“BOOSTER” OF UNIVERSAL CONCERN

A SARS-CoV-2 variant of Pango lineage B.1.1.529, with a high number of S-gene mutations compared to the original virus, has been designated a variant of concern (VOC) and assigned the name Omicron, a word derived from the Greek alphabet, by the World Health Organization (WHO).

The Omicron variant is the most divergent variant that has been detected in significant numbers during the pandemic so far, which raises concerns that it may be associated with increased transmissibility, considerable reduction in vaccine effectiveness, and increased risk for reinfections.

This circumstance with the new variant has triggered the discussion about the rationale for third and subsequent dose administration of COVID vaccines to everyone ages 18 and above.

The academia, researchers, governments, and industry responded to the COVID19 pandemic with a sense of urgency and at a speed unknown in the history of humanity to develop safe and effective vaccines against SARS-CoV-2. It remains our best instrument to contain the COVID-19 pandemic. However, emerging SARS-CoV-2 viral strains and aggressive variants like OMICRON and the possibility of fading immunity following vaccination lead us to unchartered territory. There is an acute need to investigate the necessity for additional immunization or so-called booster doses.

CDC Advisory Committee on Immunization Practices recommended a booster shot of COVID-19 vaccines in certain populations and recommended a booster dose for those in high-risk occupational and institutional settings. Based on this recommendation, the Food and Drug Administration (FDA), USA, authorized Pfizer-BioNTech, Moderna, and J&J vaccines for an additional third dose or booster dose. Some experts believe it as an “important step forward as we work to stay ahead of the virus and keep populations safe”. Dr. Walensky, CDC Director stated, “I believe we can best serve the nation’s public health needs by providing booster doses for the elderly, those in long-term care facilities, people with underlying medical conditions, and for adults at high risk of disease from occupational and institutional exposures to COVID-19”.

Though booster was initially approved for vulnerable populations, these vaccines are approved for wider use as a booster in recent development. The CDC statement says: “Everyone Ages 18 and Older Can Get a Booster Shot”.

These decisions and actions by developed countries who are piling up the vaccine doses and allowing the booster doses with limited scientific evidence of their rationality “put further pressure on disregarded human life in lower-income countries that already have minimal access to COVID-19 vaccines”.

The questions of vaccine equity and ethics raise when significant populations in low medium countries have no access to even first and second doses. It's high time WHO, public health professionals, governments, and stakeholders revisit the booster doses issue, keeping in mind potential waning immunity, new variants with high immune escape, and prioritizing vulnerable populations everywhere, including those living in lower-income countries.

Inequitable administration of COVID-19 vaccine boosters based on superficial and weak evidence of antibody levels alone will further worsen vaccine inequity and is an unacceptable situation from both ethical and healthcare standpoints. A decline in titers of binding and neutralizing antibodies overtime is expected after vaccination. Studies have shown COVID-19 vaccines in addition to humoral shall have the potential to provide sustainable cell-mediated immunity too. Hence, further research and strong evidence are needed to determine the protection correlate and threshold to address the need for a third vaccine dose.

Till then the global community should focus on vaccinating a significant part of the world population everywhere including in low medium-income countries with at least two doses. Simultaneously, researchers, vaccine developers, and manufacturers should tweak the current vaccines to effectively deal with ever-increasing and aggressive new variants of concern.

Our efforts to control the COVID-19 pandemic may be futile if we leave the majority of populations in low medium-income countries out of vaccination programs. The WHO chief Tedros Adhanom Ghebreyesus said, “It makes no sense to give boosters to healthy adults or to vaccinate children, when health workers, older people, and other high-risk groups around the world are still waiting for their first dose”. It’s time for empathy, focus on efforts that truly matter to contain the pandemic, true leadership, not empty promises, misplaced priorities, and greed to benefit from the situation.

Hope the right messaging to the public that COVID appropriate behavior focused on 3Ws: Wash your hands, Wear your mask, Watch your distance and 2Vs: Ventilation, Vaccination, shall help us to significantly reduce the risk of transmission, infection, and impact of emerging variants.