Brazilian health authorities authorized Covid-19 vaccines for children age five to 11 on Wednesday, as South America's most populous country faces a rapid increase in cases due to holiday gatherings and the arrival of the Omicron variant.

The final green light by Brazil's Ministry of Health comes three weeks after the nation's independent medicines regulator, Anvisa, declared Pfizer-BioNTech's child-size dose to be safe and effective.

"To all those parents who want to vaccinate their children, the Ministry of Health will guarantee doses of the (Covid) vaccine," said Health Minister Marcelo Queiroga in Brasilia.

Controversy abounded in Brazil until Wednesday's announcement, with many alleging an improper delay by the government.

President Jair Bolsonaro, who did not get vaccinated and said he will not immunize his 11-year-old daughter Laura, asked weeks ago to publish the names of those responsible for Anvisa's decision, unleashing a wave of threats.

The final authorization comes amid a rising rate of infections in the country and a struggle to repair the health ministry's hacked Covid website.

Brazil's Health Ministry recorded 18,759 new cases in 24 hours in its latest data released Tuesday, the highest level since October 5.

Brazil Covid vaccination
The number of Covid cases has started to rapidly increase in Brazil, due to the arrival of the Omicron variant, holiday gatherings, and a backlog of data Photo: AFP / MAURO PIMENTEL

The seven-day average also rose to 9,876 new cases, up from 5,033 the previous Tuesday, and 3,386 the week before that.

The rapidly increasing rate of new infections follows a trend seen in other nations where Omicron has taken hold.

"We will have growth of the Omicron variant here as in all the other countries," said Ethel Maciel, an epidemiologist with the Federal University of Espirito Santo.

"The Christmas and New Year holidays, and the Omicron variant contributed a lot," she explained.

But she also noted that Brazil "has a backlog of data due to a problem with the tracking system," meaning the site is currently being updated which inflates the number of cases.

The issue stems from a cyberattack last month that disabled the government's website for tracking infections and deaths, while allowing hackers to steal personal data and delete citizens' health passes.

Authorities in Rio de Janeiro, wary of Omicron's increasing impact, on Tuesday announced the cancelation of next month's carnival street celebrations.

After the United States, Brazil has the second highest number of deaths due to Covid with around 620,000 since the global pandemic began.

Copyright AFP. All rights reserved.