Changes in childhood pneumonia and infant mortality rates following introduction of the 13-valent pneumococcal conjugate vaccine in Nicaragua.
BACKGROUND
In 2010, Nicaragua became the first developing nation to add 13-valent pneumococcal conjugate vaccine (PCV-13) to its national immunization schedule, using a "3+0" dosing schedule. We assessed changes in incidence rates of health facility visits for childhood pneumonia and infant mortality after PCV-13 introduction in the Department of León, Nicaragua.


METHODS
We collected visit diagnoses from all 107 public health facilities in León between 2008 and 2012. We compared rates of pneumonia hospitalizations, ambulatory visits for pneumonia and infant mortality during the prevaccine (2008-2010) and vaccine (2011-2012) periods among different age groups of children using generalized estimating equations, accounting for clustering by municipality. Exposure time was estimated by official municipality population estimates.


RESULTS
The adjusted incidence rate ratio for pneumonia hospitalization in the vaccine versus prevaccine period was 0.67 (0.59-0.75) among infants and 0.74 (0.67-0.81) among 1-year olds. The adjusted incidence rate ratio for ambulatory visits for pneumonia was 0.87 (0.75-1.01) among infants, and 0.84 (0.74, 0.95) among 1-year olds. The adjusted incidence rate ratio for infant mortality was 0.67 (0.57-0.80). We also observed lower rates of health facility visits for pneumonia among age groups (2- to 4-year old and 5- to 14-year old) not eligible to receive PCV-13.


CONCLUSIONS
Within the first 2 years of a PCV-13 immunization program in Nicaragua, we observed lower rates of hospitalizations and ambulatory visits for pneumonia among children of all ages and a lower infant mortality rate. Lower rates of pneumonia among age groups not eligible to receive PCV-13 suggest an indirect effect of the vaccine.
From the *Department of Family Medicine, University of North Carolina School of Medicine, Chapel Hill, NC; †Department of Microbiology, National Autonomous University of Nicaragua, León, Nicaragua; ‡Department of Biostatistics, UNC Gillings School of Global Public Health, Chapel Hill, NC; §Sistemas Locales de Atención Integral a la Salud, León (SILAIS-León); ¶Hospital Epidemiology, ||Department of Pediatrics, Hospital Escuela Oscar Danilo Rosales Argüello (HEODRA), León, Nicaragua; **Division of Infectious Diseases, Duke University School of Medicine, Durham, NC; and ††Division of Infectious Diseases, University of North Carolina School of Medicine, Chapel Hill, NC.
Sylvia
S
Becker-Dreps
Erick
E
Amaya
Lan
L
Liu
Gilberto
G
Moreno
Julio
J
Rocha
Rafaela
R
Briceño
Jorge
J
Alemán
Michael G
MG
Hudgens
Christopher W
CW
Woods
David J
DJ
Weber
D000293:Adolescent; D000553:Ambulatory Care / Q000706:statistics & numerical data; D002648:Child; D046688:Child Mortality; D002675:Child, Preschool; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D007223:Infant; D007226:Infant Mortality; D009527:Nicaragua / Q000453:epidemiology; D022242:Pneumococcal Vaccines / Q000008:administration & dosage*; D011018:Pneumonia, Pneumococcal / Q000453:epidemiology / Q000401:mortality* / Q000517:prevention & control; D018074:Vaccines, Conjugate / Q000008:administration & dosage
C538862:13-valent pneumococcal vaccine; D022242:Pneumococcal Vaccines; D018074:Vaccines, Conjugate