All of the following diseases can be transmitted during the incubation period except

• Carrier: An infected person or animal that harbours a specific infectious agent ‘in the absence of discernible clinical disease’ and serves as a potential source of infection to others. • Incubatory carriers: Shed infectious agent during the incubation period of the disease (esp. during last few days of IP). For example: Measles, Mumps, Polio, Pertussis, Influenza, Diphtheria, Hepatitis B, HIV.