This is stimulating and thought provoking paper that addresses hitherto unknown intermediate host reservoirs which can do both endozoochorous and epizoochorous dispersal of Vibrio cholerae. The authors have furnished adequate circumstantial evidences that underpin the possible role of migratory waterfowls as disseminators of the pathogens. They have articulated the probable missing link in epidemic and pandemic cholera dissemination across continents, endorsed by the compelling evidences (Ref no: 26-30).

Their theoretical deducing results are convincing. Yet, I would like to indicate the possible antagonistic bacterial species (e.g. Enterococcus sp., Lactobacillus sp., Peptostreptococcus sp.) that are known to exert inhibitory substances in the guts, which in turn are known to destabilize the fate of V. cholerae (to an unknown proportion) within the intestinal system. This is very possible case and there are studies that document the above scenario and the presence of antagonistic bacterial species (against V. cholerae) thrive in guts of waterfowls (Damaré et al. 1979 - Appl Environ Microbiol. 38:258-266; Saikia et al. 1995 – Res. Vet. Sci. 58:288–289; Simonetta et al. 1997 – Lett. Appl. Microbiol. 24:139–143).

To summarize, it would be interesting to explore; a) what would be the trans-host fate of the pathogen through ecological food chain? b) what would be the microecological scenario of V. cholerae and its antagonists within the ‘intestinal ecosystem’ (as far as bacteria concerned) of migratory waterfowls? Such studies would give deeper insights into the continental ecology of cholera.

By

Natarajan Singaravelan