SARS-CoV-2

SARS-CoV-2 Coronavirus

During December 2019, the novel coronavirus Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2), was identified in China. As the name indicates, the virus is related to the SARS coronavirus (SARS-CoV) that caused deadly outbreaks in 2002-2003.

However, it is not the same virus.

On February 5, 2020, JAMA published a study focused on genetic sequencing data found the SARS-CoV-2 coronavirus shares 79.5% of the genetic sequence with SARS-CoV and has 96.2% homology to a bat coronavirus.

On February 11, 2020, the World Health Organization (WHO) announced the official name for the disease caused by SARS-CoV-2, Coronavirus Disease-2019 (COVID-19).

SARS-CoV-2 Symptoms

People infected with this new betacoronavirus have reported a wide range of symptoms reported – ranging from mild symptoms to severe illness - often appearing 2-14 days after exposure to the SARS-CoV-2 virus, says the U.S. CDC.

Recently, various studies have identified coronavirus disease 2019 (COVID-19) should be suspected when a severe reduction of either taste and/or smell is present in the absence of nasal obstruction.

Specifically, a study published in JAMA on June 18, 2020, found that the loss of taste and smell may be common symptoms among those in the early stages of SARS-CoV-2 coronavirus infection. And 40% of people lost their sense of smell or both taste and smell in the time between when they first realized they had symptoms and when a lab test confirmed infection.

SARS-CoV-2 Spreading

Based on what is currently known about this coronavirus, the CDC said on March 6, 2020, the transmission, in general, occurs much more commonly through respiratory droplets than through fomites. The spread from person-to-person happens most frequently among close contacts, living together, at home, or a nursing facility, and within 6-feet of distance.

On September 18, 2020, the CDC updated its guidance saying 'main way the virus causing COVID-19 is thought to spread mainly 'through respiratory droplets or small particles, such as those in aerosols, produced when an infected person coughs, sneezes, sings, and talks. These particles can be inhaled into the nose, mouth, airways, and lungs and cause infection.

The SARS-CoV-2 virus appears to spread more efficiently than influenza, but not as efficiently as measles, which is highly contagious, says the CDC.

A study published in Emerging Infectious Diseases on June 23, 2020, suggests that SARS-CoV-2 generally maintains infectivity at a respirable particle size over short distances, in contrast to either betacoronavirus, SARS-1, and MERS.

And, current evidence suggests that SARS-CoV-2 can remain viable for several hours on surfaces made from a variety of materials. Cleaning dirty surfaces followed by disinfection is the best measure to prevent respiratory illnesses in community settings. And, SARS-CoV-2 was more stable on plastic and stainless steel, than on copper and cardboard.

At this time, the risk of COVID-19 spreading from animals to people is considered to be low, says the CDC.

Who Is At Higher-Risk

Currently, there are limited data and information about the impact of underlying medical conditions and whether they increase the risk for severe illness from COVID-19. 'Based on what we know at this time, older people with the following conditions might be at an increased risk for severe illness from COVID-19.

While children have been less affected by COVID-19 compared to adults, children with certain conditions may be at increased risk for severe illness, says the CDC.

Children who are medically complex, who have serious genetic, neurologic, metabolic disorders, and congenital (since birth) heart disease might be at increased risk for severe illness from COVID-19. Similar to adults, children with obesity, diabetes, asthma, and chronic lung disease, or immunosuppression might be at increased risk for severe illness from COVID-19. 

SARS-CoV-2 Vaccines

The SARS-CoV-2 vaccine development efforts include platforms such as nucleic acid, virus-like particle, peptide, viral vector (replicating and non-replicating), recombinant protein, live attenuated virus, an inactivated virus approaches. Detailed vaccine development information can be found on this webpage.

SARS-CoV-2 Sunlight and Swimming

The U.S. CDC published updated various considerations as some communities in the USA consider opening public beaches. On July 30, 2020, the CDC stated 'evidence suggests that COVID-19 cannot be spread to humans through most recreational water.'

And on June 12, 2020, the US Department of Homeland Security Science and Technology (S&T) Directorate added a new calculator that estimates the natural decay of the SARS-CoV-2 virus in the air, such as when visiting a breach, and 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 Coronavirus Origin

The SARS-CoV-2 virus is a betacoronavirus, like MERS-CoV and SARS-CoV, both of which have their origins in bats. The sequences from U.S. patients are similar to those China patients initially posted, suggesting a recent emergence of this virus from an animal reservoir, such as horseshoe bats (Rhinolophus sinicus).

And a recent paper published by Lu Jian of Peking University and colleagues on March 3, 2020, analyzed 103 virus genomes and argued that they fell into one of two distinct types, named S and L, distinguished by two mutations. Because 70% of sequenced SARS-CoV-2 genomes belong to L, the newer type, the authors concluded that the virus has evolved.

As of April 30, 2020, researchers had identified 14 mutations in a study tracking of the SARS-CoV-2 coronavirus. 

In early July 2020, a study published in Cell reported that a SARS-CoV-2 variant in the spike protein, D614G, rapidly became dominant around the world. While clinical and in vitro data suggest that D614G changes the virus phenotype, the impact of the mutation on transmission, disease, and vaccine and therapeutic development are largely unknown.

And in a study published on July 28, 2020, an international research team of Chinese, European, and U.S. scientists announced they have discovered that the lineage that gave rise to the coronavirus has been circulating in bats for decades and likely includes other viruses, with the ability to infect humans.

SARS-CoV-2 Wastewater Detection

People infected with SARS-CoV-2 shed the virus in their stool even before they show symptoms of COVID-19. Analyzing sewage for the virus, using methods like the ones used for testing individuals, can predict the community level of infection 4-days to 1-week in advance of clinical diagnoses, and show increasing and decreasing levels of coronavirus infection and transmission.

A study published on September 18, 2020, measured SARS-CoV-2 RNA concentrations in primary sewage sludge in the New Haven, Connecticut, during the Spring of 2020. SARS-CoV-2 RNA was detected throughout the study.

Recently, US states, such as Colorado and Ohio have taken steps toward implementing wastewater surveillance efforts.

On August 7, 2020, the WHO stated the detection of non-infective RNA fragments of SARS-CoV-2 in untreated wastewater and/or sludge has been reported in a number of settings, such as Milan, Italy; Murcia, Spain; Brisbane, Australia; multiple locations in the Netherlands; and Paris, France.

According to University of Barcelona virologists study published on June 13, 2020, traces of the SARS-CoV-2 virus were found in a sample of Barcelona wastewater collected in March 2019.

SARS-CoV-2 FAQs

NOTE: The content on this page is sourced from the CDC, WHO, clinicaltrials.gov, and the Precision Vax network of websites. This information was last fact-checked by healthcare providers, such as Dr. Robert Carlson.