Investigation on the correlation factors of positive Streptococcus pneumoniae antibody and IgG antibody level of Streptococcus pneumoniae in the elderly over 60 years old in Shenzhen.

Background: Pneumococcal Polysaccharide Vaccine (PPV-23), designed to protect against the most common serotype of Streptococcus pneumoniae, is intended to protect the elderly and other high-risk groups. However, the immunogenicity of all 23 pneumococcal polysaccharide vaccines in older adults has not been thoroughly studied.

Objective: The purpose of this study is to look into the factors that influence the effect of the pneumonia vaccine on the elderly over 60 years old in Shenzhen, as well as their IgG antibody level against Streptococcus pneumoniae.

Methods: To determine the immune effectiveness of pneumococcal vaccination in older adults over 60 years old, we used the 3rd generation enzyme-linked immunosorbent assay to detect the antibody level of older adults to all 23 pneumococcal polysaccharide vaccines following pneumococcal immunization.

Results: Vaccination, the number of physical examinations, pneumonia knowledge, and the pneumonia vaccination policy of the elderly in Shenzhen were all positively correlated with Streptococcus pneumoniae antibody positivity. The distribution of subtypes did not differ between elderly adults (over 65) and younger adults (under 65). The GMCs of IgG antibodies to PPS were significantly lower in males than in females for types 7f, 18c and 19a. At the same time, we found that people with chronic respiratory disease have lower type 9n than people without chronic respiratory disease. Other chronic diseases, such as hypertension and diabetes, had no difference in subtype distribution.

Conclusion: There was a statistically significant difference in antibody positivity rates for older people with more frequent medical check-ups in Shenzhen, indicating that publicity is playing a role. The effects of age, gender, and chronic diseases on naturally acquired anti-PPS IgG differ.