Nearly eight years ago, we formed the Typhoid Vaccine Acceleration Consortium (TyVAC). At that time, typhoid vaccine uptake in endemic countries was low and we didn’t have a prequalified typhoid conjugate vaccine (TCV) or a World Health Organization (WHO) recommendation for TCV. In October 2017, the Strategic Group of Experts on Immunization met and reviewed data for a new TCV. From there, the field of typhoid prevention and control raced ahead. By November 2017, Gavi, the Vaccine Alliance, (Gavi) opened a funding window to support TCV and in December 2017, WHO prequalified Typbar TCV®, the first TCV to receive such designation. In March 2018, WHO released an updated position paper to recommend TCV for countries with endemic typhoid and/or a high burden of drug-resistant typhoid.
Progress at a rapid pace
Since then, we have witnessed monumental progress in getting TCV to the children who need it most. Liberia, Malawi, Nepal, Pakistan, and Zimbabwe have introduced TCV with support from Gavi, reaching more than 64 million children through campaign introductions. Three more countries—Fiji, Samoa, Tuvalu—have introduced TCV with partner support. Five additional countries, including the first Francophone African country, are expected to introduce TCV with Gavi support in the coming year. Additionally, we now have four WHO prequalified TCV products; two are available with support from Gavi.
We have an incredible amount of essential data about TCV, including efficacy studies from Bangladesh, Malawi, and Nepal, and we’ve continued work to improve our understanding about—and the evidence on—longer-term TCV efficacy, immunogenicity, waning, and impact. We also now know that TCVs are safe and effective in HIV-exposed, uninfected children, and have a better understanding of how costly typhoid illness is for families.
Our work is far from complete
As a typhoid community, we have made great progress in typhoid prevention and control since TyVAC’s inception. However, our work is not over. The urgency for typhoid prevention and control has increased. We are seeing increasing rates of drug-resistant typhoid, a worrying trend that threatens progress against typhoid and increases the risk to children worldwide. Typhoid intestinal perforation, a serious and life-threatening consequence of untreated typhoid that requires surgery to remedy, is now recognized as an important indicator of typhoid burden in countries lacking blood culture surveillance data.
As extreme weather events are heightened due to climate change, typhoid endemic countries will continue to face floods, droughts, and more frequent, longer, and intense heat waves, exacerbating the risk of typhoid. And basic water and sanitation infrastructure continues to elude millions of people globally, exponentially raising the risk of illness and disease transmission.
Taking on typhoid in 2025
In our interconnected world—where global health risks to one country can impact a region or even the world—the need to control typhoid and protect as many children as possible is as strong as ever. As I reflect on this year, I am bolstered by the great strides in the typhoid field. Yet challenges remain. TyVAC will continue our work forward in 2025, engaging stakeholders and partners in the typhoid community, generating additional data on the impact and effectiveness of TCV, supporting governments to make strategic TCV decisions for their countries; and continuing to raise awareness about the urgency of typhoid on global and regional agendas. Wishing all of our readers a happy and healthy New Year.
Photo: Dr. Laurens with Golden, the first participant in the TCV efficacy study in Malawi, 2018. Credit: TyVAC
