Bird flu has resurfaced in parts of Asia, with human deaths reported in Indonesia and China and fresh outbreaks plaguing other countries during the winter months when the virus typically flares.

Indonesia, the nation hardest hit by the H5N1 virus, announced its 93rd death on Friday. A 47-year-old man died a day earlier in a Jakarta hospital, said Health Ministry spokesman Joko Suyono. The man fell ill on Dec. 2 and was admitted with flu-like symptoms, becoming Indonesia's 115th person infected with the disease.

In China, the military in eastern Nanjing banned the sale of poultry this week after a father and son came down with the disease earlier this month. Health officials confirmed the 24-year-old man died from the virus a day before his father, 52, became sick. It was the country's 17th bird flu death.

The two were believed to have eaten a traditional dish known as "beggar's chicken," in which the bird is wrapped in lotus leaves and baked. However, the cause of infection remained unclear.

Most human cases have been linked to contact with sick birds, and experts say that no human bird flu cases have ever been traced to eating properly cooked poultry or eggs.

The father is recovering after taking the antiviral Tamiflu, said Hans Troedsson, World Health Organization representative in China. More than 80 people who had contact with the family were being monitored for symptoms.

Local animal health officials said last week no H5N1 outbreaks had been detected among the province's poultry, but Troedsson said sick birds typically are not reported prior to human deaths in China — a sign the country's surveillance systems need to be improved.

The virus has killed 208 people worldwide since it began ravaging Asian poultry stocks in late 2003, according to the WHO.

Scientists say it is impossible to predict what the H5N1 virus will do, but more bird flu outbreaks often occur when temperatures drop as winter sets in.

Officials in Pakistan were investigating the country's first suspected bird flu cases Friday after two poultry farm workers died this week after being hospitalized with flu-like symptoms in Peshawar, said Khushdil Khan, medical superintendent of the Khyber Teaching Hospital.

Blood samples were sent to the Health Ministry in Islamabad for testing, but the results have not been confirmed, Khan said. Pakistan has grappled with bird flu outbreaks among poultry for the past two years, but no human cases have been reported.

Meanwhile, the disease has resurfaced in several provinces across Vietnam in recent months, killing or forcing the slaughter of thousands of birds. So far, 46 people have died from the virus nationwide.

Hong Kong closed its famed Mai Po bird sanctuary to the public for three weeks starting Friday after a wild gray heron discovered nearby tested positive for the virus. Russia and Poland also have experienced recent outbreaks among poultry, but neither have detected human cases.