Antoinette Joy had hired an air ambulance from Mayurpur Airport in Sonbhadra district to airlift his ailing wife Malcolm Single, who showed symptoms of H1NI influenza, to Delhi on Tuesday night.
The plane had to make an emergency landing after the condition of the patient worsened, an airport official said.
She is undergoing treatment at a private hospital in the city. The doctors have sent the patient's blood sample to Lucknow for tests, an official from the hospital said.