Researchers have developed a 3-in-1 vaccine against traveller’s diarrhoea effective against three common stomach bugs
A first-ever vaccine designed to give protection against three most common bugs that causes traveller’s diarrhoea worldwide have been developed by Canadian researchers from the University of Guelph.
Diarrhoea, a leading cause of illness in travellers is usually a short-lived and self-limiting condition and it affects about 20-50% of all travellers.
Travellers’ diarrhoea is most commonly caused by toxigenic Escherichia coli and enteroaggregative E. coli. Campylobacter infections are predominant in low and middle income countries of Northern Africa and Southeast Asia. Other common causative organisms include Salmonella, Shigella, Rotavirus and Norovirus ( both viruses causes outbreaks in cruise ships). Except for Giardiasis, parasitic infections are uncommon causes of travellers’ diarrhoea. Rotavirus is a leading cause of diarrhoea in under 5 children in India and Rotavirus vaccine was included as a part of the Universal Immunisation Programme (UIP) in 2016.
The so-called three-in-one conjugate vaccine combines together proteins from pathogenic E. coli with sugars from Shigella and Campylobacter jejuni
This novel three-in-one vaccine could save many lives in developing countries, where it’s estimated that these three common pathogens kill more than 100,000 children under age five each year.
This research by Prof. Mario Monteiro, a University of Guelph chemist and his team was published in the journal Vaccine.
The so-called three-in-one conjugate vaccine combines together proteins from pathogenic E. coli with sugars from Shigella and Campylobacter jejuni. The vaccine provided immunity against all three pathogens in animal tests with mice.
No licensed vaccines exist against any of these pathogens. A sugar-based vaccine developed by Monteiro in 2009 against campylobacter alone is currently undergoing human trials.
Prof. Monteiro said, this new three-in-one approach may ultimately overtake that earlier single-target vaccine, although any new vaccine may take decades to test and release. “We’re targeting three pathogens at the same time,” he added. “Instead of three shots, maybe you only need one.”
Monteiro said further research is needed to determine the optimum amounts of protein and sugars in the vaccine and to make the vaccine more efficient.