COVID-19: Researchers evaluate reason behind greater transmission in coronavirus variants

A new study by Johns Hopkins School of Medicine has determined the reason behind the higher transference of COVID-19 as the patients with two SARS-CoV-2 variants associated with the greater transmission, do not show any evidence of having higher viral loads in their upper respiratory tracts compared to the control group. Looking into the enhanced transmission of variants of SARS-CoV-2 that causes COVID-19, the researchers investigated B.1.1.7 (identified first in the UK) and B.1.351 (identified first in South Africa). The researchers evaluated if patients showed higher viral loads, and consequently increased shedding and transmissibility. 

As per news agency ANI, for the study, the experts identified the variants by using whole-genome sequencing. Further, they used a large cohort of samples to show that B.1.1.7 constituted 75% of the circulating viruses by April 2021. The researchers compared at least 134 variant samples to 126 control samples and correlated the genomic data with the clinical disease and repercussions through the patients’ clinical information.  All the collected samples underwent additional testing to determine the viral load and the information was reportedly associated with the stage of the disease by looking at the data after the onset of COVID-19 symptoms. Reportedly, it further enhanced the clarity in the comparison of viral shedding between the groups.

"The reason why these variants show higher transmissibility is not yet clear," said Adannaya Amadi, lead author of the study, as per ANI. "However, our findings did show that the patients infected with these variants are less likely to be asymptomatic compared to the control group. Although those infected with the variants were not at higher risk for death or intensive care admission, they were more likely to be hospitalized."

The study was performed at Dr. Heba Mostafa’s research laboratory at Johns Hopkins School of Medicine which has been reportedly performing large-scale whole-genome sequencing of SARS-CoV-2. It is being done for the State of Maryland and contributes the data to the national publicly available surveillance figures. 

COVID-19 Patients Suffer Loss Of Brain's Grey Matter

Meanwhile, apart from widely reported aftereffects of COVID-19 infection including loss of senses of taste and smell, ‘brain fog’, UK study has now found out that patients who recovered even from mild or moderate infection were seen have suffered some loss of grey matter in the areas that monitor cognitive skills, memory-making, sensory functions. 

For the research paper recently uploaded to preprint server medRxiv by Prof. Gwenaëlle Douaud, participants who had taken part in a previous brain study before the onset of the COVID-19 pandemic were reportedly invited back for a series of follow-up tests. The analysis revealed significant losses of grey matter surrounding the olfactory and gustatory systems in the parts that had been infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).

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