PORTO VELHO (Brazil) • Lingering smoke in the Amazon has caused concern among Brazilians who say that respiratory problems - particularly among children and the elderly - have increased as fires in the region rage.

"The kids are affected the most. They're coughing a lot," said Ms Elane Diaz, a nurse in the Rondonia state capital of Porto Velho, as she waited for a doctor's appointment at a city hospital with her five-year-old-son Eduardo on Tuesday.

"They have problems breathing. I'm concerned because it affects their health."

The number of people treated for respiratory issues increased sharply in recent days at the local Cosme e Damia Children's hospital.

"This period has been very tough. The dry weather and the smoke cause many problems for children, such as pneumonia, coughing and secretion," Dr Daniel Pires, a paediatrician and the hospital's adjunct-director told the Folha de S. Paulo newspaper.

"From Aug 1 to Aug 10, the median (number) of cases was about 120 to 130 children with respiratory problems. From Aug 11 to (Aug 20), it went up to 280 cases," he said.

Growing fears over the health consequences are emerging as the number of fires in Brazil surges, with more than 77,000 documented by the country's National Space Research Institute in the last year. About half of the fires occurred in the Amazon region, with most in the past month.

Attention to the issue has largely been overshadowed by growing acrimony between Brazil and European countries seeking to help fight Amazon fires.

At a summit in France this week, Group of Seven nations pledged to help fight the flames and protect the rainforest by offering US$20 million (S$28 million), in addition to a separate US$12 million from Britain and US$11 million from Canada.

But Brazilian President Jair Bolsonaro, a far-right climate sceptic who took office this year with a promise to boost development in Latin America's biggest economy, questioned whether offers of international aid mask a plot to exploit the Amazon's resources and weaken Brazilian growth.

While many of the recorded fires this year were set in already deforested areas by people clearing land for cultivation or pasture, the Brazil government's figures show that they are much more widespread this year.

Medical experts in the area said that when exposed to smoke, residents can suffer from rhinitis, sinus and respiratory problems such as asthma and bronchitis, while chronic exposure can also lead to pulmonary illnesses, including emphysema.

ASSOCIATED PRESS