As we have seen over the last few years, our gut microbes (also called gut microbiota or microbiome) impact our health in multitudinous ways, from gut health to brain health, immune health to heart health, and everything in between. Recently, researchers conducted two studies that identified a link between gut microbiota composition and response to vaccination. The studies were a collaborative effort between the University of Maryland School of Medicine and the Center for Vaccine Development, and were published in the Public Library of Sciences ONE journal.

The first study determined the impact of oral typhoid vaccination on the microbiota in the human gut,1 and the second study assessed the impact of vaccines against the pathogen Shigella on the gut microbiota in a primate experimental model.2 Both studies found that the higher diversity of the gut microbes, the greater the protection of the vaccine. This is important information that may one day help inform our public health policies, and perhaps change the way we deliver vaccines.

“Our research raises the intriguing possibility that the gut microbiota may play an important role in response to vaccines and susceptibility to enteric pathogens, or bacteria that affect the intestinal tract,” exclaimed lead researcher Claire Fraser, PhD. “This research provides a fascinating window into the human microbiome, and how the bacteria in our bodies impact our health. Both S. typhi and Shigella are still devastating to populations in certain parts of the world. We hope that this work might one day help to provide relief to those areas that still suffer from these diseases.”

Scientists at the Center for Vaccine Development have been working for many years to develop a better vaccine for typhoid, a condition that affects over 20 million people worldwide, mostly in south-central and south-east Asia. Perhaps looking to the gut will finally provide the answers. Wouldn’t it be great if we would use microbiome diversity as a criterion to be fixed before giving vaccines? I believe giving prebiotics, probiotics, fish oil, vitamin D, zinc, selenium, and an 80 percent plant-based diet will create microbiome diversity that, creates immune health and balance. This could help assure the vaccine would work and be less likely to harm the recipient. In fact, for those who have not received vaccines, the above nutrients and diet are likely to prevent or minimize the seriousness and duration of infections.

More studies are needed, and this research will likely lead to additional studies that will deepen our knowledge of that intricate relationship between “us” and “them.” We are truly a superorganism, or simply put a bus for our bacteria.

Albert Reece, MD, PhD, MBA, vice president for medical affairs at the University of Maryland stated “We expect more groundbreaking discoveries from these research scientists, paving the way for the treatment and prevention of deadly diseases throughout the world.” I look forward to what they might find and how it will help to solve the issues around potential vaccine injuries and vaccine failures.



  1. Eloe-Fadrosh EA, McArthur MA, Seekatz Am, et al., “Impact of oral typhoid vaccination on the human gut microbiota and correlations with S. typhi-specific immunological responses.” PLoS ONE, 2013; 8 (4): e62026
  2. Seekatz AM, Panda A, Rasko DA, et al., “Differential response of the Cygnomolgus macaque gut microbiota to Shigella infection.” PLoS ONE, 2013; 8 (6): e64212