New Vaccine May End Pneumonia

Each year, pneumonia kills millions of people worldwide. Vaccines have lowered death rates in the past 10 years: Together with access to antibiotics and improved nutrition, the vaccines have more than halved deaths in children — but pneumonia still kills more than 50,000 Americans every year, most of them senior citizens. However, a new vaccine may lower death rates drastically.

Vaccines introduced in the early 2000s target up to 23 of the deadliest forms of the bacterium that causes pneumonia, Streptococcus pneumoniae. The new vaccine, which is undergoing animal testing, may lower the number of deaths even further by targeting dozens of additional strains of S. pneumoniae. It may also anticipate future versions of the bacteria responsible for pneumococcal disease, which includes sepsis and meningitis.

The vaccine provoked an immune response to 72 forms of S. pneumoniae, including the 23 already included in existing pneumonia vaccines.

"We've made tremendous progress fighting the spread of pneumonia, especially among children. But if we're ever going to rid ourselves of the disease, we need to create smarter and more cost-effective vaccines," says the study's co-author Blaine Pfeifer, Ph.D., associate professor of chemical and biological engineering at the University at Buffalo's School of Engineering and Applied Sciences.

Each strain of S. pneumoniae contains unique polysaccharides, say researchers. Vaccines such as Prevnar 13 and Synflorix connect these sugars, sharing an electron, to a protein called CRM197. The process, known as a covalent bond, creates a potent vaccine that prompts the body to find and destroy bacteria before they colonize the body.

While effective, creating covalent bonds for each strain of S. pneumoniae is time-consuming and expensive. In addition, this type of immunization, known as a conjugate vaccine, prompts the body to eliminate each of the targeted bacteria types, regardless of whether the bacteria are idle or are attacking the body.

Another vaccine, Pneumovax 23, contains sugars of 23 of the most common types of S. pneumoniae. However, the immune response it provokes is not as strong as Prevnar because the sugars are not covalently linked.

"Traditional vaccines completely remove bacteria from the body. But we now know that bacteria — and in a larger sense, the microbiome — are beneficial to maintaining good health," says Charles H. Jones, the study's other co-lead author.

"That's really exciting is that we now have the ability — with the vaccine we're developing — to watch over bacteria and attack it only if it breaks away from the colony to cause an illness. That's important because if we leave the harmless bacteria in place, it prevents other harmful bacteria from filling that space."

The new vaccine is engineered in a way that makes it easy to add sugars (like Pneumovax) for a broad immune response to fight currently undiscovered strains of bacteria.

According to tests performed on mice and rabbits, the new vaccine stimulated an immune response to 72 of the more than 90 known strains of S. pneumoniae. In many cases, it outperformed Prevnar and Pneumovax.

According to Pfeifer, the vaccine has the potential to provide universal coverage against bacteria that cause pneumonia, meningitis, sepsis and other types of pneumococcal disease.

The research was published in the journal Science Advances.

New vaccines aren't the only discovery that may help reduce deaths from pneumonia. One of the leading causes of death among senior citizens living in long-term health facilities is acute respiratory illness (ARI), which includes pneumonia and bronchitis.

Research published in the Journal of the American Geriatrics Society found that patients who took higher doses of vitamin D (3,300-4,300 IU daily) experienced a 40 percent reduction in acute respiratory illness.