Pneumococcal vaccination rates in Germany
At the school entrance examinations in 2020, the rates of complete pneumococcal vaccination among children between the ages of four and seven were 82.2% [2]. In contrast, an analysis of secondary data from the statutory health insurance (GKV) published in 2024 showed that the STIKO recommendations for adult high-risk patients in Germany are not being implemented to a sufficient extent. The 60 to 64 year old age group examined had a vaccination rate of 13 percent, while less than one in five people aged 16 and over with a chronic underlying disease had received the recommended indication vaccination [3].
Results of a US study
An American working group conducted a longitudinal study in New Haven (Connecticut, USA) to shed more light on the risk of pneumococcus transmission among older people. In two periods from 2020 to 2022, 121 people between the ages of 60 and 86 years old whose households (n=61) had no children were examined. Saliva samples were taken from the participants every 14 days over a period of ten weeks. They also filled out questionnaires on social behavior and health. The saliva samples were then examined for the presence of pneumococcal DNA using quantitative PCR (qPCR). Pneumococcal detection was positive in 52 of 1,088 saliva samples (4.8%). Around 22 percent of people tested positive on at least one day of sample collection. The researchers also recorded the extent to which the participants had contact with children and what age the children were.
Participants who had contact with children daily or every few days had a higher point prevalence of pneumococcal colonization than those who had no contact before sampling (10% vs. 1.6%). There were also differences between the children’s age groups. For example, the point prevalence for contact with babies (age < 12 months) was 14%, for toddlers (2 to 5 years) was 17% and for school children (> 10 years) was 8%.
The statistical analysis showed a threefold increased risk of infection with pneumococci when in contact with children under ten years of age (hazard ratio, HR, 3.0, 95% CI 1.3-7.2). In people who were with children every day or every few days, the risk was sixfold increased compared to older people without contact (HR 6.0, 2.3-15.2) [4].
According to the first author of the study, Dr. According to Anne Wyllie, Yale School of Public Health, New Haven, USA, the main benefit of pneumococcal vaccination for adults is to directly protect older adults who come into contact with children. Because they can still transmit pneumococci despite vaccination.
Limitations of the study
The authors point out that the study included predominantly white people (87%) with higher education. Therefore, the generalizability of the results to people from other ethnic groups, educational levels and regions is limited. In addition, the overall prevalence of carriers may have been underestimated because the samples were only from saliva and not from other areas of the upper respiratory tract.