The effectiveness of vaccines against Omicron

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By EDUARDO CAMÍN*

More data are needed on vaccine efficacy, particularly against hospitalization, severe illness, and death.

Despite the efforts of the WHO (World Health Organization), reality shows that the richest countries have bought enough doses to vaccinate their entire population almost three times more than necessary, in a world where no one should be left without a vaccine because of the country you live in or how much money you have in your pocket.

The Omicron variant is spreading rapidly around the world, with experts emphasizing and insisting that this is unlikely to be the last version of the virus we will see circulating.

All pharmaceutical companies and research institutions working on COVID-19 vaccines and drugs should share their formulas, knowledge and the intellectual property behind the products so that doses can be produced in sufficient quantities, safe and effective for all. . Governments also have a responsibility to demand that the pharmaceutical industry put people's lives before their own profits. But the harsh reality is very different.

In September 2021, WHO created the Technical Advisory Group on Vaccine Composition against COVID-19 (TAG-CO-VAC, for its acronym in English). This multidisciplinary group is made up of 18 specialists and has the task of analyzing and evaluating the implications of the new variants on public health, their reaction to anti-covid-19 vaccines, and making recommendations on the composition of these vaccines.

The work of this group is complemented by the Technical Advisory Group on Virus Evolution (TAG-VE), the Strategic Advisory Group of Experts on Immunization (SAGE), the Working Group on Vaccines and the WHO Epidemic Research and Development Plan .

In the current context, regarding the circulation of the Omicron variant, the TAG-CO-VAC asked for greater access to vaccines that already exist in all countries of the world, with schemes that already include booster doses, in the hope that this acceleration of vaccination in poorer countries may reduce the chance of new variants emerging.

TAG-CO-VAC experts are considering strain composition of COVID-19 vaccines and encourage vaccine developers to collect small-scale data on the breadth and magnitude of the immune response to monovalent and multivalent vaccines against different variants. These data would be analyzed in a broader decision-making framework on vaccine composition.

Since its appearance, the SARS-CoV-2 virus has been evolving and producing new strains. Among those officially registered by the WHO, the Alpha, Beta, Gamma, Delta and Omicron variants are the best known, because they are the most contagious and/or because of their ability to develop a more serious disease, or because they are more resistant to vaccines.

Since the WHO identified the Omicron variant on November 26, 2021, the TAG-CO-VAC has been meeting regularly to review the evidence on its characteristics. The group is developing a framework to review the evidence on emerging variants, taking into account the criteria that would trigger a recommendation to change the composition of anti-COVID-19 vaccines. The aim is for the group to advise WHO on necessary updates to vaccine compositions.

This framework considers global spread and transmissibility, clinical severity, genetic, antigenic, and phenotypic characteristics of the variants, including waning ability to immunize, and assessments of vaccine efficacy.

 

Global public health targets for anti-COVID-19 vaccines

With vaccines available, the current focus remains the same: that vaccines are effective in preventing the most severe version of the disease, reducing deaths or even eliminating deaths and hospitalizations, and allowing the normalization of the pace of work of health systems. Vaccines included on the WHO Emergency Use List provide a high level of protection against serious illness and death caused by new variants.

For the Omicron variant, the mutational profile and preliminary data indicate that vaccine efficacy against mild symptomatic disease is reduced. However, it is more likely that protection against the severe version of the disease will be preserved. However, more data are needed on vaccine efficacy, particularly against hospitalization, severe illness and death, including for each vaccine platform and for various dosing regimens and vaccine products.

In alignment with SAGE and its Vaccine Working Group, TAG-CO-VAC supports widespread and urgent access to current vaccines for priority populations around the world to provide protection against serious illness and death. In the long term, the goal is to mitigate the emergence and impact of new variants, in addition to reducing the infection burden.

In practical terms, this means that while some countries may recommend vaccine booster doses, the immediate priority for the world is accelerating access to primary immunization, particularly for groups most at risk of developing serious disease.

With short- and medium-term vaccine supplies available, the need for equity in access to vaccines across countries to meet global public health goals and programmatic considerations, including demand for vaccines and virus evolution, is A vaccination strategy based on repeated booster doses of the original vaccine composition is unlikely to be appropriate or sustainable.

 

Changes in the composition of current and future vaccines

TAG-CO-VAC believes that vaccines that have a high impact on preventing infection and transmission, as well as preventing serious illness and death, are needed and must be developed. Until these vaccines are available, and as the SARS-CoV-2 virus evolves, the composition of current anti-covid-19 vaccines will need to be updated to ensure that they continue to provide WHO recommended levels of protection, even against infections. caused by Omicron and future variants.

