Effect of community-wide conjugated pneumoccal vaccine administration on the disease burden of a tertiary children's hospital

Pneumococcus is the reason of 11% of childhood mortality worldwide. It is the most common agent responsible for several bacterial invasive diseases, namely bacteremia, bacteremic pneumonia and meningitis. Pneumococcus is also the leading cause of community acquired pneumonia, otitis and sinusitis, three of most frequently encountered problems at admission to hospitals. Preventing diseases due to this particularly important pathogen is definitely among primary health care concerns with high priority. Vaccines against pneumococcus with high efficacy can possess major role in reaching such an aim. Conjugated pneumococcal vaccine has been administered in Turkey since 2008. In this study, it is evaluated whether the conjugated pneumococcal vaccine generated a positive effect in our hospital on disease burdens of pneumonia, otitis, sinusitis, sepsis and bacteremia after introduction into routine national immunization program. In this study, no decrease is observed in numbers of pneumonia, otitis or sinusitis after introduction of pneumococcal vaccine. There are many reports telling no decreament in disease burdens of non-invasive pneumococcal diseases. There are many centers considering those data consistent with the fact as production of antibodies against pneumococcus, which is stimulated after vaccine administration, is not the most crucial step in preventing non-invasive diseases. However, data from our study cannot be interpreted as a supportive feature for this argument when massive increase in total admission numbers to our hospital taken into account. Despite the increase of total admission numbers to our hospital, we demonstrated a statistically significant decrease in numbers of pneumococcal sepsis and meningitis of all causes in our hospital. Pneumococcal menengitis are recorded in low numbers throughout all periods within study, possibly due to low obtainment rates from clinical specimens as we evaluated many children after referral to our tertiary hospital, most of whom were probably given some doses of antibiotics with a suspicion of meningitis before arrival to our center. It is noteworthy that a dramatic increase in sepsis and menengitis due to serotypes not included in conjugated pneumococcal vaccine is present after introduction of routine administration of conjugated vaccine.