ROME (AFP) - Bangladesh needs to step up its fight against bird flu, which is posing a "huge challenge" in the densely populated country, the Food and Agriculture Organisation (FAO) said Monday.

"The bird flu situation in Bangladesh remains serious and the country will have to engage in a long-term strategic campaign against highly pathogenic avian influenza in order to get the spreading H5N1 virus under control," the Rome-based UN agency said in a communique.

"Bangladesh has a real chance to get the virus under control, if it commits itself to a full-scale comprehensive national control campaign," said Joseph Domenech, the FAOs chief veterinary officer.

"FAO is ready to continue its assistance, and further international aid will be essential to support the country in this huge challenge," he added.

Since February, when a first outbreak of H5N1 was officially announced in the impoverished country, the virus has spread to nearly one-fifth of the country, FAO said, adding that Bangladesh is the second country in South Asia to be affected this year.

While Bangladesh is already implementing control and containment measures, "there is an urgent need for vigourously stepping up and extending current H5N1 control campaigns in order to prevent the virus becoming widely entrenched," FAO said.

The FAO recommended continued culling "at full scale in affected areas," strict controls of the movement of people, animals and goods and "basic biosecurity measures" such as disinfection and protective clothing.

"In addition to existing rehabilitation packages already offered to farmers, FAO suggested that Bangladesh develop a comprehensive scheme to encourage reporting, facilitate disease control and minimise impact of disease control on large and small poultry producers," the statement said.

"Public awareness campaigns are necessary to inform poultry producers and consumers about how to reduce virus spread and how to protect themselves," it added.

Bangladesh has about 220 million chickens and 37 million ducks in an industry that employs five million people directly, while millions of households rely on poultry production for income and food, FAO said.

The country is among the world´s most densely populated, with nearly 1,000 people per square kilometer (2,600 per square mile).

Experts fear the deadly H5N1 strain could mutate and develop the ability to pass from human to human.

So far there have been no reports of human infection in Bangladesh.

Wild migratory birds have been blamed for the global spread of the disease.