BCG vaccine linked to lower hospitalization rates for respiratory infections, sepsis
Researchers from Spain have learned that receiving the bacille Calmette-Guérin vaccine at birth may confer heterologous protection against hospitalization for respiratory infections and sepsis.
“Although we did not find a significant effect on child mortality, the study suggests that BCG vaccine may have significant beneficial effects on the health of pediatric patients from a developed country,” the researchers wrote in Clinical Infectious Diseases. “Additional research is needed to define the path toward obtaining unequivocal evidence on these issues that would support future robust, evidence-based adjustments in immunization policies.”
The researchers, from the translational pediatrics and infectious diseases section of Hospital Clínico Universitario de Santiago de Compostela in Spain, conducted a retrospective epidemiological and hospital-based surveillance study that covered 1997 to 2011. BCG was part of the immunization program in Spain until 1982 and administered to every newborn. Since then, however, only the Basque Country region continued to administer the vaccine. The researchers identified children aged younger than 15 years admitted for upper or lower respiratory infection, sepsis not related to tuberculosis and TB disease. They then evaluated the relationship between the hospitalization rates for the diseases and the geographic location the patient was born to control for influences other than BCG vaccination.
There were 464,611 hospitalizations during the time period. In Basque Country, the hospitalization rate related to respiratory infections not attributable to TB was lower compared with the rest of Spain, a total preventive fraction of 41.4%. The hospitalization rate was significantly decreased for all age groups in Basque Country. The hospital rates for sepsis not attributable to TB also were significantly lower in Basque Country, compared with the rest of Spain, a total preventive fraction of 35.7%. The hospitalization rates were only significantly decreased for children aged younger than 1 year.
The hospitalization rate for TB also was significantly decreased in Basque Country. The total preventive fraction was 74%, and the decreased hospitalization rate was significant for all children aged older than 1 year. There was no difference in child mortality rates between Basque Country and the rest of Spain.
“Epidemiological studies and randomized trials in Africa have shown that the BCG vaccine reduces child mortality, mainly by preventing neonatal sepsis and respiratory infections not attributable to TB,” the researchers wrote. “As mortality (both overall, and specifically attributable to sepsis and respiratory infection) is significantly lower in Spain (and developed countries in general) compared to Africa, there is no sufficient statistical power to detect variation in this setting.” – by Emily Shafer
Disclosure: The researchers report no relevant financial disclosures.