Effect of 7 and 13-Valent Pneumococcal Conjugate Vaccines Different Number of Doses for Pneumonia Control in 2008 and 2010 Birth Cohort Children

María Hortal^1*, Miguel Meny², Miguel Estevan³, Fernando Arrieta⁴, Hilda Laurani⁵

¹Basic Sciences Program, Montevideo, Uruguay.
²Statistics Department, Montevideo City Council, Montevideo, Uruguay.
³Radiology Unit, Children’s Hospital, Montevideo, Uruguay.
⁴Vaccination Department, Honorary Committee against Tuberculosis (CHLA), Montevideo, Uruguay.
⁵Honorary Committee against Tuberculosis (CHLA), Montevideo, Uruguay.

DOI: 10.4236/wjv.2015.51005                

Abstract

The 7-valent pneumococcal conjugate vaccine (PCV) was introduced in Uruguay in March 2008. In April 2010, it was replaced by PCV13. Surveillance of both vaccines was performed on hospitalized children with consolidated pneumonia. The effect of different number of vaccine doses was evaluated in 2008 and 2010 birth cohorts vaccinated with PCV7 and PCV13 respectively. The study aims to estimate the effects of PCV7 and PCV13 different number of doses on consolidated pneumonia, through the study of hospitalized children from 2008 and 2010 birth cohorts. Vaccination records of every child were available providing precise vaccination data; therefore a new approach was used to estimate PCVs effect. Incidence rate was calculated for each year of the study and for the different number of vaccine doses used each year. Exposure was calculated as person per year and rate ratio values determined the decrease of consolidated pneumonias. This decrease in percentage was estimated as the difference between the incidence with no vaccine and the incidence of every one of the doses. Incidence rate ratio revealed significant values for the three vaccine doses of PCVs for both cohorts. Upon comparing incidences, significant reduction percentages of consolidated pneumonia admissions were found. The reduction percentage of consolidated pneumonia for fully vaccinated (3 doses) patients was 69.3% and 84.6 % for PCV7 and PCV13, respectively. These results confirm that PCV7 and PCV13 are highly effective for reducing pediatric hospitalizations due to consolidated pneumonia, as reported by other national publications and demonstrated by international researchers.

Keywords

Pneumococcal Conjugate Vaccine, Pneumonia, Birth Cohort, Incidence Rate, Dose Schedule

Conflicts of Interest

The authors declare no conflicts of interest.

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