Traditional pneumococcal vaccines can fight up to 23 of the most dangerous strains of pneumococcus, but a new vaccine may be able to fight all 90 strains.
Pneumococcus bacteria-the culprit behind pneumonia, meningitis, bronchitis and ear infections-causes nearly 15 million infections each year, and is a leading cause of death in children under 5.
Although vaccines targeting several pneumococcus strains have been available since the 1980s, researchers at the State University of New York at Buffalo have found a new way to train the bacteria that they believe will increase the number of strains vaccines can target without unnecessarily killing good bacteria.
The study, “Direct vaccination against pneumococcal disease,” was published in May 2016 in the Proceedings of the National Academy of Sciences (PNAS).
Blaine Pfeifer, associate professor in the department of chemical and biological engineering at the State University of New York at Buffalo, led the study and says, unlike traditional vaccines that prevent colonization, the new vaccine promotes it. The bacteria in the vaccine is programmed to attack only pneumococcus that are dangerous, leaving those that contribute to the body’s microbial balance.
He hopes the discovery will help improve the effectiveness of existing vaccines and reduce the reliance on antibiotics to treat pneumococcal disease.
Illnesses caused by pneumococcal bacteria are traditionally treated with antibiotics, but resistance to these front-line medications is a growing problem. According to the Centers for Disease Control and Prevention (CDC), 30% of the 34,000 cases of pneumococcal disease in 2013 were resistant to at least one or more types of antibiotics.
Vaccines are already available for some strains of pneumococcal disease, and have been effective in reducing the annual number of illness cases each year, according to the CDC. Those vaccines, however, cover just 13 or 23 strains of pneumococcus, and there are more than 90 strains that have been identified.
The new vaccine identifies its targets by reading proteins on the surface of the bacteria, killing only those whose proteins break off the bacteria and pose a threat to the host. The vaccine and has been shown in early studies to be 100% effective at the 12 most virulent strains of pneumococcus-and more, according to the study.
“The new active antigen that we’ve tested has the potential to enhance current vaccines by broadly protecting against the numerous bacterial serotypes that can cause pneumococcal disease,” Pfeifer told Medical Economics.
Another benefit of the vaccine, beyond its wider reach, is that it selectively destroys bacteria, killing only those that pose a threat and leaving bacteria that supports the body’s microbial balance.
“Our approach offers the potential to only target virulent forms of the pneumococcal bacteria that cause disease while leaving the non-virulent forms of the bacteria in-tact to spatially limit invasion by alternative pathogens,” Pfeifer said.
Although the effectiveness of the vaccine has primarily been tested through computer modeling and animals at this point, the research team hopes to move to human trials soon.