Dec 29: What we know about the Omicron variant so far
On Wednesday, Delhi logged 923 new Covid-19 cases, its highest in a single-day in several months.
The Omicron variant may have reached community transmission in Delhi. Officials shared data showing one of the main genome sequencing hospitals – a genome analysis determines the variant of a Sars-CoV-2 sample – in the Capital found 53% of the samples to be of the Omicron variant. People aware of the matter said these samples were taken as part of “sentinel surveillance”, which means they are from labs in different parts of the city where people have tested positive.
The findings explain what case numbers say. From reporting around 100 cases a day a week ago, the Capital logged 923 cases in a single day on Wednesday. The proportion of tests turning positive – 1.29% -- rose to its highest in 212 days.
This was expected. And so far, Delhi’s experience appears to be consistent with the mild but rapid spread seen in the early phases in South Africa and the UK, the first hot spots of the Omicron variant. According to the Delhi government’s daily bulletin, of the 2,191 active cases in the city, only 55 are on oxygen support with the remaining being asymptomatic or mildly symptomatic.
Preparing testing for the surge
The Omicron surge will soon begin to pose a problem for the city’s testing infrastructure if the current protocols on when to get a test continue. Even if Omicron cases are largely mild, the testing system needs to be protected to allow for people who need it -- those with moderate or severe symptoms -- to be able to take one.
Two countries illustrate why the threat that the variant will exhaust testing capacity is significant: Denamrk and the UK. In Denmark, the third country where Omicron took hold after South Africa and the UK, testing hit a ceiling after a peak positivity rate of 47%. In UK, too, there are shortages of RT-PCR test appointments as well as antigen test kits.
In per capita terms, both have a significant outbreak. On average, Denmark reported 2,000 new cases per million people over the last week while for the UK, this number was 1,411.
India, at its peak in May, reported 280 cases per million.
Faced with a similar Omicron surge as the others, India’s testing capacity will not be able to keep up. This is where UK’s experience offers an important lesson: rapid test kits may hold the key.
People in the UK are allowed a free quota of rapid test kits (known as lateral flow devices – or LFD) that they can take at home. This has allowed even people with no symptoms to isolate even if confirmatory RT-PCR tests have not been available. The UK’s official guidance was also updated recently to advise that people can end their isolation at seven days if they have two negative tests on days 6 and 7.
Naturally, this will not be possible for a populous and resource-restricted country like India to replicate. But what India could do is ease its protocols making it mandatory for official testing to maintain a 40:60 ratio between rapid and PCR tests. Though rapid tests are less accurate than the gold standard RT-PCR, the ease with which they can be distributed lends itself to be an easy testing tool for offices and residential blocks. Each infection they catch will help a person make the choice on isolating and not putting someone else at risk in the absence of symptoms, instead of creating a waiting list of PCR tests.