Transmission of Vibrio cholerae Is Antagonized by Lytic Phage and Entry into the Aquatic Environment

2008

How Lytic Phage and Environmental Conditions Affect Cholera Transmission

Sample size: 6 publication 10 minutes Evidence: high

Author Information

Author(s): Nelson Eric J., Chowdhury Ashrafuzzaman, Flynn James, Schild Stefan, Bourassa Lori, Shao Yue, LaRocque Regina C., Calderwood Stephen B., Qadri Firdausi, Camilli Andrew

Primary Institution: Howard Hughes Medical Institute and the Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, Massachusetts, United States of America

Hypothesis

The study aims to determine the relevance of active but non-culturable (ABNC) cells and the impact of lytic phage on Vibrio cholerae transmission.

Conclusion

Culturable Vibrio cholerae, rather than ABNC cells, are the major contributors to infection, and lytic phage can block transmission.

Supporting Evidence

Vibrio cholerae loses the ability to culture upon transfer to pond water, entering the ABNC state.
Phage titer was too low to affect colonization immediately after shedding from patients.
After 24 hours in pond water, V. cholerae failed to colonize the small intestine.
Transcriptional analysis showed that bacteria quickly adjust to the stresses of the aquatic environment.
Phage had an undetectable influence on the adaptation of V. cholerae to nutrient-poor conditions.
ABNC cells and lytic phage together block transmission of cholera.

Takeaway

This study found that the bacteria that cause cholera can become less infectious when they enter a certain state in the environment, and viruses that attack these bacteria can make it even harder for them to spread.

Methodology

The study used a pond microcosm to observe the behavior of Vibrio cholerae and lytic phage over 24 hours, measuring culturability, infectious dose, and transcriptional changes.