Does pneumococcal vaccine reduce influenza morbidity in humans?

A retrospective study was conducted to verify the possibility that people immunized with pneumococcal vaccine (PV) show lower morbidity not only for pneumonia but also for influenza. A total of 450 individuals were enrolled between 1999 and 2003 and allocated to one of the following groups: (A) not vaccinated; (B) immunized with PV during 1999; (C) immunized with anti-influenza vaccine (Flu-V) each year; and (D) immunized with PV once in 1999 and Flu-V every consecutive year. People from group B showed significantly lower percentage of influenza-related diseases during the year 2000 in comparison with those from group A (p < 0.01), whereas in the course of 2001 the morbidity of patients from group B was lower compared with the other groups (p < 0.01). The results point to a way to decrease the morbidity of influenza-related diseases by immunization with PV only, at least for 2–3 years, avoiding Flu-V administration and permitting considerable saving for health care providers. Therefore, it is concluded that PV can reduce the morbidity of influenza at a greater rate than the Flu-V.