Gambian authorities have detected the highly pathogenic H5N1 avian influenza on a wild bird reserve, the ministry of agriculture said in a statement, less than one week after neighbouring Senegal reported an outbreak of the disease on a poultry farm, according to a report from Reuters.

Samples were collected from Gambia's Tanji Bird Reserve, around 20 kilometres from the capital Banjul, after several wild birds were reported dead.

The samples were sent to a laboratory in Dakar on April 1 and tested positive for High Pathogenicity Avian influenza (HPAI) type H5N1, said the statement, which was issued on Wednesday.

Authorities "are closely working together to help reduce the infection pressure at the wild bird level while working... to prevent the spill over to our poultry," it added.

Gambia is almost entirely surrounded by Senegal, which reported an outbreak of H5N1 bird flu on a poultry farm in the northwestern part of the country last Friday.

Senegalese authorities also detected the disease among wild birds last month.