The highly-mutated Omicron variant of SARS-CoV-2 virus has been reported from 57 countries and across all regions of the World Health Organization and most of these cases are travel related, said the WHO in its weekly epidemiological report.
This comes even as early reports from Australia suggest a hard-to-detect “Omicron-like” variant.
Variant of concern
Omicron is the fifth SARS-CoV-2 variant to be designated a variant of concern (VOC) by the WHO after Alpha, Beta, Gamma and Delta variants. The first known laboratory-confirmed case of Omicron was identified from a specimen collected on November 9 in South Africa and reported to WHO on November 24.
The report said that limited data made it challenging to assess changes in disease severity due to Omicron.
As of December 6, it added, “all of the 212 confirmed cases identified in 18 European Union countries for which there was information available on severity were asymptomatic or mild. While South Africa saw an 82 percent increase in hospital admissions due to Covid-19 (502 to 912) during the week of November 28 – December 4, the proportion of these with the Omicron variant is not yet known.”
Further, it said, even if the clinical severity was equal or lower than the Delta variant, “it is expected that hospitalisations will increase if more people become infected and that there will be a time lag between an increase in the incidence of cases and an increase in the incidence of deaths.”
In South Africa, where Omicron was first reported, the case incidence of Covid-19 has been on the rise. The week ended December 5 saw a 111 per cent increase in new cases compared to the previous week.
Cause of rise unknown
“While drivers of these increases remain unknown, it is plausible that spread of Omicron in combination with enhanced testing following the declaration of a VOC play a role, together with the relaxation of public health and social measures (PHSMs) and sub-optimal immunisation coverage,” the report said.
In South Africa 25.2 per cent of the total population is fully vaccinated.
Also see: Nearly all cases of Omicron Covid variant in Delhi and Rajasthan are asymptomatic
Recently, the European Centre for Disease Prevention and Control forecast that if 1 per cent of SARS-CoV-2 infections are due to the Omicron variant, it will become dominant in Europe, comprising over 50 percent of the new infections by January 1, 2022.
“Ongoing and planned epidemiological studies, including detailed cluster investigations, contact-tracing and household transmission studies, coupled with neutralisation studies from people previously vaccinated or infected and studies of vaccine effectiveness will help improve our understanding of the interplay between increased transmissibility and immune escape as drivers of increased transmission,” the report said.
Weekly deaths increase
Globally, the weekly Covid case incidence plateaued in the week (November 29 — December 5), with over 4 million confirmed new cases reported, similar to the number reported in the previous week, the report said.
However, new weekly deaths increased by 10 percent as compared to the previous week, with over 52,500 new deaths reported. As of December 5, nearly 265 million confirmed cases and over 5.2 million deaths have been reported globally, the WHO said.