Brazilian health regulator Anvisa recommended on Friday that travel be restricted from some African countries due to the detection of a new COVID-19 variant, but President Jair Bolsonaro appeared to dismiss such measures.
Anvisa said its recommendation, which would need government approval to be implemented, was to immediately suspend flights from South Africa, Botswana, Lesotho, Eswatini, Namibia and Zimbabwe.
The EU and Britain are already tightening border controls as researchers look into whether the new mutation is vaccine-resistant.
Bolsonaro has been widely criticized by public health experts for his management of the pandemic, railing against lockdowns, often refusing to wear a mask in public and choosing not to get vaccinated. Brazil has the world's second-highest death toll from the virus, behind only the United States.
Before the Anvisa statement on Friday, Bolsonaro told supporters it made little sense to close borders.
"What madness is this?," Bolsonaro told supporters when asked if travel would be restricted. "The virus doesn't come in if you close the airport. It is already here."
The news of the variant hammered travel stocks in Brazil, with shares in airlines Gol and Azul plunging about 10%, while travel operator CVC posted an 8% fall and planemaker Embraer was down 7%.
In its technical note, Anvisa said that foreigners who have been to at least one of the six African countries cited in the prior 14 days should not be allowed to land in Brazil, while Brazilians arriving from those nations should be required to quarantine.
The health agency said "the new variant appears to have a higher transmissibility."