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September 15, 2022

Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2)

The coronavirus Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) was identified in China in 2019 and earlier in Africa, then confirmed by the World Health Organization (WHO) in 2020. As the name indicates, this coronavirus is related to the SARS beta coronavirus (SARS-1) that caused fatal outbreaks in 2002-2003. However, it is not the same virus.

In molecular epidemiology, a study published on May 4, 2021, found the progenitor genome (proCoV2) is the mother of known SARS-CoV-2 coronaviruses. These researchers estimate that the SARS-CoV-2 progenitor was in circulation several weeks before the first genome sequenced in China, known as Wuhan-1, stated Sayaka Miura, a study's senior author.

On July 22, 2022, ‘Special Report’ anchor Bret Baier presented on YouTube the timeline of how U.S. government officials responded to information about coronavirus origins.

SARS-CoV-2 Variants

The coronavirus that causes COVID-19 is mutating, which is expected as viruses mutate as they spread, stated the U.S. CDC. The original SARS-CoV-2 strain, detected in Wuhan, China, in December 2019, is the L virus strain. This human coronavirus (hCOV) has since mutated. 

For example, the peer-review journal Nature published the findings from a recent study on July 5, 2022 - Antibody evasion by SARS-CoV-2 Omicron subvariants BA.2.12.1, BA.4, & BA.5. 'The Omicron lineage of SARS-CoV-2 continues to evolve, successively yielding subvariants that are not only more transmissible but also more evasive to antibodies.' In addition, Nature previously published a study on March 17, 2022, that stated 'it is known that the SARS-CoV-2 Omicron variant encodes 37 amino acid substitutions (including insertions and deletions) in the spike protein, and then the recombination event alone leads to 22 of them. And it has been reported that these substitutions have led to subtle variations in the spatial structure and the affinity to the hACE2 receptor of the spike protein. But, more importantly, it has caused the immune escape of the Omicron variant to the available vaccines and antibody therapeutics.'

On March 14, 2022, the Global Initiative on Sharing All Influenza Data (GISAID) provided data indicating it has been circulating since early January 2022. The analysis confirms the structure of a recombinant virus derived from the GK/AY.4 and GRA/BA.1 lineages. As of May 17, 2022, the "Delta" (L452R) mutation was found in both the BA.2.12.1 and BA.4/BA.5 variants is key to both immune escape and enhanced cell fusion (not present in BA.1 or BA.2).

SARS-CoV-2 Transmission

The U.S. CDC suggested on June 7, 2022, that ensuring ventilation improvement resources might reduce transmission of SARS-CoV-2 and other infectious diseases in schools. However, air transmission of the SARS-CoV-2 virus was 1000% higher than surface transmission at the University of Michigan, according to a study published by researchers at U-M's School of Public Health on April 27, 2022. They found the probability for infection was about 1 per 100 exposures to SARS-CoV-2 aerosols through inhalation and as high as 1 in 100,000 from contaminated surfaces in simulated scenarios.

On April 29, 2022, a modeling study published in the Nature Microbiology journal found that Daily infectious SARS-CoV-2 virus shedding varied substantially among newly diagnosed asymptomatic or mildly ill people, suggesting individual differences in viral loads and clearance kinetics may account for "superspreading." And a study published by the Journal of Aerosol Science 'observed that the air around COVID-19 patients frequently showed the presence of SARS-CoV-2 RNA in both hospital and indoor residential settings, and the positivity rate was higher when two or more COVID-19 patients occupied the room.' 

The U.S. Administration confirmed on March 23, 2022, that the most common way COVID-19 is transmitted from one person to another is through tiny airborne particles of the virus hanging in indoor air for minutes or hours after an infected person has been there.

SARS-CoV-2 positivity rates were found in a BMJ analysis and meta-study review on March 16, 2022, to be low in babies born to mothers with SARS-CoV-2 infection. Evidence suggests confirmed vertical transmission of SARS-CoV-2, although this is likely rare.

SARS-CoV-2 Infectious Rate

On May 5, 2022, researchers found that most children aged 1–17 had probably been infected by February 2022, and those aged 5 to 11 reached the highest level of 77%. On April 26, 2022, the U.S. CDC announced that about 75% of children had serologic evidence of previous infection with the SARS-CoV-2 coronavirus as of February 2022. 

SARS-CoV-2 Diagnostic Tests

The COVID-19 tests most people discuss are RT-PCR, the nasal-swab test that detects viral RNA, and various antibody tests that see if you have an immune response due to past exposure to the SARS-CoV-2 virus. The first SARS-CoV-2 test kits under a EUA were distributed on February 7, 2020. For updated coronavirus test news, please visit 'Tests.'

SARS-CoV-2 Sunlight and Swimming

The U.S. CDC stated, 'evidence suggests that the SARS-CoV-2 virus cannot be spread to humans through most recreational water.' And on June 12, 2020, the U.S. Department of Homeland Security Science and Technology (S&T) Directorate added a calculator that estimates the natural decay of the SARS-CoV-2 virus in the air, such as when visiting a breach found the coronavirus was least stable in the presence of sunlight. This new S&T research has been featured in the Oxford Academic Journal of Infectious Diseases, with the most recent – Airborne SARS-CoV-2 is Rapidly Inactivated by Simulated Sunlight.

SARS-CoV-2 Detected in Wastewater

The U.S. CDC published: Early Evidence of the SARS-CoV-2 B.1.1.529 (Omicron) Variant in Community Wastewater — United States, November–December 2021. This report describes the initial detections of SARS-CoV-2 in wastewater. In Italy, SARS-CoV-2 was found in sewage samples collected between the end of February (after the first autochthonous case) and April 2020 (La Rosa et al., 2020). (see: Ahmed et al., 2020; Bar Or et al., 2020; La Rosa et al., 2020; Medema et al., 2020; Nemudryi et al., 2020; Randazzo et al., 2020a, Randazzo et al., 2020b; Wu et al., 2020b; Wurtzer et al., 2020). 

The peer-review journal ScienceDirect published- Molecular evidence for SARS-CoV-2 in samples collected from patients with morbilliform eruptions since late 2019 in Lombardy, northern Italy, Volume 215, Part 1, December 2022, 113979... that viruses with mutations characterizing B.1 strain may have been spreading globally before the first Wuhan outbreak in later 2019.

The University of California, Merced, laboratory’s COVIDPoops19 dashboard tracks about 3,563 testing sites in 70 countries.

Early SARS-Like Research

March 14, 2016 - The peer-review journal PNAS published RESEARCH ARTICLE - SARS-like WIV1-CoV poised for human emergence. The data highlight the utility of a platform to identify and prioritize prepandemic strains harbored in animal reservoirs and document the threat posed by WIV1-CoV for emergence in human populations.

November 9, 2015 - The peer-review journal Nature published: A SARS-like cluster of circulating bat coronaviruses shows potential for human emergence.  Our work suggests a potential risk of SARS-CoV re-emergence from viruses currently circulating in bat populations.

SARS-CoV-2 Coronavirus FAQs

NOTE: This page's content is sourced from the CDC, WHO,, and the Precision Vax network of websites. Healthcare providers fact-checked this information.