Various studies have been carried out to determine the role of pigeons in the spread of avian influenza. These studies have determined that pigeons are resistant or minimally susceptible to infection with HPAIV or NPAIV and probably play a minimal epidemiological role in the spread of the viruses.

For further information see the following two articles:

Pathogenicity of a Hong Kong-origin H5N1 highly pathogenic avian influenza virus for emus, geese, ducks, and pigeons.
Perkins LE, Swayne DE

Pigeons were inoculated intranasally with A/chicken/Hong Kong/220/97 (H5N1) highly pathogenic avian influenza virus. They seemed resistant to infection not showing any clinical signs or gross and histologic lesions and the virus was not re-isolated.
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Susceptibility of pigeons to avian influenza.
Panigrahy B, Senne DA, Pedersen JC, Shafer AL, Pearson JE

Pigeons were inoculated with non-pathogenic avian influenza virus and highly pathogenic avian influenza virus. The pigeons remained clinically healthy and virus was not re-isolated.
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