4 South Africa variant cases found, 1 with strain from Brazil
Four people who flew into India last month were infected with the South African variant of the Sars-CoV-2 virus, and another traveller was found infected with the Brazilian variant, the Union health ministry said on Tuesday, announcing the detection of the two mutations that scientists fear can make coronavirus vaccines less effective and trigger reinfections among people.
Authorities have carried out contact tracing for the five people, and no other person is found to have contracted the new variants till now, Union health secretary Rajesh Bhushan said at the weekly government briefing on Covid-19 in the Capital. People returning from these countries will now be tested more aggressively, he added.
“There are no direct flights from South Africa or Brazil, so the health ministry and the civil aviation ministry are in touch on the steps to be taken on the matter,” Bhushan said, while refusing to give details about which airport the five people arrived at or their location at present in order to protect their privacy.
India now has all three of the coronavirus variants that are a global concern -- B.1.1.7, first discovered in the UK; B.1.351, which is now dominant in South Africa; and P.1, which has spread in Brazil. All three have a unique collection of mutations, two of which -- N501Y and E484K -- seem to make it spread more readily or cheat vaccine-immunity triggered by the virus predominant in the world. The UK variant carries the N501Y mutation, the Brazilian variant has the E484K mutation, and the South African variant has both.
Bhushan indicated that genomic tests of all positive cases among people who arrive from Brazil and South Africa are likely to be carried out. “We got genome sequencing done of all those who were found positive among those tested for the UK variant. This strategy worked significantly well, and most likely the same strategy we will apply for flights coming from South Africa and Brazil,” he said.
But, he added, passengers from South Africa and Brazil do not take direct flights. “The traffic is largely routed from other sectors; for example, the Gulf sector. So, to have measures that can be put in place for passengers coming from these two countries, the Union health and civil aviation ministries are in constant touch and should come up with a solution soon that will be made public,” he said.
The South African strains were found among two people who returned from the country as well as one traveller each from Angola and Tanzania.
“All travellers and contacts have been tested and quarantined, and ICMR-National Institute of Virology is attempting to isolate and culture the South Africa variant strain from the samples of these four individuals,” said Dr Balram Bhargava, director general, Indian Council of Medical Research (ICMR).
The South African and Brazil variants are different from the UK variant because the Brazilian and South African variants have the capacity to easily enter the lungs, Bhargava said.
Last year, the Union government created the Indian Sars-Cov-2 Genomic Consortium (INSACOG) of 10 laboratories based at the National Centre for Disease Control (NCDC), Union ministry of health and family welfare, as part of a surveillance mechanism for early detection of variants of concern.
“For the UK variant, we have found 187 such variants. We were able to isolate the virus and culture the strain and have also tested the efficacy of the Covid-19 vaccine. Neutralising potential with the UK variant is there with the vaccine that is in use in India,” Bhargava added.
Such experiments in South Africa have showed that the Oxford-AstraZeneca vaccine’s efficacy dropped to an insignificant 22% against the B.1.351 variant. The country dropped its plan last week to use the vaccine, which is also being used in India as Covishield, and has decided to offer doses to the African Union, where the variant has not reached. Vaccine trials carried out by Johnson & Johnson-Janssen and Novavax too showed a significant drop in efficacy due to the variant.
Similar implications could also hold for people who were previously infected. World Health Organization chief scientist Soumya Swaminathan said on February 14 that WHO had received new reports of reinfection, including some from South Africa where people who had Covid-19 were infected again.
The coronavirus outbreak has waned dramatically in India and over the past week, the country recorded around 93 deaths a day -- a level not seen since early May. The decrease has raised fears that people might become complacent, and that variants such as the three of global concern could take hold, wiping out population immunity and triggering a resurgence.
According to ICMR, experiments to assess vaccine effectiveness against this strain are currently underway. “The significance of a mutation will depend on where the mutation has happened, as mutations in RNA viruses happen all the time. It will be significant if the mutations help the virus to attach to the cell easily as then it will impact the disease spread,” said Dr Shobha Broor, former head, microbiology department, All India Institute of Medical Sciences, Delhi.