When the Copa America basketball tournament got underway last month in the midst of a pandemic, the hosts in Cali, Colombia took no chances.
Players and staff from participating men's national teams from around Latin America lived in a local "bubble" without contact with outsiders; all were tested regularly for Covid-19.
Missing from the contest was Brazil. The country has been so ravaged by coronavirus, including a new and highly contagious home-grown variant known as P1, that Colombia would not permit the Brazilians to land on their soil.
A double header of soccer World Cup qualifiers was also called off this month after Colombia's health minister said he would not allow a charter flight of Brazilian footballers to land in Colombia for the game.
Sports are just the beginning. Brazil's neighbors and trading partners are taking steps to limit contact with South America's largest country - and contemplating more draconian ones. The fear is that the progress many nations in the region have made against Covid-19 could be reversed by new waves of infection from Brazil, whose out-of-control pandemic is incubating virulent new strains that are worrying medical experts worldwide.
"It is a very alarming situation and a regional threat," said Leda Guzzi, an infectious disease expert and member of the Argentina Society of Infectious Diseases.
Even crisis-torn Venezuela has plenty to say. On Sunday, Venezuelan President Nicolás Maduro called Brazil "the world's worst threat in terms of the coronavirus" and chastised its leader, Jair Bolsonaro, for his "irresponsible attitude."
Bolsonaro, who contracted Covid-19 last year and wears a mask only sporadically, has repeatedly downplayed the crisis, even as his country has tallied more than 12 million confirmed Covid-19 infections and nearly 300,000 fatalities, trailing only the United States. He has opposed lockdowns and touted unproven treatments such as the antimalarial drug hydroxychloroquine.
Bolsonaro's office did not respond to a request for comment. The president repeatedly has defended his government's handling of the pandemic.
In landlocked Paraguay, where Covid-19 cases are hitting record highs, the government on March 16 discouraged people from non-essential travel, citing Brazil's "high number of infections and record deaths from Covid-19."
Chile's government in early March ordered that all visitors from Brazil be taken to state-run quarantine hotels to do a Covid-19 PCR test, and be kept there if they tested positive. Those rules were toughened last week to impose a mandatory 72-hour stay in a transit hotel even with a negative test.
In Bolivia's department of Beni, a state-like area that shares a long land border with Brazil, Covid-19 cases are exploding in the cities of Riberalta and Guayaramerín, according to Ernesto Moisés, Beni's Secretary of Human Development.
Many Bolivians in this northern region live off trade and interaction with Brazil. Moisés is calling for border closures to help save lives.
"I think that now is a time for authorities to forget about politics and everything, we have to be tough because you can't do politics if everyone is dead," he said.
Fueling Brazil's deadly outbreak is a more contagious variant of the novel coronavirus, known as P1, which emerged in its northern Amazon region near the end of 2020 and now predominates in much of the country. Early studies suggest it can overcome some antibodies and increase a person's chances of reinfection.
The Pan American Health Organization (PAHO), the regional arm of the World Health Organization, said on Tuesday that the P1 variant had been detected in 15 countries in the Americas and was a major cause for concern.
In Argentina, which has been reluctant to close borders with Brazil, its top trading partner, calls for tougher rules are growing louder from scientists and regional leaders.
In a video meeting on Monday between the interior minister, health officials and regional governors, participants discussed potential measures including strengthening border security forces, with a focus on areas near Brazil, Paraguay and Bolivia, a government source familiar with the proceedings said.
Also under discussion is the possibility of speeding up vaccinations for border personnel, tightening rules for truckers carrying cargo across borders, and cracking down on travelers, including Argentines, coming from Brazil.
"Work is being done to strongly restrict entry from Brazil with drastic restrictions on the frequency of flights from the neighboring country," said a government source on Tuesday, who said restrictive measures would be defined in coming days.
Guzzi, the Argentine infectious disease expert, is among the health experts calling for border closures, restrictions on people coming from Brazil or mandatory confinement periods.
"What happens to Brazil has a very important impact on what happens in our national territory," she told Reuters. "If this (P1) variant takes hold in Argentina it can be very dangerous."
In Uruguay, a popular holiday spot for Brazilians, hospitals in towns and cities near the border with Brazil are reaching saturation level and running out of beds.
Once Latin America's best performer at containing the virus, Uruguay is now seeing cases soar. The country's average daily per capita rate of infection, at around 50 cases per 100,000, now exceeds that of Brazil, at 35 per 100,000, according to data on confirmed cases.
In Montevideo, health authorities last week launched a working group of specialists to analyze test samples to help track the entry of new variants, including P1. Uruguayan authorities confirmed they had detected the P1 and P2 Brazilian variants for the first time on Monday.
"The alarm bells are ringing", said Julio Pontet, president of the Uruguayan Society of Intensive Care Medicine. He said that the rise in Covid-19 cases in Uruguay's north-east region bordering Brazil were much worse than elsewhere.
Brazil, meanwhile, is on track for its worst month in the pandemic with already more than 40,000 deaths in what some local papers have branded "red March." Intensive care units in some cities are overwhelmed and have shortages of medicines.
Bolsonaro, who has declined the coronavirus vaccine, opposes business closures and social distancing measures. A number of state governors, who tightened restrictions last year, have done so again in recent weeks despite the president's protests. Brazilian businesses have also started to demand firmer action, with some like carmaker Volkswagen AG halting operations.
Many countries, however, remain reluctant to completely seal themselves off from Brazil, Latin America's top economy.
And PAHO, while concerned about Brazil's impact on the region, suggested full border closures were not the answer.
Jarbas Barbosa, PAHO Assistant Director, told Reuters that strong public health measures such as mask wearing, physical distancing, better surveillance and lockdowns when necessary remained the best hope for stopping the spread.
In Paraguay, though, local authorities say their country is at risk as long as neighboring Brazil remains a vector for coronavirus.
"We always say that when Brazil sneezes, Paraguay gets a cold," said Guillermo Sequera, director of health surveillance at the country's Health Ministry.