Which of the following conditions requires droplet precautions?

The condition that requires droplet precautions is pertussis. Droplet precautions are necessary for infections that are transmitted through respiratory droplets generated by coughing, sneezing, or talking. Pertussis, also known as whooping cough, is highly contagious and is spread through respiratory droplets when an infected person coughs or sneezes.

In a healthcare setting, implementing droplet precautions involves wearing a mask, ensuring the patient is in a private room, and taking extra care with hand hygiene. This is particularly important to prevent the spread of pertussis to susceptible individuals, such as infants and those who are unimmunized.

Other conditions such as measles, while highly contagious, primarily require airborne precautions due to their transmission via smaller airborne particles that can remain suspended in the air. Severe Acute Respiratory Syndrome (SARS) is also primarily aerosolized and requires airborne precautions. Chickenpox, like measles, is transmitted airborne and requires airborne precautions due to the virus being capable of remaining suspended in the air and causing infection. Thus, among the options provided, pertussis specifically necessitates droplet precautions, distinguishing it from the other listed conditions.