Vietnam’s health ministry on Tuesday confirmed four more cases of influenza A (H1N1) to raise the country’s total to 56 cases, and a senior epidemiologist warned about the possibility of more dangerous strains emerging.

The Health Ministry said the man’s wifes who shared the same flight, had earlier tested positive for the virus.

Two other cases confirmed Tuesday were a 15-year-old girl and her brother who is a year younger. Both are US citizens and arrived at Tan Son Nhat Airport in Ho Chi Minh City last Thursday.

The fourth case was a 17-year-old girl, but no more details were made available about her at this point.

Doctors from the Tien Giang General Hospital in the eponymous province said they discharged Tuesday three H1N1 flu patients who had recovered. These included an 18-year-old overseas Vietnamese youth, Truong Minh Tri, who tested positive on June 12.

The Health Ministry confirmed there has been no fatal case of influenza A (H1N1) in Vietnam so far and the condition of all patients under quarantine has improved.

Bird flu recurs

Hoang Van Nam, deputy head of the Animal Health Bureau under the Ministry of Agriculture and Rural Development, said bird flu has recurred among fowl in Quang Ninh Province.

As of Monday, the H5N1 virus has been detected in ducks and chickens raised by four families in Lien Hoa Commune in the province’s Yen Hung District, killing 504 of a total of 1,830 birds.

Diep Kinh Tan, deputy minister of Agriculture and Rural Development, blamed several localities for being indifferent in fighting the flu, noting that these provinces had asked for few vaccines.

He instructed authorities in Quang Ninh Province to quarantine the birds if they show symptoms of bird flu and to construct facilities for the purpose.

Central animal health authorities have reported more than 154 million birds nationwide have been vaccinated this year, including 80 million ducks and 83.5 million chickens.

Dangerous combination

Nguyen Tran Hien, director of a National Institute of Hygiene and Epidemiology, on Tuesday warned the influenza A (H1N1) epidemic could become worse in the winter months.

He said a possible new strain of the virus that is a combination of the H1N1 and H5N1 viruses could prove more dangerous, capable of inflicting fatality rates of more than 50 percent, he said.

He also said the current strain of influenza A (H1N1) had already become more dangerous with the World Health Organization (WHO) warning the fatality rate could rise as it spreads in developing countries where healthcare facilities are limited.

The WHO, which has already declared the virus a global pandemic, advised governments to prepare for a long-term battle against it, Reuters reported Tuesday.

It cited latest WHO statistics as saying the H1N1 virus has infected over 52,700 people worldwide, killing at least 237.

Source: TN, VNA