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The value of vaccination and getting vaccinated remains very high and is crucial to overcoming this pandemic – Pic by Shehan Gunasekara
By Shashika Bandara and Neelika Malavige
The latest Omicron variant is currently a global concern. Emergence of new variants is partly due to the global vaccine inequity which has allowed the virus to infect many unvaccinated populations and mutate. The Omicron variant has been declared by the World Health Organization (WHO) as a Variant of Concern (VOC).
VOCs are variants that have been established to have increased transmissibility, significantly evade natural or vaccine induced immunity and (or) recognised as causing severe health outcomes. Although, Omicron was first detected in South Africa, recent reports indicate the virus being present in the European region prior to being present in South Africa, without any travel connections to the African continent.
Sri Lanka reported its first Omicron variant detection this past week. While the measurements of preparedness and mitigation is crucial to respond to the Omicron variant, it is vital that we avoid panic and uninformed hot takes on social media. The scientific understanding of the Omicron variant is rapidly evolving, and the current scientific understanding of the Omicron variant is limited. Acknowledging this will help us combat overtly certain misinformation.
This fact file aims to inform the public on the latest scientific understandings on the Omicron variant and how it applies to the Sri Lankan context.
What do we know about the Omicron variant?
From a public health perspective, transmissibility, ability to evade immune response, the severity of the health outcomes which is also connected to the impact on hospitalisations are important to inform next steps and policy measures.
Transmissibility: The data is inconclusive, with early data suggesting high transmissibility. However, more data is needed to provide a definitive analysis on transmissibility.
Given that the most comprehensive data is currently from South Africa, due to their dedicated and long-term surveillance, it is important to look at the data from South Africa. South Africa on 1 December 2021 has reported 8,561 cases, an increase of over 4,000 cases from reported 3,402 cases on 26 November 2021. South Africa’s National Institute for Communicable Diseases (NICD) has indicated the R value (the reproductive rate of the virus) is over 2 in Gauteng province. Generally, an R value over 1 means that the infections are increasing and below 1 means it is decreasing. However, this increase can be due to other factors and can also be due to relative heightened attention to Omicron in Gauteng. More data is needed from other countries, other regions of South Africa to definitively decide on transmissibility. Currently, WHO reports that as of 8 December, Omicron has been detected in over 57 countries. The WHO and other experts have warned countries to err on the side of caution, testing widely and stepping up genomic surveillance.
Immune escape potential: There is not enough data to conclude that Omicron evades the immune response. However, high-level of mutation on the variant, increasing amount of data from South Africa and laboratory data originating from the Pfizer-BioNTech laboratories, indicate the potential for immune evasion. While it is difficult to say if an Omicron specific vaccine will be needed, the importance of getting vaccinated is at an all-time high.
Early population level data in form of a pre-print of a study conducted in South Africa suggest that there are chances of the novel variant being able to evade the existing immune response increasing the chances of reinfection compared to delta and beta variants. However, a key factor of note is that in South Africa vaccination coverage is low and therefore many do not have immunity from vaccines – as immunity from prior infections is difficult gauge, more data will be needed to assess the reinfection capacity of Omicron. Therefore, it will be crucial to observe data of the Omicron variant from countries that have high vaccination rates.
Based on the mutations, although the virus has a high potential to evade vaccine-induced immunity or immunity following natural infection, due to mutations in the main neutralising antibody binding sites more data is required to find out the extent of such immune evasion.
Previously although vaccines have been less effective in preventing infection with variants that evade immunity (beta variant), vaccines have shown to still be effective in preventing hospitalisations, severe disease and death, which is important. Therefore, the value of vaccination and getting vaccinated remains very high and is crucial to overcoming this pandemic.
Severity of health outcomes: The early data suggests relatively milder health outcomes, again with a crucial caveat that there is not enough data to assess the severity. The increasing number of hospitalisations that is reported from South Africa does not necessarily mean severe health outcomes but indicates added caution due to how new this variant is and lack of clinical understanding. The WHO has a clinical data platform (https://www.who.int/teams/health-care-readiness-clinical-unit/covid-19/data-platform ) through which clinical data can be reported for analysis.
What does this mean for Sri Lanka?
As global evidence suggests, best preparedness efforts include increased surveillance, increasing vaccination coverage, providing booster doses as necessary, and ensuring public health measures to minimise transmission. Sri Lanka has made headway in many of these areas, especially aspects related to vaccination coverage. However, as the pandemic is an ongoing challenge, it is good to be aware of the moving targets that we need to achieve to keep communities safe.
One of the good news is that the public health measures remain the same, which include masking, distancing, limiting highly crowded gatherings, especially at indoor settings. While we are learning about the novel variant mutations, the understanding of the transmission mechanics of the virus has not changed. Therefore, it will be easier for us to look at previous public health guidance to help us as a country to be prepared.
From a public responsibility perspective, given the current living conditions challenges, it will be very hard to face another surge of cases. Therefore, minimising transmission will be key to avoid compounding the existing challenges related to living conditions in Sri Lanka. If possible, organisations and companies should be pro-active taking measures for transmission reduction.
Although, above measures seems basic and oft repeated, these measures are effective and therefore should be prioritised. If you are to take away one message from this article, let it be to increase your efforts to stay safe by masking, distancing, and avoiding crowded spaces where the risk of transmission of the virus can be high. It will be the kindest action you take for yourself and your community.