Written By: Longjam Dineshwori | Updated : July 28, 2020 9:23 AM IST
SARS is considered to be much more deadly than COVID-19.
The novel coronavirus that causes COVID-19 and SARS-CoV, the virus that was responsible for the severe acute respiratory syndrome (SARS) outbreak in 2003, belong to the same coronavirus family. The two viruses are similar in many ways. For example, they both lead to respiratory illnesses and are spread through respiratory droplets. Both SARS-CoV-2 and SARS-CoV are believed to have originated in bats, and transmitted to humans via an intermediate animal host. Researchers have found another similarity between the two viruses they have almost identical protein.
This finding could improve the outcomes for COVID-19 patients experiencing severe respiratory symptoms - the researchers suggested in a paper published in journal Frontiers in Cellular and Infection Microbiology.
For the study, they compared the genomes of 24 Betacoronaviruses, including four SARS-CoV-2 viruses, which cause COVID-19. Two strains of the novel coronavirus were sequenced in the US, while the other two in China.
"The research team wanted to understand the genetic makeup of SARS-CoV-2. Seeing what has changed might help find ways to detect the virus and understand its rapid spread. Seeing what remains conserved between these viruses might help predict if therapeutic approaches developed for other Betacoronaviruses could work on SARS-CoV-2," IANS quoted first author Intikhab Alam from King Abdullah University of Science and Technology in Saudi Arabia as saying.
After genomic comparisons and structural analyses, the researchers found a small protein that extends across the viral membrane, called envelope protein E, to be almost identical in SARS-CoV-2 and the SARS virus (called SARS-CoV-1).
According to scientists studying the SARS-CoV-1, a molecular component of this envelope protein E helps the virus release inflammation-causing substances in its host. This inflammatory reaction then causes accumulation of fluids in the lungs, which makes the infected person difficult to breathe, a condition called acute respiratory distress syndrome. Scientists have found that certain drugs approved by the FDA can inhibit this reaction in mice.
Alam believes that drugs that inhibit the envelope protein E of previous SARS viruses may also be able to block the protein in Covid-19.
"Even though these drugs won't stop the virus from spreading, we hope they could attenuate or prevent acute respiratory distress syndrome and help save lives," he added.
Though the viruses that cause these diseases share many similarities, SARS is believed to be more severe than COVID-19. As per estimates, 20 percent of COVID-19 patients need hospitalization and a smaller percentage of this group needs mechanical ventilation. In the case of the SARS outbreak, 20 to 30 percent of patients required mechanical ventilation.
SARS is also considered to be much more deadly than COVID-19. While mortality rates for COVID-19 are estimated to range between 0.25 and 3 percent, it is about 10 percent in SARS.
According to experts, COVID-19 spreads more easily than SARS. This is apparently because of more viral load in the nose and throat of people with COVID-19 since the initial stage of the disease. In the case of SARS, the viral loads peaked much later in the illness. Some research suggests that asymptomatic COVID-19 patients can also spread the disease. However, there had been no cases of SARS transmission before symptom development.
With inputs from IANS
