A groundbreaking conservation effort to bring the stunning Spix’s macaw back from extinction has hit a devastating snag. Seven of these brilliant blue birds—including one precious chick born in the wild—have tested positive for a lethal virus that could derail the entire reintroduction program.

The Spix’s macaw was declared extinct in the wild in 2000, making this Brazilian conservation project a last-chance lifeline for the species. Under the blazing sun of Brazil’s Caatinga shrubland, these unmistakable turquoise birds had finally begun soaring through their native skies again. But white patches now mar some of their brilliant blue feathers—a telltale sign of circovirus infection.

Circovirus causes beak and feather disease, a highly contagious condition with no known cure. The disease can cause feather deformities, beak malformation, and dangerous immune system suppression in parrots, macaws, and related birds. What makes this outbreak particularly alarming is that circovirus has never before been detected in wild birds anywhere in Brazil or South America—the virus is native to Australia.

The timing couldn’t be worse. Six of the infected birds were being prepared for release later this year as part of the carefully orchestrated reintroduction program. Now, BlueSky, the Brazilian organization managing the breeding center in Curaçá, Bahia, faces the heartbreaking challenge of containing the outbreak while preserving hope for one of the world’s rarest birds. The discovery has created a serious rift among conservationists about how—or whether—to proceed with releasing more birds into the wild.