In January 2012, PCV13 was introduced into immunization program in Argentina, 2+1 schedule for <2 years. The aims of this study were to evaluate the impact of PCV13 on Pneumococcal Pneumonia (PP) burden, and to describe epidemiological-clinical pattern of PP during the post-vaccination period.
PP discharge rates per 10,000 hospital discharges were compared between the pre-vaccination period 2007-2011 (preVp), the year of intervention (2012) and the post-vaccination period 2013-2019 (postVp).
Reduction in PP discharge rates was observed in patients <5 years (34.7%) in 2012 and 15.3% in postVp; these changes were not significant. Of 78 PP cases, 53.8% were male; 21.8% <2 years; 29.5% (23/78) had a complete PCV13 schedule (1 immunosuppressed case); 34.6% (27/78) had underlying diseases; 69.2% had complications (pleural effusion 69.2%, necrotizing pneumonia 10.3%, pneumothorax 9.0%, lung abscess 5.1%). Other clinical manifestations combined with PP were: sepsis 12.8%, meningitis 1.3% and peritonitis 1.3%. No case died. PP was more associated with age ≥84 months between 2012-2015 vs 2016-2019 [OR 4.68(1.09-23.10)].
After PCV13 introduction a reduction in PP discharge rates was observed in hospitalized children <5 years. PP cases affected older children
in the first years posV.