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The 66-year-old man, who has received both vaccine doses, travelled from South Africa on November 20 with a negative Covid report. He tested positive on arrival and was asymptomatic, following which he was told to self-isolate. A week later (with a negative Covid report from a private lab) he flew to Dubai. Samples from 24 primary and 240 secondary contacts have returned negative test results.
The second patient is a health worker from Bengaluru who developed symptoms (fever and body ache) on November 21. He tested positive the following day and was admitted to hospital; his sample was sent for genome sequencing on the same day. However, three days later he was discharged. His vaccination status is unclear at this time.
Worryingly, three primary and two secondary contacts tested positive between November 22 and 25. All five have been isolated but it is not known, so far, if they have the Omicron strain. Overall 13 primary and 205 secondary contacts were tested.
As it confirmed the presence of the Omicron strain in India, the government underlined the mantra "awareness is absolutely essential". It highlighted a WHO advisory that says Covid-appropriate behavior - use of face masks, avoiding crowded places, practicing social distance and frequently sanitising hands - remain effective in guarding against infection by any variant, including Omicron.
International airports across India began intensive screening and testing of all arrivals from yesterday morning. In line with central guidelines, all passengers arriving from 'at risk' countries (this includes European nations and South Africa, where the Omicron strain was first detected) have to take RT-PCR tests on arrival. The test result has to be negative in order to leave the airport.
Passengers from nations outside the 'at risk' list are being tested on a random sampling basis (approximately two per cent of each planeload). They can leave the airport before the test result is declared. All international arrivals, though, have to fill out self-declaration forms to allow the government to track them down in case they (or a contact) test positive.
This morning Maharashtra - which announced a stricter set of rules and invited the centre's displeasure in doing so - said four Covid cases had been reported among international passengers who landed in Mumbai before the Omicron travel rules. Two were from London, another from Mauritius and the fourth from South Africa.
On Wednesday Maharashtra and Delhi announced six Covid cases each among international arrivals, with Chandigarh reporting two more cases (including one close contact). All these cases have been placed in isolation and their samples are being tested to confirm the infecting strain.
The Omicron strain - designated a 'variant of concern' by the WHO - is believed to have 50+ mutations, including over 30 on the spike protein, which make it significantly more infectious than the Delta variant that is currently dominant worldwide; it constitutes over 60 per cent of all Covid cases in India.
Researchers are still checking if Omicron is more lethal and if current vaccines offer protection. Pfizer has begun working on a new vaccine and a drug by GlaxoSmithKline seems effective. Adar Poonawalla, CEO of Serum Institute, which produces the AstraZeneca vaccine sold in India as Covishield, told NDTV a new version of its jab could be developed as well, depending on results of ongoing studies.
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