WHO's aim is to ensure that vaccines continue to meet the criteria set out in the product profile, as well as protection against serious disease to improve vaccine-induced safety. For this, anti-covid-19 vaccines must: be based on strains that are genetically and antigenically close to the circulating variant(s) of SARS-CoV-2; be more effective in protecting against serious illness and death from the infection, thereby reducing community transmission and the need for rigorous and comprehensive public health and social measures; induce broad, strong and long-lasting immune responses to reduce the need for successive booster doses.

Under this approach, there are many options to consider. One is that of a monovalent vaccine that induces an immune response against the predominant circulating variant(s), although this option is challenged by the rapid emergence of SARS-CoV-2 variants and the time needed to develop a modified or new vaccine. Another option is that of a multivalent vaccine containing antigens from different strains of SARS-CoV-2. The third alternative is a pan-sars-CoV-2 vaccine – this is the most sustainable long-term option, and one that would be effectively variant-proof.

Meanwhile, TAG-CO-VAC encourages vaccine manufacturers to generate and provide data on the performance of current and Omicron-specific vaccines, including the amplitude, magnitude and durability of immune responses to variants.

These data will be considered in the context of the aforementioned framework to inform TAG-CO-VAC decisions when vaccine composition changes are required. It would be important for vaccine manufacturers to take short-term steps to develop and test vaccines with prevalent circulating variants, and to share this data with TAG-CO-VAC and other relevant WHO expert committees. Vaccine manufacturers are also encouraged to provide this data for any new, widely reactive SARS-CoV-2 vaccines that are developed.

TAG-CO-VAC will continue to evaluate the evidence on predominant circulating variants with regard to excretion/transmissibility properties, clinical severity (virulence), genetic, antigenic, and phenotypic characteristics of these new strains, including their ability to resist immunity generated by vaccines, in addition to evaluations of the effectiveness and impact of these vaccines and the information provided by the manufacturers. TAG-CO-VAC will advise WHO on the composition of the vaccine strain that can be developed as a monovalent vaccine, with the predominant circulating variant or a multivalent vaccine derived from different variants.

WHO urged the scientific community to rise to the challenge of ensuring the production of the best vaccines as quickly as possible, which requires continuous information sharing and collaboration between WHO and its expert groups, the TAG-CO-VAC, regulatory authorities in each country and vaccine manufacturers. The entity is committed to facilitating this process. Meanwhile, vaccine owners only care about their interests.

 

The contrast between theory and practice: a tragic dimension

On December 23, 2021, India sent a letter to the President of the General Council of the WTO (World Trade Organization), requesting the holding of a virtual ministerial meeting on the issue of dealing with the pandemic, including the proposal to waive certain provisions of the TRIPS Agreement for vaccines, therapies and diagnostics related to COVID-19.

On the same day, Ambassador Dacio Castillo, President of the General Council, distributed a letter to all delegations, indicating that he would “conduct consultations and convene an open informal meeting of the General Council” on the matter during the first week of January. In her remarks, the WTO director-general, Ngozi Okonjo-Iweala, called for urgent action to reach a comprehensive opinion from the entity on facing the pandemic. “More than two years have passed since the beginning of the health crisis. The emergence of the Omicron variant forced us to postpone our 12th Ministerial Conference and reminded us of the risks of allowing large parts of the world to remain unvaccinated.” “We at the WTO need to urgently step up our part to reach a multilateral outcome on intellectual property and other issues, in order to contribute fully to global efforts to combat COVID-19,” she added.

The vaccine backlog is actively undermining global efforts to ensure that every person, in every country in the world, can be protected from Covid 19. Rich countries have clear human rights obligations, not only must they stop actions that hamper access to vaccines in other parts of the world, but they also need to cooperate and provide assistance to countries that need them.

By buying up the vast majority of the world's supply of vaccines, rich countries are flouting their human rights obligations. The current system, in which pharmaceutical companies use government resources for research, maintain exclusive rights and safeguard the technology, to increase the profits of large corporations. This policy demonstrates a myopia that can cost many lives.

The speeches of the rulers of the world and all the big media talk all the time about the coronavirus and how to deal with it. But it is fundamental to identify, in the first place, that we are in the hands of a sinister bourgeois political leadership, commanded by a nucleus of industrialized countries, in association with financial corporations. The everyday logic of the capitalist system and its neoliberal economies manifests a total disregard for human life, as it is ordered exclusively by profits.

It must be said loud and clear: the issue of access to the vaccine is against the backdrop of the brutal trade war waged by the main capitalist powers on the planet, to gain an advantage, a trade race and an irrational dispute between powers. A scenario that, unfortunately, takes on tragic dimensions for the vast majority of people.

*Eduardo Camin is a journalist and analyst associated with the Latin American Center for Strategic Analysis (CLAE).

Translation: Victor Farinelli to the portal Major Card.

Originally published in estrategia.la