Russian flu may refer to:

• Influenza A virus subtype H2N2#Russian flu, the conjectured cause of the 1889–1890 flu pandemic
• Influenza A virus subtype H1N1#Russian flu, the 1977-1978 flu epidemic
• "Russian Flu", the 5th episode of the 1st season of the television series Northern Exposure
• Russian Flu, a 1937 Swedish comedy film

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