The results were observed among individuals previously vaccinated with either Vaxzevria or an mRNA vaccine.
SII had partnered with the developer of Covishield, AstraZeneca, for the supply of the vaccine to the Indian government, which had in January this year granted emergency use authorisation.
Countries such as Japan, South Korea, China and Thailand quickly reinstated entry and quarantine restrictions in recent weeks after relaxing them in the fall.
According to Our World in Data, a website run by the University of Oxford, the UK has 1.7 daily deaths from COVID per million people.
The study found that antibody levels against Omicron after the booster shot were higher than antibodies in people who had been infected with and recovered naturally from Covid-19.
Researchers analysed data for two million people in Scotland and 42 million people in Brazil who had been vaccinated with the AstraZeneca vaccine.
Evusheld has also received authorisations in other countries, the pharma major said, adding that it is now working with regulators on applications for the use of Evusheld in treating Covid.
Evusheld is a long-acting antibody combination for the prevention of COVID-19.
The Foreign Ministry said the AstraZeneca vaccines would be transferred in the coming weeks, a decision that was part of Israel's strengthening ties with the African countries.
Gilbert, who was made a Dame by Queen Elizabeth II for her pivotal role in developing the Oxford/AstraZeneca vaccine, said there needed to be more funding for pandemic preparedness.
Speaking about the Omicron variant of the novel coronavirus, she said its spike protein contained mutations known to increase the transmissibility of the virus.
The 19,000 square-meter (more than 200,000 square-foot) complex will house more than 2,200 research scientists.
The Oxford/AstraZeneca vaccine, which is also being manufactured by the Serum Institute of India (SII) as part of an agreement, has until now been sold on a not-for-profit basis.
The new rules allow air travel from previously restricted countries as long as the traveller has proof of being jabbed with any WHO-recognized vaccine and a negative COVID-19 test.
Switzerland has cleared the BioNTech-Pfizer, Moderna and Johnson & Johnson vaccines for use.