Which vaccine prevents a disease that can cause severe diarrhea in infants?

The Rotavirus vaccine is specifically designed to prevent rotavirus infections, which are a leading cause of severe diarrhea in infants and young children. Rotavirus is highly contagious and can lead to significant dehydration, frequent hospitalizations, and, in severe cases, can be life-threatening without treatment.

In contrast, the other vaccines listed protect against different infections that do not primarily cause diarrhea. The pneumococcal vaccine prevents diseases such as pneumonia and meningitis caused by the bacterium Streptococcus pneumoniae. The measles vaccine protects against measles, a viral infection characterized by fever, cough, and a distinctive rash, but does not typically cause severe diarrhea. The Hepatitis B vaccine provides immunity against hepatitis B virus, which primarily affects the liver and does not cause diarrhea as a primary symptom. Therefore, the choice of the Rotavirus vaccine is accurate because it specifically targets the cause of severe diarrhea in infants.