C. difficile vaccine proves safe, 100 percent effective in animal models

An experimental vaccine protected 100 percent of animal models against the highly infectious and virulent bacterium, Clostridium difficile, which causes an intestinal disease that kills approximately 30,000 Americans annually. The research is published ahead of print in Infection and Immunity.

In the study, the vaccine protected the mice and non-human primates against the purified toxins produced by C. difficile, as well as from an orogastric spore infection, a laboratory model that mimics the human disease, after only two immunizations.

"Animals that received two immunizations did not get sick or show signs of C. difficile-associated disease," says corresponding author Michele Kutzler, of Drexel University College of Medicine, Philadelphia.

"While our research was conducted in animal models, the results are very translatable to the clinic," says Kutzler. "In some cases, patients who acquire C. difficile can develop serious complications including severe diarrhea, toxic megacolon, bowel perforation, multi-organ failure, and death. Once fully developed, our DNA vaccine could prevent the deadly effects of C. difficile infection when administered to hospital patients at risk of acquiring C. difficile."

The protection following just two immunizations is especially important since the time window in humans between colonization with C. difficile and the onset of disease symptoms can be a mere 10-14 days, says Kutzler.

The vaccine protects against the bacterial toxins by mustering anti-toxin neutralizing antibodies, says Kutzler.

The cost of fighting the half million C. difficile infections that occur annually in the US is estimated to be nearly $10 billion, most of which could be saved by a successful preventive vaccine, says Kutzler. Morbidity and mortality have risen over the last decade, likely due to increased prevalence of relapsing disease, and hypervirulent strains, she adds.

Treating the disease is especially difficult, as the bacterial spores persist in the hospital environment, where most infections occur. There is no standard, effective treatment for recurrent disease, but a small number of experimental fecal transplants for C. difficile have had a very high success rate, with no adverse reactions.

"Since our was safe, effective after only two immunizations, and performed exceptionally well, we feel that this success warrants further studies using human patients," says Kutzler.

More information: Infection and Immunity. DOI: 10.1128/IAI.01950-14

add to favorites email to friend print save as pdf

Related Stories

Recommended for you

Liberia free of Ebola by Christmas, says president

4 hours ago

Liberia's president on Monday urged her countrymen to double their efforts to reach the government's goal of having zero new Ebola cases by Dec. 25, a target some experts have described as highly ambitious.

Madagascar working to contain plague outbreak

4 hours ago

Madagascar said Monday it is trying to contain an outbreak of plague—similar to the Black Death that swept Medieval Europe—that has killed 40 people and is spreading to the capital Antananarivo.

Developing a noninvasive test for endometriosis

4 hours ago

Researchers at UC San Francisco have identified patterns of genetic activity that can be used to diagnose endometriosis and its severity, a finding that may offer millions of women an alternative to surgery through a simple ...

User comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.