Coronavirus: India crisis

Travel links with India cut amid fears over mutant strain

Spike in new cases daily for past 6 days likely linked to B1617 variant

Migrant workers in a rush to return to their villages on Monday after the New Delhi authorities ordered a six-day lockdown to stem the pandemic spread. PHOTO: REUTERS
Policemen manning a roadblock in New Delhi yesterday. A six-day lockdown came into effect on Monday in a bid to curb a spike in Covid-19 cases that have stretched the Indian capital's health facilities. Migrant workers in a rush to return to their vi
Policemen manning a roadblock in New Delhi yesterday. A six-day lockdown came into effect on Monday in a bid to curb a spike in Covid-19 cases that have stretched the Indian capital's health facilities. Migrant workers in a rush to return to their villages on Monday after the New Delhi authorities ordered a six-day lockdown to stem the pandemic spread. PHOTO: REUTERS PHOTO: AGENCE FRANCE-PRESSE

More countries are snapping travel connections with India as it records a devastating spike in new coronavirus infections. The United States and Britain placed restrictions on Monday, with Washington advising people against heading to the Asian country even if they are fully vaccinated.

Hong Kong has banned flights from India for two weeks, beginning on Tuesday.

New Zealand has an ongoing suspension of entry of travellers from India, including its own citizens, until next Wednesday.

India has been reporting more than 200,000 new cases daily for six consecutive days since last Thursday, in a surge that has likely been fuelled by a potentially new virulent coronavirus variant.

The B1617 variant has been dubbed a "double mutant" because of two key mutations on the coronavirus' spike protein, which it uses to bind more effectively with cells and cause infection.

While the L452R mutation is known to expand viral transmission and reduce antibody efficacy, the E484Q mutation is said to give the virus increased cell-binding and immune-evasion properties.

The strain has been detected in at least 16 countries, including Singapore and Britain.

Dr Maria Van Kerkhove, the World Health Organisation technical lead officer on Covid-19, told reporters last week it is a "variant of interest" that the entity is tracking.

The role of this variant in the fresh spike in India has not been scientifically established but its prevalence has been creeping up in sequenced samples. A government statement on March 24 stated 15 per cent to 20 per cent of these had the B1617 variant, a rise compared with December.

"It is certainly the case that the proportion of double variant is gradually increasing. That is why it is a variant of concern, that it is spreading faster," Dr Rakesh Kumar Mishra, director of the Hyderabad-based Centre for Cellular and Molecular Biology, said .

He added that the strain is "probably not" a source of concern when it comes to beating vaccine-induced immunity or causing greater mortality. "But that needs to be studied properly," he said.

  • About the strain

  • • The B1617 strain has been dubbed a "double mutant" because of its two key mutations on the coronavirus' spike protein, which it uses to bind more effectively with cells and cause infection

    • Isolated samples of the strain were first sequenced late last year in India

    • Its prevalence has been increasing, with one recent study indicating that it accounted for as many as 61 per cent of 361 positive samples sequenced from Maharashtra

    • It has been reported in at least 16 countries, including Singapore and the United Kingdom

    • Indian scientists are currently studying it to determine if it can cause reinfection and beat vaccine-induced immunity

The centre is studying the strain to determine if it has the potential to cause reinfection or beat vaccine-induced immunity.

While results are not expected in another two weeks, the emergence of B1617 and its spread underscore the continuing threat of mutant variants emerging in India, which has the second-highest number of active cases after the US.

Dr Mishra said that while the strain does not seem to have "too many bad clinical features", such as high mortality, its capability to spread "more smartly" amid lax Covid-19-related behaviour could result in the emergence of another more lethal strain.

  • 16 Number of countries the B1617 variant, which carries several mutations, has been detected in, including Singapore.

In February, scientists at the National Centre for Disease Control and Institute of Genomics and Integrative Biology (IGIB) noted the presence of the L452R and E484Q mutations in the strain while analysing data from sequenced samples from Maharashtra.

They flagged it as a "variant of interest" as its prevalence began rising in Maharashtra, India's worst-hit state, and it showed up in other states. Dr Anurag Agrawal, IGIB's director, said B1617 "appears to have" spread fast like the B117 British strain that dominates positive "variants of concern" samples analysed so far in India.

He added that while B1617 is "probably less spreading" than the British variant, it may be more capable of beating immunity, noting that ongoing studies will offer more insights.

The second wave in India has been characterised by greater breathlessness among patients, leading to a greater need for medical oxygen. It is not known if this is an impact of the new strain.

The Indian Ministry of Health and Family Welfare acknowledged the double mutant strain's presence in March but added on April 16 that its higher transmissibility had not been established.

The strain has also not been termed a variant of concern by the government.

Isolated samples of the strain were sequenced late last year and there have been concerns that India is not sequencing enough positive samples to efficiently track strains and their spread.

As at last Thursday, 13,614 samples had been sequenced and 1,189 tested positive as variants of concern, comprising those from Britain (1,109), South Africa (79) and Brazil (one).

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A version of this article appeared in the print edition of The Straits Times on April 21, 2021, with the headline Travel links with India cut amid fears over mutant strain. Subscribe