The Department of Health has launched an investigation into a two-year-old boy's death from anthrax late last month.

The Tseung Kwan O toddler developed symptoms on May 27 and died three days later.

Consultant-in-charge of the department's Disease Prevention & Control Division Dr Tse Lai-yin said the boy had a sudden onset of fever and anorexia on May 27.

His condition deteriorated on May 30 with abdominal pain, vomiting and shortness of breath. He was taken to a private hospital but was certified dead shortly afterwards.

Dr Tse said the department is tracing the source of infection, adding that no other contacts have suffered from the illness.

She said the boy's family are asymptomatic and have been put under medical surveillance.

Anthrax is an acute infectious disease occurring mainly in livestock like cattle and sheep, but it can also infect humans.

Dr Tse said person-to-person transmission is very rare. She ruled out speculation from some reporters that it was a biological terrorist attack.

Anthrax infection is very rare in Hong Kong. There have been three other cases reported in the past 20 years.

Two of them in 1982 were occupationally acquired, and the remaining one in 1994 was a fatal sporadic case of intestinal anthrax involving a 13-year-old boy.

She stressed that there is effective antibiotic treatment for the disease. Early antibiotic treatment is essential because any delay can lessen the chances of survival.

Meanwhile, the Agriculture, Fisheries, & Conservation Department said its staff will pay special attention to any abnormal deaths of animals in their regular health checks at local farms.

No records of animals contracting anthrax have been reported in the last decade, it said.