By Dr Amit Gupta
It’s back. Not that it had ever gone away, but the old Delta variant cases are down, masks have slipped, it is wedding season, and life is resuming a semblance of normality. Sadly, Omicron is likely to change all that.
Omicron spreads some four times as fast as the Delta variant. In the UK, it already accounts for nearly 40% of all cases and is predicted to replace the Delta variant by Christmas. The doubling rate is now down to two days and on Wednesday, the UK recorded 78,000 cases, making it the highest-ever number of positive cases since the pandemic began.
There are only 57 cases of Omicron reported in India. This is certainly an underestimate. Firstly, genetic screening for the variant is limited. The National Institute of Virology receives close to 100 samples per day. Compare that to nearly half the UK laboratories being able to detect the variant. Secondly, the screening is still being targeted at overseas arrivals. Local transmission has already occurred. Finally, disease presentation is different which makes it less likely for people to be tested. More people are reporting symptoms suggestive of common cold, and there are fewer reports of the classic symptoms such as loss of smell and high fever.
News from South Africa seems to suggest that the Omicron variant may be ‘mild’ in its impact – the case fatality rate is 0.5% compared to 3% with the Delta variant. Balance that against the sheer ferocity of the spread of the virus and the data would appear less optimistic. Put simply, 0.5% can translate into huge numbers if the virus rips through cities. In the UK, with its record number of positive cases, hospitalisations are already up by 10% week-on-week and up to 30% in London. Death numbers lag by a few weeks and there may be bleaker news in the new year. The population of South Africa and the UK is a mere quarter of that of Uttar Pradesh. It is not difficult to see how an allegedly less lethal but much more infectious variant can overwhelm the healthcare system and lead to a high number of deaths.
The ‘mild disease’ tag remains unproven. Even if it were true, it is not clear whether this is down to a ‘weak’ virus or a virus weakened by immunity (vaccine or infection). Until we know, we should presume the latter. The WHO makes this point strongly. South Africa had its third wave recently (July to November) which may explain why protective antibody levels may be higher and may be compensating against the relatively low levels of vaccination (26%) coverage.
Beyond the usual advice on masking, hand washing, etc., our best defence lies in increasing our immunity. Data clearly shows that protection via two doses of the vaccine wanes beyond six months. A third dose may not cut transmission as much, but it does restore protection against serious disease. It is no surprise that the UK and the EU are racing to give third doses or booster shots to their populations; all adults who are beyond three months of the second dose are being offered boosters. There are huge queues at vaccination centres and nearly 1 million vaccines are being injected per day.
India is vaccinating at nearly 8 million vaccines a day and has a mature production-and-supply chain. Impressive as it sounds, it actually translates to 38% of the population having received two doses. The elderly and healthcare workers were prioritised in the vaccine drive. Most of them are now post six months of their second dose and are vulnerable to re-infection with Omicron. This makes a strong case for introducing targeted boosters for this population (if not all adults). This should be achievable without disrupting the ongoing effort to vaccinate all with two doses.
We cannot afford to presume that we are dealing with a weak virus. Our best hope is to bolster our defences. The winter, upcoming elections in several state, and the general lowering of guard in the population may create a perfect storm.
Boosters should be offered now.
Dr. Amit Gupta is the Clinical Director for newborn services at Oxford.