Pakistani authorities have intensified monitoring of over 800 poultry farms in the capital city following an outbreak of bird flu in five poultry farms there, an official said Saturday.

The deadly H5N1 bird flu virus was detected in three farms on May 22 and in two other farms on May 23 in Chak Shehzad, a suburb of Islamabad, state media reported, quoting Livestock Commissioner Dr. R.H Usmani.

Several thousand chickens were killed by the disease or culled later in these farms.

However, the official said that there had been no case of human infection by the virus.

The affected poultry have been kept in quarantine to stop further spread of virus, and livestock officials have started disinfection spray within area of three km where bird flu virus has been detected as precautionary measures, according to the report.

Besides, the poultry farm owners were also asked to adopt defensive measures to check the spread of bird flu, including using gloves and masks while working in the farms.

Source: Xinhua