If a five-year-old child is exposed to pertussis after the mother declined boosters, what will occur?

• A. The child will have an immune response to the infection.
• B. The child will show no symptoms.
• C. The child will be immune due to maternal immunity.
• D. The child will need immediate medical intervention.

Answer: (A)

The correct answer is that the child will have an immune response to the infection. When exposed to pertussis (whooping cough), the child's immune system will recognize the Bordetella pertussis bacteria as a foreign invader. This recognition triggers an immune response, which includes the activation of immune cells and the production of antibodies specific to the pathogen.

Although the child may not have had a recent booster vaccine, their immune system is capable of responding to infections through innate and adaptive immunity. The initial exposure to the bacteria may lead to symptoms of whooping cough, such as severe coughing fits, but the body's response helps to clear the infection over time. This natural immune response is crucial for the development of immunity against pertussis.

In terms of maternal immunity, it is essential to highlight that any immunity passed from the mother during pregnancy wanes over time, particularly for a disease like pertussis, which is not typically passed through breast milk. Therefore, while maternal antibodies may provide some level of protection shortly after birth, they are unlikely to be sufficient if the child has not received the necessary vaccinations. Immediate medical intervention might be necessary depending on the severity of the infection, but simply being exposed does not guarantee that medical intervention is required.