'We are killing ourselves' Vast fires rage across South America

'Blue, our sky is for ever blue!" effuses the official anthem of Rondônia, a UK-sized chunk of the Amazon in the western reaches of Brazil. But the "pure crystalline" heavens celebrated by those lyrics have vanished in recent months.

- Tom Phillips

Huge tracts of South America have been blanketed in smoke from largely man-made wildfires that are raging from Ecuador's droughtstricken capital to Paraguay's Chaco forest to the backlands of the greatest tropical jungle on Earth.

The smoke has been so dramatic that passenger planes have been unable to land in Rondônia's riverside capital, Porto Velho, and schools have been forced to close.

The government polyclinic run by Dr Lilian Samara de Melo Lima has seen a surge in patients suffering respiratory complaints, migraines and eye inflammation.

"These days we can't even see the other bank of the river," said the GP as she sheltered inside her clinic from the smog.

Lima, 45, was born and raised in Rondônia and has witnessed the toxic impact of wildfires before, as cattle ranchers and soy farmers use the Amazon's annual "burning season" to clear land and carve new properties out of the region's fastshrinking rainforests.

"But this year has been truly atypical," she added, blaming man's "devastating, predatory, reckless" march into areas that a few decades ago were largely unexplored.

For Porto Velho's 500,000 residents, the blazes have been suffocating. "We're breathing in so much detritus," said its health secretary, Marilene Penati, a paediatrician.