Final answer:
Young children are the demographic most at risk from respiratory syncytial virus (RSV). Infections in infants can be life-threatening.
Step-by-step explanation:
The demographic most at risk from respiratory syncytial virus (RSV) are young children. RSV infections are common in infants, and most people have been infected by the age of 2 years. Infections in infants can be life-threatening. RSV is highly contagious and can be spread through respiratory droplets from coughing and sneezing, making young children more susceptible to the virus.