EIP Special Studies

Streptococcus pneumoniae commonly causes pneumonia and sepsis. A pneumococcal conjugate vaccine covering 13 serotypes (strains) (PCV13) was licensed in 2010 with the recommendation to give to infants and children. This study sought to evaluate the effectiveness of the new vaccine against serotypes of Streptococcus pneumoniae that are included in the vaccine. Following the conclusion of this study, it was noted that rates of disease among adults older than 65 years of age declined by approximately 50%, demonstrating herd immunity afforded by the vaccine. In 2014, recommendations were amended to include providing PCV13 as well as the older pneumococcal polysaccharide vaccine (PPSV23) in adults older than 65 years of age. To evaluate the effectiveness of the PCV13 vaccine in adults older than 65 years of age, another study was begun in 2015.

The pneumococcal conjugate vaccine effectiveness studies investigated cases with severe pneumonia infections. However, there exists substantial burden to the population and healthcare system due to non-invasive pneumonia. Non-invasive, or non-bacteremic, pneumonia occurs when the bacteria is causing an infection in your lungs but has not gone so far as to enter the bloodstream. This study seeks to estimate the incidence of non-bacteremic pneumococcal pneumonia and the effectiveness of the 13-valent pneumococcal conjugate vaccine (PCV13) against such illness to further inform recommendations for PCV13 in adults.

Group B Streptococcus agalactiae (GBS) rarely causes meningitis and sepsis in newborn infants or neonates. Babies can be infected with this bacteria during the birthing process. Although protocols are currently in place to lessen transmission from the mother to the baby, illness can be further prevented through giving a vaccine to the mother during pregnancy. A vaccine would stimulate the mother's immune system to generate antibodies, which are proteins in your blood that fight infection. Antibodies can then be passed to the baby during pregnancy, thus protecting the baby from infection. This study seeks to estimate antibody levels associated with a meaningful reduction in disease to inform development of maternal vaccines to protect young infants against invasive GBS.

Note to laboratorians: Group B Streptococcus = Streptococcus agalactiae

Group A Streptococcus (GAS) can cause mild disease such as strep throat and very severe disease like necrotizing fasciitis (“flesh eating disease”) or streptococcal toxic shock syndrome. The purpose of this study is to identify genes that may help to explain why some people infected by GAS have mild disease and why some have very serious infections. This study may help improve treatment of GAS infections and prevent very severe disease in the future.