Health authorities of Brazil's southern state of Rio Grande do Sul on Monday confirmed the third death caused by A/H1N1 flu in the country, Xinhua reported.
The victim, a nine-year-old boy from the state's capital Porto Alegre, died on July 5, three days after being admitted to a hospital, news reports quoted the authorities as saying.
The boy suffered from chronic diseases, which collaborated to worsen his condition, officials said.
It was the second child to die from A/H1N1 in Brazil. Last Friday, the Health Ministry said an 11-year-old girl died from A/H1N1 on June 30 in Osasco, a city in the southeastern state of Sao Paulo.
In both cases, the diagnosis of A/H1N1 was made by postmortem examination.
The Porto Alegre case was also the second death by A/H1N1 flu in Rio Grande do Sul. Brazil's first victim of the disease, a 29-year-old truck driver from the small town of Erechim, died on June 28.
The health authorities said the Porto Alegre boy caught the flu from his teenage brother, who had contacted a teacher who was infected during a trip to Argentina.
The truck driver caught the disease during a trip to Argentina , but it is not known yet how the girl from Osasco was infected. Several of her relatives were also diagnosed with A/H1N1 flu.
The ministry considered the cases of the girl and her family as exceptions, saying all other domestic transmission cases could be linked to a patient who was infected abroad.
There are 1,027 confirmed cases of A/H1N1 flu in Brazil, according to the latest figures released by the Brazilian Health Ministry.