COVID-19: omicron is a reminder of the ongoing threat posed by SARS-Cov-2

The appearance of variants such as omicron “Is a reminder of the ongoing threat” posed by SARS-CoV-2 and the importance of vaccines that, with the third dose, they can restore their effectiveness to more than 90%, against severe disease, according to an analysis published by Science.

Cambridge University microbiologist Ravindra Gupta and Scripps Research Translational Institute researcher Eric Topol reviewed recent studies on infections after vaccination and on the efficacy of booster doses in protecting against variants, especially delta.

The authors recall the high levels of protection of messenger RNA vaccines, such as Pfizer and Moderna, against the COVID-19 symptomatic, but that decreases with time, especially in the elderly and immunosuppressed.

Studies indicate that time was a key factor in the wear and tear of vaccine efficacy, and the loss of protection “was probably amplified by the increased prevalence of the delta variant,” the scientists write.

Immunological studies of the response to booster injections given six months after complete vaccination have shown “uniformly the induction of very high amounts of neutralizing antibodies.”

The authors cite a study conducted in Israel, where more than 1.1 million people over the age of 60 were boosted with an mRNA vaccine and more than 90% effective against severe COVID-19 was restored.

While boosters are important and may remain so for a time, non-pharmaceutical interventions, such as mask use and social distancing, not only help reduce COVID-19 cases, but also limit the opportunity for variants to emerge. that can evade immunity.

New variants can evolve from delta, be totally different, and even “could be recombinant variants due to mixed infections within individual hosts.”

Both experts also refer to the variant B.1.1.529 (omicron), which is gaining ground throughout the world and which presents multiple mutations in the spicule protein (S), about which they say that “it is a reminder of the ongoing threat posed by SARS-CoV-2 ″.

Continued transmission of the coronavirus in heavily vaccinated populations “underscores the need to scale-up vaccination across all age groups, while maintaining non-pharmacological interventions, such as the use of masks,” write Gupta and Topol.

Additionally, they advocate intranasal vaccine research as a means of preventing infection or exploring the potential of antiviral drugs.