Can early antibiotic use make vaccination less effective?

10 May 2018
Can early antibiotic use make vaccination less effective?

New research led by the South Australian Health and Medical Research Institute (SAHMRI), European Molecular Biology Laboratory (EMBL) Australia and Flinders University has shown that in preclinical models, antibiotic exposure in infants impairs their responses to five important, routine vaccines that are administered daily around the world.

 The importance of vaccination

Vaccinations come second only to clean water as the most effective frontline strategies available for preventing infectious diseases. Vaccinations work by supporting the immune system in producing antibodies against diseases.

Antibody-mediated responses play a critical role in vaccine-mediated immunity. However, for reasons that are poorly understood, these responses vary significantly between individuals.

Published in Cell Host & Microbe today, research led by Associate Professor David Lynn, EMBL Australia Group Leader, Precision Medicine, SAHMRI and Associate Professor, College of Medicine and Public Health, Flinders University and his team has found that the use of antibiotics in early-life (in preclinical animal models) leads to impaired immune responses to five vaccinations routinely given to infants worldwide, including vaccines against meningitis, pneumonia, tuberculosis and whooping cough.

Associate Professor Lynn said that these findings are very important because by one year of age, 50 per cent of infants in Australia will be exposed to antibiotics, and this is the period of life that many of these vaccines are administered.

“We have showed that the bacteria in the gut (the microbiome) are important in shaping the strength of the infant immune system. It appears that antibiotics in the first year of life change the way the body builds immunity, and responds to vaccination,” Associate Professor Lynn said.

“Our findings could have significant implications for vaccination programs globally.”

Can a healthy microbiome be restored?

 Associate Professor Lynn said he’s hopeful it’s not all doom and gloom, and that we can strengthen and repair the healthy gut bugs by replacing them with transplants, prebiotics and probiotics. In mice, restoring a healthy gut microbiome after antibiotic exposure rescued the impaired vaccine responses.

The team has already established a clinical study at the Women’s and Children’s Hospital in Adelaide to identify whether this phenomenon also happens in human infants, and to explore how the healthy gut microbiome influences the effectiveness of vaccination.