Characterization of Adverse Events Following Childhood Immunizations in Pinar del Río, Cuba

Area of Science:

• Pediatrics
• Immunology
• Public Health

Background:

• Cuba's national childhood immunization program, established in 1962, includes adverse event surveillance since 1999.
• The expected rate of adverse events is 50 per 100,000 vaccine doses.
• Pinar del Río Province reported higher-than-expected adverse event rates in 2017, prompting this investigation.

Purpose of the Study:

• To characterize the frequency and types of adverse events following immunization in children in Pinar del Río Province during 2017.

Main Methods:

• Analysis of 487 adverse event reports in children aged 2 months to 14 years from January 1 to December 31, 2017.
• Data collected via epidemiological surveys, including demographics, vaccine details, and clinical manifestations.
• Calculation of adverse event rates per 100,000 vaccine doses administered and comparison with expected rates.

Main Results:

• The overall adverse event rate was 305.6 per 100,000 doses.
• Highest rates observed in infants under 1 year, Guane Municipality, with the pentavalent vaccine (DTwP-HB-Hib), and administration into the anterolateral thigh.
• Fever was the most common symptom; severe induration, hypotonic-hyporesponsive episodes, persistent crying, and rashes occurred more frequently than anticipated.

Conclusions:

• Adverse event rates in Pinar del Río are comparable to national and global figures.
• The pentavalent vaccine (DTwP-HB-Hib) was identified as the most reactogenic among childhood vaccines.
• The absence of severe adverse events underscores the overall safety of childhood immunization in Cuba.