Correct option is B
Correct Answer (b):
The short incubation period of the influenza virus means that infected individuals can transmit the virus before their immune system has fully responded. This increases the risk of spreading the virus to others, particularly vulnerable populations such as the elderly, young children, and those with compromised immune systems. The rapid spread of influenza and the ability of the virus to infect individuals quickly emphasize the need for annual immunization to provide immunity before the flu season starts.
Additional Information:
Option (a): While antigenic variation is important and is a reason for updating the vaccine annually, the short incubation period of influenza has a more immediate impact on why the virus spreads so rapidly. Immunization helps mitigate the spread before individuals develop symptoms.
Option (c): Influenza does not have a longer incubation period. The virus typically has a short incubation period, which makes the prompt response of vaccination critical. The virus does not wait for immune cells to fully react before it starts infecting others.
Option (d): Repeated immunization is actually beneficial, as it boosts the immune system's ability to respond effectively to future infections. It helps create a stronger immune memory, especially in high-risk groups, rather than diminishing the immune response.
