He laid the groundwork for life-saving cholera vaccines
By uncovering how the cholera bacterium causes disease and how immunity develops, Jan Holmgren laid the groundwork for vaccines that save tens of thousands of lives every year. He is now awarded one of the world’s most prestigious prizes in global health.
Senior Professor Jan Holmgren at the Sahlgrenska Academy, University of Gothenburg, is awarded the 2026 John Dirks Canada Gairdner Global Health Award together with epidemiologist John Clemens. The award recognizes research that has had a major impact on global health.
From basic research to vaccine
Through his research, Jan Holmgren showed how the bacterium Vibrio cholerae causes disease. He described the structure and function of the cholera toxin, which drives the severe fluid loss. He also demonstrated how immunity develops in the intestine and can be induced by oral vaccination. This knowledge proved critical for stopping the infection.
![[none]](/sites/default/files/styles/50_10_6_xmedium_1x/public/2026-04/Jan%20Holmgren%2005%20bred.jpg?h=ff525877&itok=Iqsd5x1m)
Building on these discoveries, Jan Holmgren developed the first effective oral cholera vaccine. The vaccine is based on inactivated bacteria and a nontoxic part of the toxin and provides robust protection in the intestine, where the infection occurs.
“What is most gratifying about this award is that the vaccines we have developed are now being used and are saving tens of thousands of lives every year,” says Jan Holmgren.
Vaccines that reach those in need
Together with John Clemens, who led large field trials in cholera-affected communities, their work showed that the vaccines are safe and provide long-lasting protection. They also reduce transmission throughout communities.
Through international collaborations, the vaccines have been produced at low cost. Today, they are used both in outbreak response and for preventive use in areas where cholera is endemic.
“This work has evolved over a long period and in close collaboration with many highly skilled colleagues. Beyond the close collaboration with John Clemens, I would especially like to highlight Ann-Mari Svennerholm, whose contributions were crucial in the early research and in the development of the vaccine,” says Jan Holmgren.
The research has long been recognized internationally and has received numerous awards. In 2019, Jan Holmgren and John Clemens received the prestigious Prince Mahidol Award in global health. They are now also receiving the 2026 John Dirks Canada Gairdner Global Health Award.
Cholera is caused by Vibrio cholerae and spreads through contaminated water. It remains common in low-income settings with poor sanitation, especially in parts of Africa and Asia. Outbreaks often follow crises such as conflict and natural disasters. If untreated, it can rapidly cause severe diarrhea and life-threatening dehydration and can be fatal within hours.
