Genomics study shows why Covid spreads slower in Asia

All preventive measures including social distancing, contact tracing and quarantine have been key deterrents to the growth of the virus and could even facilitate India to keep community transmission at bay or reduce it. However, marked differences in different parts of the world were observed in terms of spread despite the measures taken.

COVID-19 is a virus-induced respiratory disease triggered by immunopathological mechanisms that cause excessive inflammation and leukocyte dysfunction which could result in acute respiratory distress syndrome (ARDS).

Neutrophils play a pivotal function in the eradication of bacteria with specific mechanisms to combat viruses. A recent study focused on the production of neutrophil extracellular traps (NETs) and its impact on severe lung diseases, such as COVID-19.

Now another study initiated based on biochemistry and genomics of the virus proved to have great potential in finding out the precise reason. Deficiency in a specific human protein now throws light as to why it has slower spread in Asia as opposed to US and Europe continents.

Genomics in Kalyani, West Bengal, have identified the root cause, which is based on biological elements. The scientists have depicted the simple mechanism of how higher levels of a human protein Neutrophil elastase assist the virus to enter the human body.

Nevertheless, this protein alone is not responsible for the spread but also another protein that generates from it called alpha-1 antitrypsin (AAT). AAT deficiency results in spike of neutrophil elastase in the cells, which in turn facilitates increased spread of the virus. This deficiency is learnt to be much higher in Europe and America cited from the journal, Infection, Genetics and Evolution.

The team of researchers spearheaded by Nidhan Biswas and Partha Majumder found that the incidence of the spread of the mutant virus -D614G- has been varying across the geographic regions.

The researchers say that, “in order to reach 50% relative the 614G subtype took significantly longer time in East Asia (5.5 months) compared to Europe (2.15 months) as well as North America (2.83) months.

Majumder added that the propaganda about the variations in Covid spread was made owing to the high temperature but the reason is biological and not physical or social attributes.

According to their data deduced from the study, AAT deficiency is lowest in East Asian countries — 8 per 000 individuals in Malaysia, 5.4 per 1,000 in South Korea, 2.5 in Singapore. On the other hand, 67.3 per 1,000 individuals in Spain had been identified.

But the team iterated that their research along with other social factors might describe the differential geographical or ethnic spread of the covid-19.