Omicron and other variants of concern identified in the Americas

3 Dec 2021
COVID-19 variants

Washington, Dec. 3, 2021 (PAHO)—All five Variants of Concern of the SARS-COV-2 virus have been identified in the Americas, including Omicron, which is now in three countries, according to an Epidemiological Update from the Pan American Health Organization (PAHO).

The most frequently appearing variant is Delta, and since it was first reported in July 2020, 181 countries worldwide – including 54 countries and territories in the Americas – have reported its detection, PAHO’s Update notes.

The Omicron variant, designated as a Variant of Concern by the World Health Organization last week, has been reported in at least 25 countries worldwide, but “it is not yet clear whether VOC Omicron is more easily transmitted from person-to-person compared to other variants,” or if it causes more severe disease.

“Understanding the level of severity of VOC Omicron could take several weeks. All SARS-CoV-2 variants, including the globally dominant VOC Delta, can cause serious illness or death, particularly for the most vulnerable people; therefore, prevention is always paramount,” PAHO’s Epidemiological Update says.

The other variants now circulating, predominantly Delta but also Alpha, Beta, and Gamma with lower occurrence, are associated with increased transmissibility “compared to ancestral variants.”

“PAHO/WHO recommends that Member States continue their efforts to increase vaccination coverage for COVID-19 and improve adherence to public health measures for reducing SARS-CoV-2 virus transmission,” the update says. It also asks countries to continue to perform genomic sequencing of SARS-CoV-2 samples and to monitor changes in the incidence of COVID-19. Current PCR tests can detect Omicron and the other variants.

“Regarding the effectiveness of vaccines, PAHO/WHO highlights that current COVID-19 vaccines continue to be effective in preventing the development of severe illness and death. PAHO/WHO is working with technical partners to understand the potential impact of this variant on public health measures, including vaccines,” the PAHO Epidemiological Update notes.