What is a classic manifestation of pertussis?

A classic manifestation of pertussis, commonly known as whooping cough, is a dry, hacking cough that often worsens at night. This cough is characterized by a series of rapid coughs followed by a high-pitched "whoop" sound when the person inhales, which can be particularly distressing and is a hallmark feature of the infection.

In the early stages of pertussis, the cough may be mild and resemble that of a common cold, but as the infection progresses, the cough becomes more severe and paroxysmal. This can lead to significant difficulty in breathing and may result in vomiting or exhaustion after coughing fits.

The other choices involve symptoms that are not typically characteristic of pertussis. Severe chest pain is not commonly associated with this condition, while high fever and lethargy may indicate other infections but are not specific to pertussis. Additionally, a runny nose and sneezing are more indicative of upper respiratory infections rather than the distinctive cough associated with whooping cough. This understanding of the symptomatology of pertussis is critical for accurate diagnosis and treatment.