Pneumococcal conjugate vaccines (PCVs) have been demonstrated to be beneficial in the prevention of pneumonia and invasive pneumococcal infections since the early 2000s. The Galician area was the first in Spain to use PCV in regular newborn vaccination in 2011. Using an ecological research design, researchers wanted to examine the direct and indirect impacts of PCV immunisation on all-cause pneumonia in the region across different age groups. They used a hospital-based illness registry to compute the yearly hospitalisation rates. Within the registry, they discovered all-cause pneumonia, pneumococcal pneumonia, and pneumococcal invasive infections. The rates of hospitalisation were calculated and compared across three research periods: pre-vaccination, early-vaccination, and routine-vaccination. They found 114,873 all-cause pneumonia hospitalizations in Northern Spain, with 24,808 being diagnosed with pneumococcal pneumonia. The bulk of the people were above the age of 64. Hospitalizations for all-cause pneumonia increased from 20.6 and 21.4/10,000 to 28.4/10,000, owing to a large number of cases among the elderly. In contrast, there was a net decrease in the incidence of hospitalised pneumococcal pneumonia from 6.3/10,000 to 2.4/10,000 instances.

Thus, regular newborn immunisation may have resulted in a reduction in pneumococcal pneumonia in both babies and the elderly. However, a surprising rise in all-cause pneumonia was reported in Galicia, which was mostly ascribed to an increase in the senior population.