Brazil is considering retaliation against trade partners that are refusing to import Brazilian beef suspected of carrying atypical mad cow disease.

Senior Brazilian officials say fears that Brazilian beef is unsafe for human consumption are unfounded and the international import restrictions are unjustified.

China and Japan are on a growing list of countries that have banned Brazilian beef imports. Chile became the first Latin American nation to halt imports from Brazil, despite Brazilian protestations the meat is safe to eat.

South Africa, Saudi Arabia and Jordan have announced bans and there are fears that other countries or regions may follow.

Livestock and agriculture analysts expected Brazil to announce new health measures to stamp out the problem. Instead, Brazilian officials went on record threatening retaliation against countries that stop importing the produce.

Outbreaks of bovine spongiform encephalopathy in the 1980s and 1990s caused hundreds of millions of dollars of damage to British and other economies, decimating livestock farms and related agriculture. In later years, scientists determined that, unlike typical BSE, livestock could often be affected by atypical BSE which wasn't a danger to public health.

Disagreements over effects of atypical BSE continue, however. A few atypical BSE outbreaks were recorded in the United States in 2012 with no known harmful effects on livestock industry there.

Livestock experts say BSE is diminishing worldwide and atypical cases are rare but the reaction of international importers of Brazilian beef indicates otherwise.

Chile this week joined five other countries that have banned imports of Brazilian beef, since a case of atypical mad cow disease was confirmed in December last year. Brazilian Foreign Trade Secretary Tatiana Prazeres said there were no reasonable grounds for the import bans.

She said Brazil is considering retaliation at the World Trade Organization if the countries don't lift the bans.

"There is no basis for these decisions on health parameters and the government is analyzing what measures will be taken," Prazeres said. "Taking action at the WTO is on our radar."

The ban by Chile is potentially hurtful for Brazilian trade because Chile is the largest importer of Brazilian beef.

Estimates of the impact on Brazilian beef trade remain unclear.

Prazeres estimated that 4.4 percent of the country's total beef exports were affected by the bans.

Despite those cutbacks by importers, however, Brazilian beef trade remains on the upswing.

Brazilian government officials have hinted international litigation at the WTO may be one of the options open to Brazil if the countries that have banned imports fail to review their decisions.

A diplomatic campaign is under way to point out that atypical BSE is extremely rare and only caused by random genetic mutation rather than contaminated animal feed.

The outbreaks of BSE in Britain and elsewhere in Europe from the 1980s onwards were traced to contaminated animal feed.

The disease affected more than 180,000 cattle in Britain and led to the slaughter of more than 4.4 million cattle during an eradication program.