoonotic or manmade, or was released accidentially or intentionaly.
Many papers have been retracted during the COVID-19 pandemic. Here are some that relate specifically to SARS-CoV-2, though others may be found at Retraction Watch.