A new clinical trial by researchers from Cincinnati Children's reports encouraging progress toward a long-sought vaccine against Shigella, a leading cause of diarrheal disease worldwide. Every year, Shigella infects tens of millions of people worldwide and causes hundreds of thousands of deaths. In the US, an estimated 450,000 Shigella infections occur annually, with over 5,000 people hospitalized and dozens dying. The highly contagious Shigella spreads through fecal contamination of water or food, as well as through person-to-person contact, and is increasingly difficult to treat due to growing antibiotic resistance. No licensed Shigella vaccine exists. Published in the Lancet Infectious Diseases, a new study evaluated an oral vaccine candidate called WRSs2. The vaccine was designed to protect against Shigella sonnei. Two doses of WRSs2 provided 89% protection against Shigella sonnei compared with placebo. The findings of the new study support advancing WRSs2 into larger clinical trials. In this trial, researchers evaluated the safety and efficacy of the agent in a controlled human infection model. The WRS2 vaccine uses a live but attenuated form of the bacterium to stimulate immune protection without causing full disease. In addition to reducing illness, vaccinated participants experienced less severe symptoms and lower levels of bacterial shedding, suggesting the vaccine may also help curb transmission. @ https://www.prnewswire.com/news-releases/clinical-trial-of-shigella-vaccine-shows-89-protection-302816022.html
