Brazil's Geography Provides Buffer Against U.S.-Style Bird Flu Epidemics

SAO PAULO - Brazil's unique geography, characterized by the Amazon rainforest to the north, mountain ranges along the Atlantic coast, and the Andes to the west, has played a critical role in shielding the country from a widespread bird flu epidemic similar to that experienced in the United States. Despite facing its first outbreak of highly pathogenic avian influenza in May 2025, Brazil has managed to maintain a considerable distance from the devastation seen in U.S. poultry farms.

The outbreak, which resulted in the culling of approximately 17,000 breeding chickens, has prompted significant precautionary measures across Brazil's poultry industry, which is responsible for 39% of global chicken exports. Since the initial case, meatpackers such as BRF and JBS have preemptively culled at least 141,000 healthy chickens, reflecting an aggressive strategy to mitigate the risk of further infections.

As of mid-June 2025, Brazil has not reported any new cases on commercial poultry farms for over a month, raising hopes among farmers that the situation is under control. This contrasts sharply with the U.S., where the avian flu has decimated millions of birds and resulted in prolonged trade bans. According to data from the U.S. Department of Agriculture, around 175 million birds have been culled in the U.S. since 2022 due to the virus.

Experts have pointed to Brazil's geographical features as a significant factor in its current success. "The Amazon basin acts as a natural filter, keeping migratory birds, which are key vectors for the virus, away from poultry farms in Brazil's interior," explained Guillermo Zavala, an avian health consultant with over three decades of experience in the poultry industry. This is in stark contrast to the United States, where migratory patterns of wild waterfowl have been identified as major conduits for avian influenza transmission.

Furthermore, Alex Jahn, a researcher at Oregon State University, highlighted that the Andes mountains may delay the entrance of new virulent strains of the virus into Brazil for several years. However, he cautioned that the risk remains as wild bird populations infected with the virus circulate more widely. "South American birds can migrate in various directions based on rainfall, unlike the north-south migration typical of the U.S., which complicates containment efforts," Jahn stated.

Despite these geographical advantages, the situation remains precarious. Recent evidence suggests that migratory birds have infected local Brazilian species, making bird flu endemic in the country. Masaio Ishizuka, a senior epidemiologist at Sao Paulo University, noted that while Brazil's poultry industry has been successful so far, the potential for future outbreaks persists, especially as the virus continues to spread globally, even reaching Antarctica for the first time in 2024.

In response to the first commercial outbreak, Brazil's chief veterinary officer, Marcelo Mota, announced new biosecurity measures aimed at zoos, parks, and conservation sites to enhance monitoring and prevention strategies. These measures include stricter controls at breeding facilities, which are supposed to have more rigorous biosecurity protocols compared to farms raising chickens for meat. According to Felipe Sousa, an assistant professor at Sao Paulo University, these measures include mandatory showers for workers and the use of clean uniforms, as well as physical barriers like fences to keep stray animals away from flocks.

Brazil's ability to contain the avian flu outbreak will be crucial not only for its domestic poultry industry but also for its international trade relationships. Following the initial outbreak, China imposed a trade ban on Brazilian poultry products, while other nations have implemented various restrictions. As the world's largest chicken exporter, Brazil must navigate these challenges carefully to maintain its position in the global market.

In conclusion, while Brazil’s geographical advantages have provided a temporary buffer against the spread of bird flu, experts caution that the threat is far from over. Continued vigilance and adherence to stringent biosecurity measures will be essential in safeguarding Brazil's poultry industry and ensuring the stability of its agricultural exports moving forward.