Purpose: Prevention of pneumonia in the elderly is an important health issue, and pneumococcal vaccination is thought to be effective in preventing pneumonia. We investigated the effects of pneumococcal vaccination among the elderly living on two islands.
Methods: We conducted a comparison study before and after vaccination. The study subjects (123 men and 229 women) were elderly (age ≥ 70 years), and were living on two islands of Hagi City, Yamaguchi Prefecture. They were vaccinated between December 2008 and February 2009. The pre-vaccination period was from January 1, 2008 to the date of vaccination, and the post-vaccination period, from 4 weeks after vaccination to December 31, 2009. The number of patients who required emergency transportation and outpatient consultation related to upper respiratory infections was recorded, and the numbers were compared between the pre- and post-vaccination periods.
Results: The emergency transportation rate was 0.023/year in the pre-vaccination period and 0.026/year in the post-vaccination period, but the difference was not significant (p = 0.80). The outpatient consultation rate was lower in the post-vaccination period than in the pre-vaccination period (0.49/year and 0.32/year, respectively), but again, the difference was not statistically significant (p = 0.059).
Conclusion: Pneumonia pneumococcal vaccination achieved no significant change in the emergency transportation rate or in the outpatient consultation rate of patients over 70 years of age living on islands. As our study has several limitations in its methods, further investigation of the effects of pneumococcal vaccination is needed.