China is the main importer of Brazilian chicken, with 562,000 tons in 2024, or more than 10 percent of the total, according to Brazil's ABPA meat association.

The EU, for its part, imported more than 231,000 tons of chicken last year, totaling 4.5 percent of Brazil's exports of the meat.

"To respect the agreements made with China and the European Union, exports are restricted" from Brazil as a whole -- in China's case for 60 days, Brazil's agriculture ministry said in a statement.

An outbreak of a new strain of "highly pathogenic avian influenza" (HPAI) has been confirmed on a farm in Montenegro in the southern state of Rio Grande do Sul, the ministry said.

While China and the EU suspended imports from Brazil as a whole, other countries may place restrictions on the affected region only.

The ministry said the virus could not be transmitted to humans "by the consumption of poultry meat or eggs."

Infections in humans can cause severe disease with a high mortality rate, according to the World Health Organization (WHO).

It says human cases detected so far are mostly linked to people who had close contact with infected birds and other animals, or contaminated environments.

The virus does not appear to move easily from person to person, according to the WHO.

Brazil says containment and eradication measures have been put in place.

The H5N1 bird flu was first detected in 1996 in China, but since 2020, the number of outbreaks among birds has surged, and an increasing number of mammal species has been affected.

In the United States this year, tens of millions of laying chickens have been culled, resulting in an egg shortage.

A three-year-old girl last month became Mexico's first human fatality from H5N1.