Scientists aim to elicit stronger immune response with higher dosage
Researchers plan to see if a higher dose of a pneumococcal vaccine will create a stronger immune response in older adults who received an earlier generation vaccine against pneumonia and other pneumococcal diseases.
The study supported by the National Institutes of Health will compare two dosages of a pneumococcal vaccine approved for children ages 6 weeks to 5 years, and adults 50 and older. The trial will enroll up to 882 men and women ages 55 to 74.
The study is funded by the National Institute of Allergy and Infectious Diseases (NIAID), part of NIH. Researchers hope to gain new insights into the immune responses needed to provide protection.
More than 300,000 people in the United States are hospitalized annually for pneumonia, according to the Centers for Disease Control and Prevention. In 2009, pneumonia ranked eighth among the 15 leading causes of death in the United States, with adults 55 and older accounting for the majority (92 percent) of all pneumonia-related deaths that year.
The bacterium Streptococcus pneumoniae can cause a type of pneumonia called pneumococcal pneumonia. S. pneumoniae can infect the upper respiratory tract and spread to the lungs, blood, middle ear or nervous system. Children younger than 5 and adults older than 65 are most susceptible to becoming ill from pneumococcal pneumonia. People who have been infected are susceptible to becoming re-infected.