Health officials and local researchers have launched an emergency vaccination campaign to stem an outbreak of ceftriaxone-resistant typhoid in Hyderabad, Pakistan. The outbreak has sickened more than 800 people since it began in late 2016.

One-third of the world’s population is at risk of contracting typhoid.

This week immunization experts from around the world will gather in Geneva to review new evidence and discuss recommendations for WHO immunization policy. An important item on the agenda for the fall meeting is typhoid vaccines. A recommendation on the use of new typhoid conjugate vaccines (TCVs) could significantly impact the effort to reduce the global burden of typhoid, a disease that impacts nearly 12 million people a year.

In South Asia, where the burden of enteric fever is thought to be highest, most typhoid studies have focused on urban areas. As a result, researchers have been unsure how well available data could be extrapolated to predominantly rural areas.