The delta variant of the coronavirus has been the dominant strain in many countries, and believed to be the driving force behind the second wave of Covid-19 pandemic. The variant has been causing a spike in the number of cases in South Africa and the United Kingdom, scuttling the Boris Johnson government’s plan to reopen the country.
The delta variant, which has further mutated into the delta plus, has 60% higher transmissibility rate than the original aplha variant. which was first detected in United Kingdom’s Kent. Delta was first detected in India.
The estimates for doubling rate (time taken for the number of infections to double) of infection for the Delta is also relatively high, with doubling time ranging from 4.5 days to 11.5 days.
A detailed study conducted by Scottish researchers last month showed that the delta variant doubles the risk of hospitalisation compared with the previously dominant variant in the UK.
The study was published in leading medical journal The Lancet. It said that those with comorbidities and old age are at increased risk of contracting the delta variant. Public Health England (PHE) also described the vulnerable group, claiming that the young and unvaccinated are at increased risk of getting infected with the strain.
The Scottish study looked at 19,543 community cases and 377 hospitalisations among 5.4 million people in Scotland, 7,723 cases and 134 hospitalisations of which were found to have the delta variant.
They also said that two doses of vaccine provide much better protection than one dose against the delta variant.
The PHE, meanwhile, said that Covid-19 vaccines made by Pfizer and AstraZeneca offer high protection of more than 90% against hospitalisation from the delta variant of coronavirus. Researchers at Pune’s Indian Council of Medical Research-National Institute of Virology (ICMR-NIV) have claimed that Bharat Biotech’s Covaxin is also effective in neutralising the delta and beta variants of Sars-CoV-2.
However, there are some studies which say that delta variant can infect vaccinated people, though the infection does not turn severe.
