Project timeline: 16/09/2019 - 15/02/2022
Dr. Subhra Chakraborty
Johns Hopkins University
Wellcome Trust
A rapid diagnostic test (RDT) that is simple, sensitive and specific would be highly valuable for the early confirmation of cholera outbreaks and for hotspot mapping in endemic settings. The current diagnostic tests for cholera, stool culture or RDTs are either requires ~72 hours in a good laboratory or the sensitivity and specificity are not optimal and varies.
We developed a novel RDT assay “Cholera-rapid LAMP based RDT (C-RLDT)” which is simple, rapid (<1hour), directly from stool, sensitive, specific, cold chain free, easy to interpret and inexpensive. This assay targets V. cholerae (ctxA and O1 rfb gene) using isothermal amplification. The limit of detection is similar to quantitative PCR. Our preliminary data with stool samples from endemic countries showed C-RLDT has high sensitivity and specificity compared to PCR and culture method. C-RLDT is capable of detecting cholera in water samples without enrichment.
We propose validating C-RLDT in comparison with culture, Crystal VC® and PCR and determining the operational performance and feasibility of implementing C-RLDT in District clinics as well as in a field setting when outbreaks occur in remote areas in Uganda, Nigeria and Bangladesh. We also propose to determine the validity of C-RLDT in detecting V. cholera from water.
We developed a simple and rapid diagnostic assay “C-RLDT” for the detection of cholera which could be applied to resource-poor settings. This assay is sensitive like PCR and specific and could detect cholera in stool and water. We aim to evaluate the performance and feasibility of the implementation of C-RLDT in Uganda, Nigeria and Bangladesh.
If this project is successful, C-RLDT could be integrated in the National cholera control plan in the cholera endemic countries.
David Sack, Johns Hopkins University as consultant
International Centre for Diarrhoeal Disease Research (icddr,b), Bangladesh
Nigeria Center for Disease Control (NCDC), Nigeria
National Health Laboratory & Diagnostic Services (NHLDS/CPHL), Ministry of Health, Uganda