Kolkata, Aug 12 - The number of confirmed swine flu cases in West Bengal rose to 13 Wednesday, as a class eight student of a Kolkata school tested positive for the infection.

'Joseph Subhasish Mondal was brought to the Beliaghata Infectious Diseases Hospital Tuesday after displaying symptoms of the infection. His test results Wednesday were positive,' Tapas Sen, the state's nodal officer for swine flu, told IANS.

Mondal has been admitted to the hospital, where seven people - five confirmed and two suspects - are being treated for the virus infection.

Eight other confirmed cases have been discharged after treatment.