Salmonella Typhi stool shedding by enteric fever patients and asymptomatic chronic carriers in an endemic urban setting


Farhana Khanam, Thomas C Darton, James E Meiring, Protup Kumer Sarker, Prasanta Kumar Biswas, Md Amirul Islam Bhuiyan, Nazmul Hasan Rajib, Susan Tonks, Andrew J Pollard, John D Clemens, Firdausi Qadri


The burden of Salmonella Typhi shedding in stool and its contribution to transmission in endemic settings is unknown. During passive surveillance S. Typhi shedding was seen during convalescence in 332 bacteremic typhoid patients although none persisted at one-year follow-up. Anti-Vi-IgG titres were measured in age-stratified cohort of serosurveillance participants. Systematic stool sampling of 303 participants with high anti-Vi-IgG titres identified one asymptomatic carrier shedding. These findings suggest ongoing S. Typhi transmission in this setting is more likely to occur from acute convalescent cases although better approaches are needed to identify true chronic carriers in the community to enable typhoid elimination.

Keywords: Typhoid fever; chronic carriers; stool shedding; transmission of S. Typhi.

Click here to read the article, published in The Journal of Infectious Diseases