Can people receiving the nasal-spray flu vaccine made with the live weakened virus pass the virus to others?

In clinical studies, spreading vaccine viruses to close contacts occurred only rarely. The current estimated risk of getting infected with vaccine virus after close contact with a person vaccinated with the nasal-spray flu vaccine is low (0.6%-2.4%). Because the viruses are weakened, infection is unlikely to result in influenza illness symptoms since the vaccine viruses have not been shown change into typical or naturally occurring influenza viruses.

Last Reviewed: 10/18/2010

• Can the nasal-spray flu vaccine be given to patients when they are ill?
• Can a pregnant health care provider give the live nasal spray flu vaccine?
• Can family members of a pregnant woman receive the nasal spray vaccine?
• Should some people not get the live, attenuated nasal spray vaccine?
• What are the side effects of the seasonal live, attenuated nasal spray flu vaccine?

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