Omicron: When mild is deadly

Citizens get vaccine shots at BYL Nair Hospital on Tuesday. Pic/Ashish Raje

With UK reporting the first death due to Omicron variant on Monday, health experts are concerned about a latest projection of time and death curve from the London School of Tropical Hygiene and Medicine. The new variant is allegedly "fast and mild" and the projection shows how such variants often kill and harm more than a Covid-19 variant that is slower and more severe (such as Delta).

Though the study is a hypothetical projection, experts say it cannot be taken lightly as the variant has spread to almost 63 countries so far. Health experts say it is safe to be on a defensive mode instead of wishful speculation. Dr Wiqar Shaikh, Professor of Medicine, Grant Medical College and Sir J J Group of Hospitals, recalled that in an earlier mid-day article ‘Pharma Cos must adapt existing vaccines as fast as possible', published on November 28, he had said that Omicron has a higher transmissibility as compared to the earlier variants of Covid-19 and therefore could spread faster.

Dr Ketan Vagholkar, Professor of Surgery at DY Patil Medical College

The London School of Tropical Hygiene and Medicine has warned that as per the projections, there could be approximately 75,000 Omicron-related deaths in the UK by April 2022. Dr Shaikh said that till date, Omicron, which was first reported in South Africa, has spread to 63 countries. Dr Shaikh quoted several studies and tweets by Adam Kucharski in which Kucharski analysed and discussed the transmissibility of the SARS-CoV-2 virus and recently of Omicron. Dr Shaikh said that Kucharski has concluded that a two times more transmissible and 10 times less lethal variant could lead to more deaths when compared to a more lethal variant. The Omicron variant, as has been reported since its discovery, fits into a mild variant with more transmissibility and therefore is expected to lead to more hospitalisations and more deaths. He warned that the information that Omicron is a milder variant could lead to complacency in the general population, leading to disastrous results.

‘Omicron transmission faster than Delta variant'

"While the debate is heating up all over the world on damaging effects of Omicron, the worrisome message going out from health experts to the general public is that omicron infected persons have milder disease, leading to fewer hospitalisations, although Omicron transmission through air and body touch is 2-10 times faster than the Delta variant. That message is taken by the general public as reassuring, leading to a false sense of security. Instead, Italian demographer-researcher Dr Gosia Gaspero, who has been using mathematical models for disease outcomes for several years, stated a Covid variant that transmits faster, even if much milder, could lead to many more deaths," said Dr Subhash Hira, Professor of Global Health at the University of Washington-Seattle and an invited expert to WHO-Geneva Covid review groups.

A health worker collects a swab sample of a passenger at Dadar station. Pic/Ashish Raje

"The chart [see pic] compares clinical disease severity versus fatality numbers in 5-day blocks for four variants of Covid-19, namely baseline wild SARS-CoV-2 virus that began December 2019 was slow and caused severe disease (black line); Delta variant that emerged in April-May 2020 was slow and caused severe disease (black line); Omicron that is fast and caused mild disease (green curve) emerged in November 2021; and the next likely variant that will emerge will be fast but may present with ‘normal' health parameters (red curve). It means that a ‘fast spreader and mild-disease virus' such as the Omicron will often kill and harm a large number of people (green curve) than a virus that is slower but more severe disease producing virus (black curve). Worse still that may come at some point could be ‘fast spreader but with normal health' that may kill and harm a large number of people (red curve)," explained Dr Hira.

‘Defensive mode'

"Omicron has caused a global panic after the WHO described it as a ‘variant of concern'. Though its exact pathogenicity is yet to be ascertained, various hypotheses have been put forth on the transmissibility and severity of disease. One should not underestimate the pathogenicity of Omicron. It is safe to hedge on a defensive mode instead of wishful speculation. Completion of vaccination and meticulous use of the mask at all times continues to be the mainstay of prevention," said Dr Ketan Vagholkar, Professor of Surgery at DY Patil Medical College.

The chart by Italian demographer-researcher Dr Gosia Gaspero on time and death curve of the different variants

Dr Santosh Bansode, Head of the department, Emergency Medicine, Wockhardt hospitals, Mumbai Central, said, "A new hypothetical study showed that variant which is fast in spreading and even though mild can cause many more deaths. Simple logic is that when any variant spreads fast, the number of people infected will be more and more people with comorbidities will also get infected. As we know, people with comorbidities have a larger risk of getting serious symptoms and mortality. So definitely if we fail to stop Omicron, there's a high chance that we will face a huge problem." He added, "Omicron is a new threat and we need to take all measures to stop its spread. There is no escape from taking precautions till we get zero Covid cases in our country." "New variants may emerge from time to time so we must continue our research in the development of vaccines which can protect us from all variants. Strict Covid protocols should be followed," he added.